Psoriasis

Friday, Feb. 10, 2023, marked the first time a patient told me they had used ChatGPT to answer a medical question. I’ve been reluctant to write about this super-buzzy new AI chatbot, but I am starting to think it is the real deal. Just how powerful is it? Well, ChatGPT might in fact be writing this column right now. It isn’t. No really, it’s me. But if not for the few cues (“super-buzzy”) that you’ll recognize as my writing voice, there might not be any way for you to know if I wrote this or not.

It’s perfectly OK if you’ve no clue what I’m talking about. ChatGPT is an AI chatbot that burst into public view just a couple months ago. Not your parent’s chatbot, this one is capable of answering questions in conversational language. It is jaw-droppingly good. Like Google, you can type in a question and it offers you answers. Rather than giving you a list of websites and a few Wikipedia blurbs, however, ChatGPT answers your question in human-like text. It can also create content on demand. For example, I asked it to write a Valentine poem to a dermatologist, and it gave me five stanzas starting with:

Oh gentle healer of skin so fair,
Your touch is soft and hands so rare,
With your skills and gentle care,
You make my heart skip with a flare.

Not good enough to send to my wife. But not bad.

If you ask it again, it will create a whole new one for you. Amusing, yes? What if you asked ChatGPT to explain psoriasis, or any medical condition for that matter, to a patient? The replies are quite good. Some even better than what I’m currently using for my patients. It can also offer treatment recommendations, vacation advice, and plan, with recipes, a dinner party for six with one vegan and one gluten-free couple. If you are a programmer, it can write code. Ask it for a Wordpress plugin to add to your website and your eyes will widen as you see it magically appear before you. What if you find that you just don’t like your daughter’s new boyfriend? Yep, it will write the text or email for you to help with this discussion. I’ve saved that one.

I tried “What are treatments for bullous pemphigoid that has been refractory to topical steroid, oral prednisone, and oral tetracyclines?” It replied with five ideas, including the standard methotrexate and azathioprine but also IVIG, Rituxan, even other biologics. Write an op note? Appeal a denied prior authorization to a payer? Write a clinic note for a complete skin exam? Check, check, check. Are you starting to think it might be the real deal, too?

Before we sell the farm though, there are significant limitations. Despite how swotty ChatGPT seems, it is not smart. That is, “it” has no idea what “it” is saying. ChatGPT is an incredibly sophisticated algorithm that has learned the probability of what word comes next in a conversation. To do so, it read the Internet. Billions (trillions?) of words make it possible to predict what is the best answer to any question. But – it’s only as good as the Internet, so there’s that. My patient who used ChatGPT has dissecting cellulitis and asked what to do for scarring alopecia. Some of the answers were reasonable, but some, such as transplanting hairs into the scarred areas, would not likely be helpful. That is unless ChatGPT knows something I don’t.

Having wasted hours of time playing with this thing rather than writing my column, I asked ChatGPT to write an article about itself in the style of Christopher Hitchens. It was nothing like his incisive and eloquent prose, but it wrote 500 words in a few seconds ending with:

“The reality is that there is no substitute for human interaction and empathy in the field of dermatology. Dermatologists must be cautious in their adoption of ChatGPT and ensure that they are not sacrificing the quality of patient care in the pursuit of efficiency and convenience.”

I’m not sure I could have said it better myself.

Dr. Benabio is director of Healthcare Transformation and chief of dermatology at Kaiser Permanente San Diego. The opinions expressed in this column are his own and do not represent those of Kaiser Permanente. Dr. Benabio is @Dermdoc on Twitter. Write to him at [email protected].

Friday, Feb. 10, 2023, marked the first time a patient told me they had used ChatGPT to answer a medical question. I’ve been reluctant to write about this super-buzzy new AI chatbot, but I am starting to think it is the real deal. Just how powerful is it? Well, ChatGPT might in fact be writing this column right now. It isn’t. No really, it’s me. But if not for the few cues (“super-buzzy”) that you’ll recognize as my writing voice, there might not be any way for you to know if I wrote this or not.

It’s perfectly OK if you’ve no clue what I’m talking about. ChatGPT is an AI chatbot that burst into public view just a couple months ago. Not your parent’s chatbot, this one is capable of answering questions in conversational language. It is jaw-droppingly good. Like Google, you can type in a question and it offers you answers. Rather than giving you a list of websites and a few Wikipedia blurbs, however, ChatGPT answers your question in human-like text. It can also create content on demand. For example, I asked it to write a Valentine poem to a dermatologist, and it gave me five stanzas starting with:

Oh gentle healer of skin so fair,
Your touch is soft and hands so rare,
With your skills and gentle care,
You make my heart skip with a flare.

Not good enough to send to my wife. But not bad.

If you ask it again, it will create a whole new one for you. Amusing, yes? What if you asked ChatGPT to explain psoriasis, or any medical condition for that matter, to a patient? The replies are quite good. Some even better than what I’m currently using for my patients. It can also offer treatment recommendations, vacation advice, and plan, with recipes, a dinner party for six with one vegan and one gluten-free couple. If you are a programmer, it can write code. Ask it for a Wordpress plugin to add to your website and your eyes will widen as you see it magically appear before you. What if you find that you just don’t like your daughter’s new boyfriend? Yep, it will write the text or email for you to help with this discussion. I’ve saved that one.

I tried “What are treatments for bullous pemphigoid that has been refractory to topical steroid, oral prednisone, and oral tetracyclines?” It replied with five ideas, including the standard methotrexate and azathioprine but also IVIG, Rituxan, even other biologics. Write an op note? Appeal a denied prior authorization to a payer? Write a clinic note for a complete skin exam? Check, check, check. Are you starting to think it might be the real deal, too?

Before we sell the farm though, there are significant limitations. Despite how swotty ChatGPT seems, it is not smart. That is, “it” has no idea what “it” is saying. ChatGPT is an incredibly sophisticated algorithm that has learned the probability of what word comes next in a conversation. To do so, it read the Internet. Billions (trillions?) of words make it possible to predict what is the best answer to any question. But – it’s only as good as the Internet, so there’s that. My patient who used ChatGPT has dissecting cellulitis and asked what to do for scarring alopecia. Some of the answers were reasonable, but some, such as transplanting hairs into the scarred areas, would not likely be helpful. That is unless ChatGPT knows something I don’t.

Having wasted hours of time playing with this thing rather than writing my column, I asked ChatGPT to write an article about itself in the style of Christopher Hitchens. It was nothing like his incisive and eloquent prose, but it wrote 500 words in a few seconds ending with:

“The reality is that there is no substitute for human interaction and empathy in the field of dermatology. Dermatologists must be cautious in their adoption of ChatGPT and ensure that they are not sacrificing the quality of patient care in the pursuit of efficiency and convenience.”

I’m not sure I could have said it better myself.

Dr. Benabio is director of Healthcare Transformation and chief of dermatology at Kaiser Permanente San Diego. The opinions expressed in this column are his own and do not represent those of Kaiser Permanente. Dr. Benabio is @Dermdoc on Twitter. Write to him at [email protected].

Friday, Feb. 10, 2023, marked the first time a patient told me they had used ChatGPT to answer a medical question. I’ve been reluctant to write about this super-buzzy new AI chatbot, but I am starting to think it is the real deal. Just how powerful is it? Well, ChatGPT might in fact be writing this column right now. It isn’t. No really, it’s me. But if not for the few cues (“super-buzzy”) that you’ll recognize as my writing voice, there might not be any way for you to know if I wrote this or not.

It’s perfectly OK if you’ve no clue what I’m talking about. ChatGPT is an AI chatbot that burst into public view just a couple months ago. Not your parent’s chatbot, this one is capable of answering questions in conversational language. It is jaw-droppingly good. Like Google, you can type in a question and it offers you answers. Rather than giving you a list of websites and a few Wikipedia blurbs, however, ChatGPT answers your question in human-like text. It can also create content on demand. For example, I asked it to write a Valentine poem to a dermatologist, and it gave me five stanzas starting with:

Oh gentle healer of skin so fair,
Your touch is soft and hands so rare,
With your skills and gentle care,
You make my heart skip with a flare.

Not good enough to send to my wife. But not bad.

If you ask it again, it will create a whole new one for you. Amusing, yes? What if you asked ChatGPT to explain psoriasis, or any medical condition for that matter, to a patient? The replies are quite good. Some even better than what I’m currently using for my patients. It can also offer treatment recommendations, vacation advice, and plan, with recipes, a dinner party for six with one vegan and one gluten-free couple. If you are a programmer, it can write code. Ask it for a Wordpress plugin to add to your website and your eyes will widen as you see it magically appear before you. What if you find that you just don’t like your daughter’s new boyfriend? Yep, it will write the text or email for you to help with this discussion. I’ve saved that one.

I tried “What are treatments for bullous pemphigoid that has been refractory to topical steroid, oral prednisone, and oral tetracyclines?” It replied with five ideas, including the standard methotrexate and azathioprine but also IVIG, Rituxan, even other biologics. Write an op note? Appeal a denied prior authorization to a payer? Write a clinic note for a complete skin exam? Check, check, check. Are you starting to think it might be the real deal, too?

Before we sell the farm though, there are significant limitations. Despite how swotty ChatGPT seems, it is not smart. That is, “it” has no idea what “it” is saying. ChatGPT is an incredibly sophisticated algorithm that has learned the probability of what word comes next in a conversation. To do so, it read the Internet. Billions (trillions?) of words make it possible to predict what is the best answer to any question. But – it’s only as good as the Internet, so there’s that. My patient who used ChatGPT has dissecting cellulitis and asked what to do for scarring alopecia. Some of the answers were reasonable, but some, such as transplanting hairs into the scarred areas, would not likely be helpful. That is unless ChatGPT knows something I don’t.

Having wasted hours of time playing with this thing rather than writing my column, I asked ChatGPT to write an article about itself in the style of Christopher Hitchens. It was nothing like his incisive and eloquent prose, but it wrote 500 words in a few seconds ending with:

“The reality is that there is no substitute for human interaction and empathy in the field of dermatology. Dermatologists must be cautious in their adoption of ChatGPT and ensure that they are not sacrificing the quality of patient care in the pursuit of efficiency and convenience.”

I’m not sure I could have said it better myself.

Dr. Benabio is director of Healthcare Transformation and chief of dermatology at Kaiser Permanente San Diego. The opinions expressed in this column are his own and do not represent those of Kaiser Permanente. Dr. Benabio is @Dermdoc on Twitter. Write to him at [email protected].

Both public and private health plans score poorly when it comes to providing access to autoimmune medication, according to a report commissioned by the Autoimmune Association and Let My Doctors Decide, a national partnership of health care professionals. The analysis, published Jan. 26, found that 75% of insurers in the United States have policies that can limit coverage for Food and Drug Administration–approved medications for Crohn’s disease, lupus nephritis, multiple sclerosis, psoriasis, psoriatic arthritis, rheumatoid arthritis, and ulcerative colitis.

“Choice among health plans is a hallmark of the American health insurance system, yet this analysis shows that people living with autoimmune conditions have few, if any, coverage choices that do not involve significant to severe access restrictions,” the authors wrote.

The study looked at three common utilization management policies by health plans that can limit coverage of certain medications: step therapy, formulary/tier placement, and prior authorization. To compare health plans, researchers weighted these policies using a point system. Each medication indicated for each condition was given a score of 0-4 based on access restrictions in a health plan. If a plan used step therapy, it received one point, and requiring prior authorization added an additional point. They also added points based on where a drug appeared on a plan’s formulary. A lower total score meant fewer access barriers. The numbers were then added, and each health plan received a grade of A, B, C, or F based on their average score. The datasets and analysis were provided and performed by the data analytics firm MMIT.

Nearly 9 in 10 Medicare plans received a C or worse for coverage of medication received via mail order or the pharmacy. In commercial plans, the majority of plans scored Cs or Fs for six of the seven conditions, excluding lupus nephritis, where 67% of all commercial health plans scored a B for access to these medications.

Physician-administered medications tended to receive poorer coverage than drugs received via pharmacy. Across all conditions, 65% of Medicare Advantage plans scored an F for physician-administered medication access. For both psoriasis and multiple sclerosis, at least 80% of Medicare plans earned failing scores because of these restrictions. Coverage was poorer on both commercial and health exchange plans, where across all conditions, 83% achieved failing scores. Two exceptions were the Southern and Northern California PPO plans by the Kaiser Foundation Health Plan. Out of the largest 25 health plans in the United States, these two plans earned As in coverage for physician-administered medications across all seven autoimmune conditions.

The report shows “a growing disconnect between science and health insurance benefit designs that were developed in the 1960s and 1970s,” Kenneth Thorpe, PhD, of Emory University, Atlanta, said in an interview. Insurers originally designed these benefits to prevent excessive utilization in a population of mostly acutely ill patients, he said, whereas now, 90% of healthcare spending is linked to chronic conditions. For these patients, research shows that incentivizing patients to adhere to medications results in fewer hospitalizations and, therefore, more cost savings, Thorpe noted. These plans also do not consider that there is no average patient, he said, and healthcare providers should be able to match each patient to the best treatment option for them rather than trying out other less expensive medications first. “To the extent that physicians can have the flexibility to provide medications and treatments to patients that are going to have the best clinical response, that’s better outcomes at lower cost,” Dr. Thorpe said. While research shows heterogeneity in patient outcomes with different medication, “benefit designs from the past just don’t recognize that.”

Neither America’s Health Insurance Plans nor Pharmaceutical Care Management Association responded to a request for comment.

Quardricos Driskell, executive director of Let My Doctors Decide and vice president of government relations and public policy at the Autoimmune Association, hopes the study will spur action by policy makers and health plans to improve access to medications for the people who need them. Another larger point of the report is to “uphold the sanctity of protecting the doctor and patient relationship,” he said in an interview, adding “that decisions fundamentally need to be made not by insurance plans or middleman pharmacy benefit managers, but by the provider and patient.”

Mr. Driskell and Dr. Thorpe reported no relevant financial relationships. 

A version of this article first appeared on Medscape.com.

Both public and private health plans score poorly when it comes to providing access to autoimmune medication, according to a report commissioned by the Autoimmune Association and Let My Doctors Decide, a national partnership of health care professionals. The analysis, published Jan. 26, found that 75% of insurers in the United States have policies that can limit coverage for Food and Drug Administration–approved medications for Crohn’s disease, lupus nephritis, multiple sclerosis, psoriasis, psoriatic arthritis, rheumatoid arthritis, and ulcerative colitis.

“Choice among health plans is a hallmark of the American health insurance system, yet this analysis shows that people living with autoimmune conditions have few, if any, coverage choices that do not involve significant to severe access restrictions,” the authors wrote.

The study looked at three common utilization management policies by health plans that can limit coverage of certain medications: step therapy, formulary/tier placement, and prior authorization. To compare health plans, researchers weighted these policies using a point system. Each medication indicated for each condition was given a score of 0-4 based on access restrictions in a health plan. If a plan used step therapy, it received one point, and requiring prior authorization added an additional point. They also added points based on where a drug appeared on a plan’s formulary. A lower total score meant fewer access barriers. The numbers were then added, and each health plan received a grade of A, B, C, or F based on their average score. The datasets and analysis were provided and performed by the data analytics firm MMIT.

Nearly 9 in 10 Medicare plans received a C or worse for coverage of medication received via mail order or the pharmacy. In commercial plans, the majority of plans scored Cs or Fs for six of the seven conditions, excluding lupus nephritis, where 67% of all commercial health plans scored a B for access to these medications.

Physician-administered medications tended to receive poorer coverage than drugs received via pharmacy. Across all conditions, 65% of Medicare Advantage plans scored an F for physician-administered medication access. For both psoriasis and multiple sclerosis, at least 80% of Medicare plans earned failing scores because of these restrictions. Coverage was poorer on both commercial and health exchange plans, where across all conditions, 83% achieved failing scores. Two exceptions were the Southern and Northern California PPO plans by the Kaiser Foundation Health Plan. Out of the largest 25 health plans in the United States, these two plans earned As in coverage for physician-administered medications across all seven autoimmune conditions.

The report shows “a growing disconnect between science and health insurance benefit designs that were developed in the 1960s and 1970s,” Kenneth Thorpe, PhD, of Emory University, Atlanta, said in an interview. Insurers originally designed these benefits to prevent excessive utilization in a population of mostly acutely ill patients, he said, whereas now, 90% of healthcare spending is linked to chronic conditions. For these patients, research shows that incentivizing patients to adhere to medications results in fewer hospitalizations and, therefore, more cost savings, Thorpe noted. These plans also do not consider that there is no average patient, he said, and healthcare providers should be able to match each patient to the best treatment option for them rather than trying out other less expensive medications first. “To the extent that physicians can have the flexibility to provide medications and treatments to patients that are going to have the best clinical response, that’s better outcomes at lower cost,” Dr. Thorpe said. While research shows heterogeneity in patient outcomes with different medication, “benefit designs from the past just don’t recognize that.”

Neither America’s Health Insurance Plans nor Pharmaceutical Care Management Association responded to a request for comment.

Quardricos Driskell, executive director of Let My Doctors Decide and vice president of government relations and public policy at the Autoimmune Association, hopes the study will spur action by policy makers and health plans to improve access to medications for the people who need them. Another larger point of the report is to “uphold the sanctity of protecting the doctor and patient relationship,” he said in an interview, adding “that decisions fundamentally need to be made not by insurance plans or middleman pharmacy benefit managers, but by the provider and patient.”

Mr. Driskell and Dr. Thorpe reported no relevant financial relationships. 

A version of this article first appeared on Medscape.com.

Both public and private health plans score poorly when it comes to providing access to autoimmune medication, according to a report commissioned by the Autoimmune Association and Let My Doctors Decide, a national partnership of health care professionals. The analysis, published Jan. 26, found that 75% of insurers in the United States have policies that can limit coverage for Food and Drug Administration–approved medications for Crohn’s disease, lupus nephritis, multiple sclerosis, psoriasis, psoriatic arthritis, rheumatoid arthritis, and ulcerative colitis.

“Choice among health plans is a hallmark of the American health insurance system, yet this analysis shows that people living with autoimmune conditions have few, if any, coverage choices that do not involve significant to severe access restrictions,” the authors wrote.

The study looked at three common utilization management policies by health plans that can limit coverage of certain medications: step therapy, formulary/tier placement, and prior authorization. To compare health plans, researchers weighted these policies using a point system. Each medication indicated for each condition was given a score of 0-4 based on access restrictions in a health plan. If a plan used step therapy, it received one point, and requiring prior authorization added an additional point. They also added points based on where a drug appeared on a plan’s formulary. A lower total score meant fewer access barriers. The numbers were then added, and each health plan received a grade of A, B, C, or F based on their average score. The datasets and analysis were provided and performed by the data analytics firm MMIT.

Nearly 9 in 10 Medicare plans received a C or worse for coverage of medication received via mail order or the pharmacy. In commercial plans, the majority of plans scored Cs or Fs for six of the seven conditions, excluding lupus nephritis, where 67% of all commercial health plans scored a B for access to these medications.

Physician-administered medications tended to receive poorer coverage than drugs received via pharmacy. Across all conditions, 65% of Medicare Advantage plans scored an F for physician-administered medication access. For both psoriasis and multiple sclerosis, at least 80% of Medicare plans earned failing scores because of these restrictions. Coverage was poorer on both commercial and health exchange plans, where across all conditions, 83% achieved failing scores. Two exceptions were the Southern and Northern California PPO plans by the Kaiser Foundation Health Plan. Out of the largest 25 health plans in the United States, these two plans earned As in coverage for physician-administered medications across all seven autoimmune conditions.

The report shows “a growing disconnect between science and health insurance benefit designs that were developed in the 1960s and 1970s,” Kenneth Thorpe, PhD, of Emory University, Atlanta, said in an interview. Insurers originally designed these benefits to prevent excessive utilization in a population of mostly acutely ill patients, he said, whereas now, 90% of healthcare spending is linked to chronic conditions. For these patients, research shows that incentivizing patients to adhere to medications results in fewer hospitalizations and, therefore, more cost savings, Thorpe noted. These plans also do not consider that there is no average patient, he said, and healthcare providers should be able to match each patient to the best treatment option for them rather than trying out other less expensive medications first. “To the extent that physicians can have the flexibility to provide medications and treatments to patients that are going to have the best clinical response, that’s better outcomes at lower cost,” Dr. Thorpe said. While research shows heterogeneity in patient outcomes with different medication, “benefit designs from the past just don’t recognize that.”

Neither America’s Health Insurance Plans nor Pharmaceutical Care Management Association responded to a request for comment.

Quardricos Driskell, executive director of Let My Doctors Decide and vice president of government relations and public policy at the Autoimmune Association, hopes the study will spur action by policy makers and health plans to improve access to medications for the people who need them. Another larger point of the report is to “uphold the sanctity of protecting the doctor and patient relationship,” he said in an interview, adding “that decisions fundamentally need to be made not by insurance plans or middleman pharmacy benefit managers, but by the provider and patient.”

Mr. Driskell and Dr. Thorpe reported no relevant financial relationships. 

A version of this article first appeared on Medscape.com.

The first biosimilar for Humira, adalimumab-atto (Amjevita), is now available in the United States, according to an announcement on Jan. 31 by the manufacturer, Amgen. At least seven other U.S. Food and Drug Administration–approved Humira biosimilars are expected to become available later in 2023.

Amjevita was approved by the FDA in September 2016 for multiple inflammatory diseases, including rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn’s disease, ulcerative colitis, and plaque psoriasis. The delayed launch was part of a global settlement with Humira’s manufacturer, AbbVie.

Humira (adalimumab) has been available since 2002 and is consistently one of the top-selling drugs in the United States. A single 40-mg Amjevita pen device will be available at two prices: a list price (wholesale acquisition cost) of $1,557.59, 55% below the current Humira list price, and a list price of $3,288.24, 5% below the current Humira list price, according to Amgen.

“Amgen’s goal is to provide broad access for patients by offering two options to health plans and pharmacy benefit managers,” the company said in the press release.

Patients are less likely to benefit from the more significant discount, said Marta Wosinska, PhD, a health care economist at the Brookings Institute in Washington, DC. It's expected that insurance companies will use the higher list price for Amjevita, she said, as this higher price will also likely have higher rebates. Rebates are payments to health insurance payers provided by drug manufacturers to promote use of an expensive drug. Some pharmacy benefit managers have already said that they plan to charge patients the same amount for Humira as its biosimilars, Dr. Wosinska said.

"For an existing patient, there's really no incentive for them to switch," she said in an interview.

So far only one insurance company, Kaiser Permanente, has plans to switch patients over to biosimilars, according to the health policy podcast Tradeoffs, and the insurer will stop covering Humira by the end of this year.

A version of this article first appeared on Medscape.com.

*This story was updated 2/1/2023.

The first biosimilar for Humira, adalimumab-atto (Amjevita), is now available in the United States, according to an announcement on Jan. 31 by the manufacturer, Amgen. At least seven other U.S. Food and Drug Administration–approved Humira biosimilars are expected to become available later in 2023.

Amjevita was approved by the FDA in September 2016 for multiple inflammatory diseases, including rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn’s disease, ulcerative colitis, and plaque psoriasis. The delayed launch was part of a global settlement with Humira’s manufacturer, AbbVie.

Humira (adalimumab) has been available since 2002 and is consistently one of the top-selling drugs in the United States. A single 40-mg Amjevita pen device will be available at two prices: a list price (wholesale acquisition cost) of $1,557.59, 55% below the current Humira list price, and a list price of $3,288.24, 5% below the current Humira list price, according to Amgen.

“Amgen’s goal is to provide broad access for patients by offering two options to health plans and pharmacy benefit managers,” the company said in the press release.

Patients are less likely to benefit from the more significant discount, said Marta Wosinska, PhD, a health care economist at the Brookings Institute in Washington, DC. It's expected that insurance companies will use the higher list price for Amjevita, she said, as this higher price will also likely have higher rebates. Rebates are payments to health insurance payers provided by drug manufacturers to promote use of an expensive drug. Some pharmacy benefit managers have already said that they plan to charge patients the same amount for Humira as its biosimilars, Dr. Wosinska said.

"For an existing patient, there's really no incentive for them to switch," she said in an interview.

So far only one insurance company, Kaiser Permanente, has plans to switch patients over to biosimilars, according to the health policy podcast Tradeoffs, and the insurer will stop covering Humira by the end of this year.

A version of this article first appeared on Medscape.com.

*This story was updated 2/1/2023.

The first biosimilar for Humira, adalimumab-atto (Amjevita), is now available in the United States, according to an announcement on Jan. 31 by the manufacturer, Amgen. At least seven other U.S. Food and Drug Administration–approved Humira biosimilars are expected to become available later in 2023.

Amjevita was approved by the FDA in September 2016 for multiple inflammatory diseases, including rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn’s disease, ulcerative colitis, and plaque psoriasis. The delayed launch was part of a global settlement with Humira’s manufacturer, AbbVie.

Humira (adalimumab) has been available since 2002 and is consistently one of the top-selling drugs in the United States. A single 40-mg Amjevita pen device will be available at two prices: a list price (wholesale acquisition cost) of $1,557.59, 55% below the current Humira list price, and a list price of $3,288.24, 5% below the current Humira list price, according to Amgen.

“Amgen’s goal is to provide broad access for patients by offering two options to health plans and pharmacy benefit managers,” the company said in the press release.

Patients are less likely to benefit from the more significant discount, said Marta Wosinska, PhD, a health care economist at the Brookings Institute in Washington, DC. It's expected that insurance companies will use the higher list price for Amjevita, she said, as this higher price will also likely have higher rebates. Rebates are payments to health insurance payers provided by drug manufacturers to promote use of an expensive drug. Some pharmacy benefit managers have already said that they plan to charge patients the same amount for Humira as its biosimilars, Dr. Wosinska said.

"For an existing patient, there's really no incentive for them to switch," she said in an interview.

So far only one insurance company, Kaiser Permanente, has plans to switch patients over to biosimilars, according to the health policy podcast Tradeoffs, and the insurer will stop covering Humira by the end of this year.

A version of this article first appeared on Medscape.com.

*This story was updated 2/1/2023.

To the Editor:

Generalized pustular psoriasis (GPP) is a rare but severe subtype of psoriasis that can present with systemic symptoms and organ failure, sometimes leading to hospitalization and even death.^1,2 Due to the rarity of this subtype and GPP being excluded from clinical trials for plaque psoriasis, there is limited information on the optimal treatment of this disease.

More than 20 systemic medications have been described in the literature for treating GPP, including systemic steroids, traditional immunosuppressants, retinoids, and biologics, which often are used in combination; none have been consistently effective.³ Among biologic therapies, the use of tumor necrosis factor α as well as IL-12/23 and IL-17 inhibitors has been reported, with the least amount of experience with IL-17 inhibitors.⁴

A 53-year-old Korean woman presented to the dermatology clinic for evaluation of a widespread painful rash involving the face, neck, torso, arms, and legs that had been treated intermittently with systemic steroids by her primary care physician for several months before presentation. She had no relevant medical or dermatologic history. She denied taking prescription or over-the-counter medications.

Physical examination revealed the patient was afebrile, but she reported general malaise and chills. She had widespread erythematous, annular, scaly plaques that coalesced into polycyclic plaques studded with nonfollicular-based pustules on the forehead, frontal hairline, neck, chest, abdomen, back, arms, and legs (Figure 1).

Two 4-mm punch biopsies were performed for hematoxylin and eosin staining and direct immunofluorescence. Histopathologic analysis showed prominent subcorneal neutrophilic pustules and spongiform collections of neutrophils in the spinous layer without notable eosinophils (Figure 2). Direct immunofluorescence was negative.

Based on the clinical history, physical examination, histopathology, and unremarkable drug history, a diagnosis of GPP was made. Initially, acitretin 25 mg/d was prescribed, but the patient was unable to start treatment because the cost of the drug was prohibitive. Her condition worsened, and she returned to the clinic 2 days later. Based on knowledge of an ongoing phase 3, open-label study for risankizumab in GPP, a sample of risankizumab 150 mg was administered subcutaneously in this patient. Three days later, most of the pustules on the upper half of the patient’s body had dried up and she began to desquamate from head to toe (Figure 3).The patient developed notable edema of the lower extremities, which required furosemide 20 mg/d andibuprofen 600 mg every 6 hours for symptom relief.

Ten days after the initial dose of risankizumab, the patient continued to steadily improve. All the pustules had dried up and she was already showing signs of re-epithelialization. Edema and pain also had notably improved. She received 2 additional samples of risankizumab 150 mg at weeks 4 and 16, at which point she was able to receive compassionate care through the drug manufacturer’s program. At follow-up 151 days after the initial dose of risankizumab, the patient’s skin was completely clear.

Generalized pustular psoriasis remains a difficult disease to study, given its rarity and unpredictable course. Spesolimab, a humanized anti–IL-36 receptor monoclonal antibody, was recently approved by the US Food and Drug Administration (FDA) for the treatment of GPP.⁵ In the pivotal trial (ClinicalTrials.gov Identifier NCT03782792),⁵ an astonishingly high 54% of patients (19/35) given a single dose of intravenous spesolimab reached the primary end point of no pustules at day 7. However, safety concerns, such as serious infections and severe cutaneous adverse reactions, as well as logistical challenges that come with intravenous administration for an acute disease, may prevent widespread adoption by community dermatologists.

Tumor necrosis factor α, IL-17, and IL-23 inhibitors currently are approved for the treatment of GPP in Japan, Thailand, and Taiwan based on small, nonrandomized, open-label studies.^6-10 More recently, results from a phase 3, randomized, open-label study to assess the efficacy and safety of 2 different dosing regimens of risankizumab with 8 Japanese patients with GPP were published.¹¹ However, there currently is only a single approved medication for GPP in Europe and the United States. Therefore, additional therapies, particularly those that have already been established in dermatology, would be welcome in treating this disease.

A number of questions still need to be answered regarding treating GPP with risankizumab:

• What is the optimal dose and schedule of this drug? Our patient received the standard 150-mg dose that is FDA approved for moderate to severe plaque psoriasis; would a higher dose, such as the FDA-approved 600-mg dosing used to treat Crohn disease, have led to a more rapid and durable response?¹²

• For how long should these patients be treated? Will their disease follow the same course as psoriasis vulgaris, requiring long-term, continuous treatment?

• An ongoing 5-year, open-label extension study of spesolimab might eventually answer that question and currently is recruiting participants (NCT03886246).

• Is there a way to predict a priori which patients will be responders? Biomarkers—especially through the use of tape stripping—are promising, but validation studies are still needed.¹³

• Because 69% (24/35) of enrolled patients in the treatment group of the spesolimab trial did not harbor a mutation of the IL36RN gene, how reliable is mutation status in predicting treatment response?⁵

Of note, some of these questions also apply to guttate psoriasis, a far more common subtype of psoriasis that also is worth exploring.

Nevertheless, these are exciting times for patients with GPP. What was once considered an obscure orphan disease is the focus of major recent publications³ and phase 3, randomized, placebo-controlled studies.⁵ We can be cautiously optimistic that in the next few years we will be in a better position to care for patients with GPP.

To the Editor:

Generalized pustular psoriasis (GPP) is a rare but severe subtype of psoriasis that can present with systemic symptoms and organ failure, sometimes leading to hospitalization and even death.^1,2 Due to the rarity of this subtype and GPP being excluded from clinical trials for plaque psoriasis, there is limited information on the optimal treatment of this disease.

More than 20 systemic medications have been described in the literature for treating GPP, including systemic steroids, traditional immunosuppressants, retinoids, and biologics, which often are used in combination; none have been consistently effective.³ Among biologic therapies, the use of tumor necrosis factor α as well as IL-12/23 and IL-17 inhibitors has been reported, with the least amount of experience with IL-17 inhibitors.⁴

A 53-year-old Korean woman presented to the dermatology clinic for evaluation of a widespread painful rash involving the face, neck, torso, arms, and legs that had been treated intermittently with systemic steroids by her primary care physician for several months before presentation. She had no relevant medical or dermatologic history. She denied taking prescription or over-the-counter medications.

Physical examination revealed the patient was afebrile, but she reported general malaise and chills. She had widespread erythematous, annular, scaly plaques that coalesced into polycyclic plaques studded with nonfollicular-based pustules on the forehead, frontal hairline, neck, chest, abdomen, back, arms, and legs (Figure 1).

Two 4-mm punch biopsies were performed for hematoxylin and eosin staining and direct immunofluorescence. Histopathologic analysis showed prominent subcorneal neutrophilic pustules and spongiform collections of neutrophils in the spinous layer without notable eosinophils (Figure 2). Direct immunofluorescence was negative.

Based on the clinical history, physical examination, histopathology, and unremarkable drug history, a diagnosis of GPP was made. Initially, acitretin 25 mg/d was prescribed, but the patient was unable to start treatment because the cost of the drug was prohibitive. Her condition worsened, and she returned to the clinic 2 days later. Based on knowledge of an ongoing phase 3, open-label study for risankizumab in GPP, a sample of risankizumab 150 mg was administered subcutaneously in this patient. Three days later, most of the pustules on the upper half of the patient’s body had dried up and she began to desquamate from head to toe (Figure 3).The patient developed notable edema of the lower extremities, which required furosemide 20 mg/d andibuprofen 600 mg every 6 hours for symptom relief.

Ten days after the initial dose of risankizumab, the patient continued to steadily improve. All the pustules had dried up and she was already showing signs of re-epithelialization. Edema and pain also had notably improved. She received 2 additional samples of risankizumab 150 mg at weeks 4 and 16, at which point she was able to receive compassionate care through the drug manufacturer’s program. At follow-up 151 days after the initial dose of risankizumab, the patient’s skin was completely clear.

Generalized pustular psoriasis remains a difficult disease to study, given its rarity and unpredictable course. Spesolimab, a humanized anti–IL-36 receptor monoclonal antibody, was recently approved by the US Food and Drug Administration (FDA) for the treatment of GPP.⁵ In the pivotal trial (ClinicalTrials.gov Identifier NCT03782792),⁵ an astonishingly high 54% of patients (19/35) given a single dose of intravenous spesolimab reached the primary end point of no pustules at day 7. However, safety concerns, such as serious infections and severe cutaneous adverse reactions, as well as logistical challenges that come with intravenous administration for an acute disease, may prevent widespread adoption by community dermatologists.

Tumor necrosis factor α, IL-17, and IL-23 inhibitors currently are approved for the treatment of GPP in Japan, Thailand, and Taiwan based on small, nonrandomized, open-label studies.^6-10 More recently, results from a phase 3, randomized, open-label study to assess the efficacy and safety of 2 different dosing regimens of risankizumab with 8 Japanese patients with GPP were published.¹¹ However, there currently is only a single approved medication for GPP in Europe and the United States. Therefore, additional therapies, particularly those that have already been established in dermatology, would be welcome in treating this disease.

A number of questions still need to be answered regarding treating GPP with risankizumab:

• What is the optimal dose and schedule of this drug? Our patient received the standard 150-mg dose that is FDA approved for moderate to severe plaque psoriasis; would a higher dose, such as the FDA-approved 600-mg dosing used to treat Crohn disease, have led to a more rapid and durable response?¹²

• For how long should these patients be treated? Will their disease follow the same course as psoriasis vulgaris, requiring long-term, continuous treatment?

• An ongoing 5-year, open-label extension study of spesolimab might eventually answer that question and currently is recruiting participants (NCT03886246).

• Is there a way to predict a priori which patients will be responders? Biomarkers—especially through the use of tape stripping—are promising, but validation studies are still needed.¹³

• Because 69% (24/35) of enrolled patients in the treatment group of the spesolimab trial did not harbor a mutation of the IL36RN gene, how reliable is mutation status in predicting treatment response?⁵

Of note, some of these questions also apply to guttate psoriasis, a far more common subtype of psoriasis that also is worth exploring.

Nevertheless, these are exciting times for patients with GPP. What was once considered an obscure orphan disease is the focus of major recent publications³ and phase 3, randomized, placebo-controlled studies.⁵ We can be cautiously optimistic that in the next few years we will be in a better position to care for patients with GPP.

To the Editor:

Generalized pustular psoriasis (GPP) is a rare but severe subtype of psoriasis that can present with systemic symptoms and organ failure, sometimes leading to hospitalization and even death.^1,2 Due to the rarity of this subtype and GPP being excluded from clinical trials for plaque psoriasis, there is limited information on the optimal treatment of this disease.

More than 20 systemic medications have been described in the literature for treating GPP, including systemic steroids, traditional immunosuppressants, retinoids, and biologics, which often are used in combination; none have been consistently effective.³ Among biologic therapies, the use of tumor necrosis factor α as well as IL-12/23 and IL-17 inhibitors has been reported, with the least amount of experience with IL-17 inhibitors.⁴

A 53-year-old Korean woman presented to the dermatology clinic for evaluation of a widespread painful rash involving the face, neck, torso, arms, and legs that had been treated intermittently with systemic steroids by her primary care physician for several months before presentation. She had no relevant medical or dermatologic history. She denied taking prescription or over-the-counter medications.

Physical examination revealed the patient was afebrile, but she reported general malaise and chills. She had widespread erythematous, annular, scaly plaques that coalesced into polycyclic plaques studded with nonfollicular-based pustules on the forehead, frontal hairline, neck, chest, abdomen, back, arms, and legs (Figure 1).

Two 4-mm punch biopsies were performed for hematoxylin and eosin staining and direct immunofluorescence. Histopathologic analysis showed prominent subcorneal neutrophilic pustules and spongiform collections of neutrophils in the spinous layer without notable eosinophils (Figure 2). Direct immunofluorescence was negative.

Based on the clinical history, physical examination, histopathology, and unremarkable drug history, a diagnosis of GPP was made. Initially, acitretin 25 mg/d was prescribed, but the patient was unable to start treatment because the cost of the drug was prohibitive. Her condition worsened, and she returned to the clinic 2 days later. Based on knowledge of an ongoing phase 3, open-label study for risankizumab in GPP, a sample of risankizumab 150 mg was administered subcutaneously in this patient. Three days later, most of the pustules on the upper half of the patient’s body had dried up and she began to desquamate from head to toe (Figure 3).The patient developed notable edema of the lower extremities, which required furosemide 20 mg/d andibuprofen 600 mg every 6 hours for symptom relief.

Ten days after the initial dose of risankizumab, the patient continued to steadily improve. All the pustules had dried up and she was already showing signs of re-epithelialization. Edema and pain also had notably improved. She received 2 additional samples of risankizumab 150 mg at weeks 4 and 16, at which point she was able to receive compassionate care through the drug manufacturer’s program. At follow-up 151 days after the initial dose of risankizumab, the patient’s skin was completely clear.

Generalized pustular psoriasis remains a difficult disease to study, given its rarity and unpredictable course. Spesolimab, a humanized anti–IL-36 receptor monoclonal antibody, was recently approved by the US Food and Drug Administration (FDA) for the treatment of GPP.⁵ In the pivotal trial (ClinicalTrials.gov Identifier NCT03782792),⁵ an astonishingly high 54% of patients (19/35) given a single dose of intravenous spesolimab reached the primary end point of no pustules at day 7. However, safety concerns, such as serious infections and severe cutaneous adverse reactions, as well as logistical challenges that come with intravenous administration for an acute disease, may prevent widespread adoption by community dermatologists.

Tumor necrosis factor α, IL-17, and IL-23 inhibitors currently are approved for the treatment of GPP in Japan, Thailand, and Taiwan based on small, nonrandomized, open-label studies.^6-10 More recently, results from a phase 3, randomized, open-label study to assess the efficacy and safety of 2 different dosing regimens of risankizumab with 8 Japanese patients with GPP were published.¹¹ However, there currently is only a single approved medication for GPP in Europe and the United States. Therefore, additional therapies, particularly those that have already been established in dermatology, would be welcome in treating this disease.

A number of questions still need to be answered regarding treating GPP with risankizumab:

• What is the optimal dose and schedule of this drug? Our patient received the standard 150-mg dose that is FDA approved for moderate to severe plaque psoriasis; would a higher dose, such as the FDA-approved 600-mg dosing used to treat Crohn disease, have led to a more rapid and durable response?¹²

• For how long should these patients be treated? Will their disease follow the same course as psoriasis vulgaris, requiring long-term, continuous treatment?

• An ongoing 5-year, open-label extension study of spesolimab might eventually answer that question and currently is recruiting participants (NCT03886246).

• Is there a way to predict a priori which patients will be responders? Biomarkers—especially through the use of tape stripping—are promising, but validation studies are still needed.¹³

• Because 69% (24/35) of enrolled patients in the treatment group of the spesolimab trial did not harbor a mutation of the IL36RN gene, how reliable is mutation status in predicting treatment response?⁵

Of note, some of these questions also apply to guttate psoriasis, a far more common subtype of psoriasis that also is worth exploring.

Nevertheless, these are exciting times for patients with GPP. What was once considered an obscure orphan disease is the focus of major recent publications³ and phase 3, randomized, placebo-controlled studies.⁵ We can be cautiously optimistic that in the next few years we will be in a better position to care for patients with GPP.

To the Editor:

Because the SARS-CoV-2 virus is constantly changing, routine vaccination to prevent COVID-19 infection is recommended. The messenger RNA (mRNA) vaccines from Pfizer-BioNTech and Moderna as well as the Ad26.COV2.S (Johnson & Johnson) and NVX-CoV2373 (Novavax) vaccines are the most commonly used COVID-19 vaccines in the United States. Adverse effects following vaccination against SARS-CoV-2 are well documented; recent studies report a small incidence of adverse effects in the general population, with most being minor (eg, headache, fever, muscle pain).^1,2 Interestingly, reports of exacerbation of psoriasis and new-onset psoriasis following COVID-19 vaccination suggest a potential association.^3,4 However, the literature investigating the vaccine adverse effect profile in this demographic is scarce. We examined the incidence of adverse effects from SARS-CoV-2 vaccines in patients with psoriasis.

This retrospective cohort study used the COVID-19 Research Database (https://covid19researchdatabase.org/) to examine the adverse effects following the first and second doses of the mRNA vaccines in patients with and without psoriasis. The sample size for the Ad26.COV2.S vaccine was too small to analyze.

Claims were evaluated from August to October 2021 for 2 diagnoses of psoriasis prior to January 1, 2020, using the International Classification of Diseases, Tenth Revision (ICD-10) code L40.9 to increase the positive predictive value and ensure that the diagnosis preceded the COVID-19 pandemic. Patients younger than 18 years and those who did not receive 2 doses of a SARS-CoV-2 vaccine were excluded. Controls who did not have a diagnosis of psoriasis were matched for age, sex, and hypertension at a 4:1 ratio. Hypertension represented the most common comorbidity that could feasibly be controlled for in this study population. Other comorbidities recorded included obesity, type 2 diabetes mellitus, congestive heart failure, asthma, chronic obstructive pulmonary disease, chronic ischemic heart disease, rhinitis, and chronic kidney disease.

Common adverse effects as long as 30 days after vaccination were identified using ICD-10 codes. Adverse effects of interest were anaphylactic reaction, initial encounter of adverse effect of viral vaccines, fever, allergic urticaria, weakness, altered mental status, malaise, allergic reaction, chest pain, symptoms involving circulatory or respiratory systems, localized rash, axillary lymphadenopathy, infection, and myocarditis.⁵ Poisson regression was performed using Stata 17 analytical software.

We identified 4273 patients with psoriasis and 17,092 controls who received mRNA COVID-19 vaccines (Table). Adjusted odds ratios (aORs) for doses 1 and 2 were calculated for each vaccine (eTable). Adverse effects with sufficient data to generate an aOR included weakness, altered mental status, malaise, chest pain, and symptoms involving the circulatory or respiratory system. The aORs for allergic urticaria and initial encounter of adverse effect of viral vaccines were only calculated for the Moderna mRNA vaccine due to low sample size.

This study demonstrated that patients with psoriasis do not appear to have a significantly increased risk of adverse effects from mRNA SARS-CoV-2 vaccines. Although the ORs in this study were not significant, most recorded adverse effects demonstrated an aOR less than 1, suggesting that there might be a lower risk of certain adverse effects in psoriasis patients. This could be explained by the immunomodulatory effects of certain systemic psoriasis treatments that might influence the adverse effect presentation.

The study is limited by the lack of treatment data, small sample size, and the fact that it did not assess flares or worsening of psoriasis with the vaccines. Underreporting of adverse effects by patients and underdiagnosis of adverse effects secondary to SARS-CoV-2 vaccines due to its novel nature, incompletely understood consequences, and limited ICD-10 codes associated with adverse effects all contributed to the small sample size.

Our findings suggest that the risk for immediate adverse effects from the mRNA SARS-CoV-2 vaccines is not increased among psoriasis patients. However, the impact of immunomodulatory agents on vaccine efficacy and expected adverse effects should be investigated. As more individuals receive the COVID-19 vaccine, the adverse effect profile in patients with psoriasis is an important area of investigation.

To the Editor:

Because the SARS-CoV-2 virus is constantly changing, routine vaccination to prevent COVID-19 infection is recommended. The messenger RNA (mRNA) vaccines from Pfizer-BioNTech and Moderna as well as the Ad26.COV2.S (Johnson & Johnson) and NVX-CoV2373 (Novavax) vaccines are the most commonly used COVID-19 vaccines in the United States. Adverse effects following vaccination against SARS-CoV-2 are well documented; recent studies report a small incidence of adverse effects in the general population, with most being minor (eg, headache, fever, muscle pain).^1,2 Interestingly, reports of exacerbation of psoriasis and new-onset psoriasis following COVID-19 vaccination suggest a potential association.^3,4 However, the literature investigating the vaccine adverse effect profile in this demographic is scarce. We examined the incidence of adverse effects from SARS-CoV-2 vaccines in patients with psoriasis.

This retrospective cohort study used the COVID-19 Research Database (https://covid19researchdatabase.org/) to examine the adverse effects following the first and second doses of the mRNA vaccines in patients with and without psoriasis. The sample size for the Ad26.COV2.S vaccine was too small to analyze.

Claims were evaluated from August to October 2021 for 2 diagnoses of psoriasis prior to January 1, 2020, using the International Classification of Diseases, Tenth Revision (ICD-10) code L40.9 to increase the positive predictive value and ensure that the diagnosis preceded the COVID-19 pandemic. Patients younger than 18 years and those who did not receive 2 doses of a SARS-CoV-2 vaccine were excluded. Controls who did not have a diagnosis of psoriasis were matched for age, sex, and hypertension at a 4:1 ratio. Hypertension represented the most common comorbidity that could feasibly be controlled for in this study population. Other comorbidities recorded included obesity, type 2 diabetes mellitus, congestive heart failure, asthma, chronic obstructive pulmonary disease, chronic ischemic heart disease, rhinitis, and chronic kidney disease.

Common adverse effects as long as 30 days after vaccination were identified using ICD-10 codes. Adverse effects of interest were anaphylactic reaction, initial encounter of adverse effect of viral vaccines, fever, allergic urticaria, weakness, altered mental status, malaise, allergic reaction, chest pain, symptoms involving circulatory or respiratory systems, localized rash, axillary lymphadenopathy, infection, and myocarditis.⁵ Poisson regression was performed using Stata 17 analytical software.

We identified 4273 patients with psoriasis and 17,092 controls who received mRNA COVID-19 vaccines (Table). Adjusted odds ratios (aORs) for doses 1 and 2 were calculated for each vaccine (eTable). Adverse effects with sufficient data to generate an aOR included weakness, altered mental status, malaise, chest pain, and symptoms involving the circulatory or respiratory system. The aORs for allergic urticaria and initial encounter of adverse effect of viral vaccines were only calculated for the Moderna mRNA vaccine due to low sample size.

This study demonstrated that patients with psoriasis do not appear to have a significantly increased risk of adverse effects from mRNA SARS-CoV-2 vaccines. Although the ORs in this study were not significant, most recorded adverse effects demonstrated an aOR less than 1, suggesting that there might be a lower risk of certain adverse effects in psoriasis patients. This could be explained by the immunomodulatory effects of certain systemic psoriasis treatments that might influence the adverse effect presentation.

The study is limited by the lack of treatment data, small sample size, and the fact that it did not assess flares or worsening of psoriasis with the vaccines. Underreporting of adverse effects by patients and underdiagnosis of adverse effects secondary to SARS-CoV-2 vaccines due to its novel nature, incompletely understood consequences, and limited ICD-10 codes associated with adverse effects all contributed to the small sample size.

Our findings suggest that the risk for immediate adverse effects from the mRNA SARS-CoV-2 vaccines is not increased among psoriasis patients. However, the impact of immunomodulatory agents on vaccine efficacy and expected adverse effects should be investigated. As more individuals receive the COVID-19 vaccine, the adverse effect profile in patients with psoriasis is an important area of investigation.

To the Editor:

Because the SARS-CoV-2 virus is constantly changing, routine vaccination to prevent COVID-19 infection is recommended. The messenger RNA (mRNA) vaccines from Pfizer-BioNTech and Moderna as well as the Ad26.COV2.S (Johnson & Johnson) and NVX-CoV2373 (Novavax) vaccines are the most commonly used COVID-19 vaccines in the United States. Adverse effects following vaccination against SARS-CoV-2 are well documented; recent studies report a small incidence of adverse effects in the general population, with most being minor (eg, headache, fever, muscle pain).^1,2 Interestingly, reports of exacerbation of psoriasis and new-onset psoriasis following COVID-19 vaccination suggest a potential association.^3,4 However, the literature investigating the vaccine adverse effect profile in this demographic is scarce. We examined the incidence of adverse effects from SARS-CoV-2 vaccines in patients with psoriasis.

This retrospective cohort study used the COVID-19 Research Database (https://covid19researchdatabase.org/) to examine the adverse effects following the first and second doses of the mRNA vaccines in patients with and without psoriasis. The sample size for the Ad26.COV2.S vaccine was too small to analyze.

Claims were evaluated from August to October 2021 for 2 diagnoses of psoriasis prior to January 1, 2020, using the International Classification of Diseases, Tenth Revision (ICD-10) code L40.9 to increase the positive predictive value and ensure that the diagnosis preceded the COVID-19 pandemic. Patients younger than 18 years and those who did not receive 2 doses of a SARS-CoV-2 vaccine were excluded. Controls who did not have a diagnosis of psoriasis were matched for age, sex, and hypertension at a 4:1 ratio. Hypertension represented the most common comorbidity that could feasibly be controlled for in this study population. Other comorbidities recorded included obesity, type 2 diabetes mellitus, congestive heart failure, asthma, chronic obstructive pulmonary disease, chronic ischemic heart disease, rhinitis, and chronic kidney disease.

Common adverse effects as long as 30 days after vaccination were identified using ICD-10 codes. Adverse effects of interest were anaphylactic reaction, initial encounter of adverse effect of viral vaccines, fever, allergic urticaria, weakness, altered mental status, malaise, allergic reaction, chest pain, symptoms involving circulatory or respiratory systems, localized rash, axillary lymphadenopathy, infection, and myocarditis.⁵ Poisson regression was performed using Stata 17 analytical software.

We identified 4273 patients with psoriasis and 17,092 controls who received mRNA COVID-19 vaccines (Table). Adjusted odds ratios (aORs) for doses 1 and 2 were calculated for each vaccine (eTable). Adverse effects with sufficient data to generate an aOR included weakness, altered mental status, malaise, chest pain, and symptoms involving the circulatory or respiratory system. The aORs for allergic urticaria and initial encounter of adverse effect of viral vaccines were only calculated for the Moderna mRNA vaccine due to low sample size.

This study demonstrated that patients with psoriasis do not appear to have a significantly increased risk of adverse effects from mRNA SARS-CoV-2 vaccines. Although the ORs in this study were not significant, most recorded adverse effects demonstrated an aOR less than 1, suggesting that there might be a lower risk of certain adverse effects in psoriasis patients. This could be explained by the immunomodulatory effects of certain systemic psoriasis treatments that might influence the adverse effect presentation.

The study is limited by the lack of treatment data, small sample size, and the fact that it did not assess flares or worsening of psoriasis with the vaccines. Underreporting of adverse effects by patients and underdiagnosis of adverse effects secondary to SARS-CoV-2 vaccines due to its novel nature, incompletely understood consequences, and limited ICD-10 codes associated with adverse effects all contributed to the small sample size.

Our findings suggest that the risk for immediate adverse effects from the mRNA SARS-CoV-2 vaccines is not increased among psoriasis patients. However, the impact of immunomodulatory agents on vaccine efficacy and expected adverse effects should be investigated. As more individuals receive the COVID-19 vaccine, the adverse effect profile in patients with psoriasis is an important area of investigation.

New treatments for psoriasis constitute an embarrassment of riches compared to any other area of dermatology. Despite the many advances over the last 25 years, additional topical and systemic treatments have recently become available. Gosh, it’s great!

In May 2022, once-daily tapinarof cream 1% was approved for the topical treatment of plaque psoriasis in adults.¹ Tapinarof was identified as a metabolite made by bacteria symbiotic to a nematode, allowing the nematode to infect insects.² Tapinarof’s anti-inflammatory effect extends to mammals. The drug works by activating the aryl hydrocarbon receptor, downregulating proinflammatory cytokines such as IL-17, and normalizing the expression of skin barrier proteins such as filaggrin.² In two 12-week, phase 3, randomized trials with 510 and 515 patients, respectively, 35% to 40% of tapinarof-treated psoriasis patients were clear or almost clear compared with only 6% of patients in the placebo group. The drug appears safe; common adverse events (AEs) included folliculitis, nasopharyngitis, contact dermatitis, headache, upper respiratory tract infection, and pruritus.³

A second new topical treatment for plaque psoriasis was approved in July 2022—once-daily roflumilast 0.3% cream—for patients 12 years and older.⁴ Similar to apremilast, roflumilast is a phosphodiesterase 4 inhibitor that blocks the degradation of cAMP and reduces the downstream production of inflammatory molecules implicated in psoriasis.⁵ In two 8-week, phase 3 clinical trials (ClinicalTrials.gov Identifiers NCT04211363 and NCT04211389)(N=881), approximately 40% of roflumilast-treated patients were clear or almost clear vs approximately 6% in the placebo group. Topical roflumilast was well-tolerated; the most common AEs included diarrhea, headache, insomnia, nausea, application-site pain, upper respiratory tract infection, and urinary tract infection.⁶

We have so many patients—and many more people with psoriasis who are not yet patients—with limited psoriasis who would be amenable to topical treatment but who are not responding to current treatments. There is considerable enthusiasm for the new topicals, but it is still questionable how much they will help our patients. The main reason the current topicals fail is poor adherence to the treatment. If we give these new treatments to patients who used existing topicals and failed, thereby inadvertently selecting patients with poor adherence to topicals, it will be surprising if the new treatments live up to expectations. Perhaps tapinarof and roflumilast will revolutionize the management of localized psoriasis; perhaps their impact will be similar to topical crisaborole— exciting in trials and less practical in real life. It may be that apremilast, which is now approved for psoriasis of any severity, will make a bigger difference for patients who can access it for limited psoriasis.

Deucravacitinib is a once-daily oral selective tyrosine kinase 2 inhibitor that blocks IL-23 and type I interferon signaling. It was approved for adults with moderate to severe plaque psoriasis in September 2021.⁷ We know patients want oral treatment; they ask for apremilast even though injections may be much more potent. In a 16-week, phase 3 clinical trial comparing daily deucravacitinib (n=332), apremilast (n=168), and placebo (n=166), rates of clear or almost clear were approximately 55% in the deucravacitinib group, 32% in the apremilast group, and 7% with placebo. The most common AEs included nasopharyngitis, upper respiratory tract infection, headache, diarrhea, and nausea.⁸ Although deucravacitinib is much more effective than apremilast, deucravacitinib will require monitoring and may have some risk for viral reactivation of herpes simplex and zoster (and hopefully not much else). Whether physicians view it as a replacement for apremilast, which requires no laboratory monitoring, remains to be seen.

Bimekizumab, a humanized monoclonal IgG1 antibody expected to receive US Food and Drug Administration approval in the coming months, inhibits both IL-17A and IL-17F and may become our most effective treatment of psoriasis. Although we are probably not hungering for a more effective psoriasis treatment (given our current embarrassment of riches), bimekizumab’s remarkably high efficacy for psoriatic arthritis may be a quantum leap forward, especially if no new safety signals are identified; bimekizumab treatment is associated with a higher risk of oral candidiasis than other currently available IL-17 antagonists.⁹ Biosimilars may reduce the cost of psoriasis management to the health system, but it seems unlikely that biosimilars will allow us to help patients who we cannot already help with the existing extensive psoriasis treatment armamentarium.

New treatments for psoriasis constitute an embarrassment of riches compared to any other area of dermatology. Despite the many advances over the last 25 years, additional topical and systemic treatments have recently become available. Gosh, it’s great!

In May 2022, once-daily tapinarof cream 1% was approved for the topical treatment of plaque psoriasis in adults.¹ Tapinarof was identified as a metabolite made by bacteria symbiotic to a nematode, allowing the nematode to infect insects.² Tapinarof’s anti-inflammatory effect extends to mammals. The drug works by activating the aryl hydrocarbon receptor, downregulating proinflammatory cytokines such as IL-17, and normalizing the expression of skin barrier proteins such as filaggrin.² In two 12-week, phase 3, randomized trials with 510 and 515 patients, respectively, 35% to 40% of tapinarof-treated psoriasis patients were clear or almost clear compared with only 6% of patients in the placebo group. The drug appears safe; common adverse events (AEs) included folliculitis, nasopharyngitis, contact dermatitis, headache, upper respiratory tract infection, and pruritus.³

A second new topical treatment for plaque psoriasis was approved in July 2022—once-daily roflumilast 0.3% cream—for patients 12 years and older.⁴ Similar to apremilast, roflumilast is a phosphodiesterase 4 inhibitor that blocks the degradation of cAMP and reduces the downstream production of inflammatory molecules implicated in psoriasis.⁵ In two 8-week, phase 3 clinical trials (ClinicalTrials.gov Identifiers NCT04211363 and NCT04211389)(N=881), approximately 40% of roflumilast-treated patients were clear or almost clear vs approximately 6% in the placebo group. Topical roflumilast was well-tolerated; the most common AEs included diarrhea, headache, insomnia, nausea, application-site pain, upper respiratory tract infection, and urinary tract infection.⁶

We have so many patients—and many more people with psoriasis who are not yet patients—with limited psoriasis who would be amenable to topical treatment but who are not responding to current treatments. There is considerable enthusiasm for the new topicals, but it is still questionable how much they will help our patients. The main reason the current topicals fail is poor adherence to the treatment. If we give these new treatments to patients who used existing topicals and failed, thereby inadvertently selecting patients with poor adherence to topicals, it will be surprising if the new treatments live up to expectations. Perhaps tapinarof and roflumilast will revolutionize the management of localized psoriasis; perhaps their impact will be similar to topical crisaborole— exciting in trials and less practical in real life. It may be that apremilast, which is now approved for psoriasis of any severity, will make a bigger difference for patients who can access it for limited psoriasis.

Deucravacitinib is a once-daily oral selective tyrosine kinase 2 inhibitor that blocks IL-23 and type I interferon signaling. It was approved for adults with moderate to severe plaque psoriasis in September 2021.⁷ We know patients want oral treatment; they ask for apremilast even though injections may be much more potent. In a 16-week, phase 3 clinical trial comparing daily deucravacitinib (n=332), apremilast (n=168), and placebo (n=166), rates of clear or almost clear were approximately 55% in the deucravacitinib group, 32% in the apremilast group, and 7% with placebo. The most common AEs included nasopharyngitis, upper respiratory tract infection, headache, diarrhea, and nausea.⁸ Although deucravacitinib is much more effective than apremilast, deucravacitinib will require monitoring and may have some risk for viral reactivation of herpes simplex and zoster (and hopefully not much else). Whether physicians view it as a replacement for apremilast, which requires no laboratory monitoring, remains to be seen.

Bimekizumab, a humanized monoclonal IgG1 antibody expected to receive US Food and Drug Administration approval in the coming months, inhibits both IL-17A and IL-17F and may become our most effective treatment of psoriasis. Although we are probably not hungering for a more effective psoriasis treatment (given our current embarrassment of riches), bimekizumab’s remarkably high efficacy for psoriatic arthritis may be a quantum leap forward, especially if no new safety signals are identified; bimekizumab treatment is associated with a higher risk of oral candidiasis than other currently available IL-17 antagonists.⁹ Biosimilars may reduce the cost of psoriasis management to the health system, but it seems unlikely that biosimilars will allow us to help patients who we cannot already help with the existing extensive psoriasis treatment armamentarium.

New treatments for psoriasis constitute an embarrassment of riches compared to any other area of dermatology. Despite the many advances over the last 25 years, additional topical and systemic treatments have recently become available. Gosh, it’s great!

In May 2022, once-daily tapinarof cream 1% was approved for the topical treatment of plaque psoriasis in adults.¹ Tapinarof was identified as a metabolite made by bacteria symbiotic to a nematode, allowing the nematode to infect insects.² Tapinarof’s anti-inflammatory effect extends to mammals. The drug works by activating the aryl hydrocarbon receptor, downregulating proinflammatory cytokines such as IL-17, and normalizing the expression of skin barrier proteins such as filaggrin.² In two 12-week, phase 3, randomized trials with 510 and 515 patients, respectively, 35% to 40% of tapinarof-treated psoriasis patients were clear or almost clear compared with only 6% of patients in the placebo group. The drug appears safe; common adverse events (AEs) included folliculitis, nasopharyngitis, contact dermatitis, headache, upper respiratory tract infection, and pruritus.³

A second new topical treatment for plaque psoriasis was approved in July 2022—once-daily roflumilast 0.3% cream—for patients 12 years and older.⁴ Similar to apremilast, roflumilast is a phosphodiesterase 4 inhibitor that blocks the degradation of cAMP and reduces the downstream production of inflammatory molecules implicated in psoriasis.⁵ In two 8-week, phase 3 clinical trials (ClinicalTrials.gov Identifiers NCT04211363 and NCT04211389)(N=881), approximately 40% of roflumilast-treated patients were clear or almost clear vs approximately 6% in the placebo group. Topical roflumilast was well-tolerated; the most common AEs included diarrhea, headache, insomnia, nausea, application-site pain, upper respiratory tract infection, and urinary tract infection.⁶

We have so many patients—and many more people with psoriasis who are not yet patients—with limited psoriasis who would be amenable to topical treatment but who are not responding to current treatments. There is considerable enthusiasm for the new topicals, but it is still questionable how much they will help our patients. The main reason the current topicals fail is poor adherence to the treatment. If we give these new treatments to patients who used existing topicals and failed, thereby inadvertently selecting patients with poor adherence to topicals, it will be surprising if the new treatments live up to expectations. Perhaps tapinarof and roflumilast will revolutionize the management of localized psoriasis; perhaps their impact will be similar to topical crisaborole— exciting in trials and less practical in real life. It may be that apremilast, which is now approved for psoriasis of any severity, will make a bigger difference for patients who can access it for limited psoriasis.

Deucravacitinib is a once-daily oral selective tyrosine kinase 2 inhibitor that blocks IL-23 and type I interferon signaling. It was approved for adults with moderate to severe plaque psoriasis in September 2021.⁷ We know patients want oral treatment; they ask for apremilast even though injections may be much more potent. In a 16-week, phase 3 clinical trial comparing daily deucravacitinib (n=332), apremilast (n=168), and placebo (n=166), rates of clear or almost clear were approximately 55% in the deucravacitinib group, 32% in the apremilast group, and 7% with placebo. The most common AEs included nasopharyngitis, upper respiratory tract infection, headache, diarrhea, and nausea.⁸ Although deucravacitinib is much more effective than apremilast, deucravacitinib will require monitoring and may have some risk for viral reactivation of herpes simplex and zoster (and hopefully not much else). Whether physicians view it as a replacement for apremilast, which requires no laboratory monitoring, remains to be seen.

Bimekizumab, a humanized monoclonal IgG1 antibody expected to receive US Food and Drug Administration approval in the coming months, inhibits both IL-17A and IL-17F and may become our most effective treatment of psoriasis. Although we are probably not hungering for a more effective psoriasis treatment (given our current embarrassment of riches), bimekizumab’s remarkably high efficacy for psoriatic arthritis may be a quantum leap forward, especially if no new safety signals are identified; bimekizumab treatment is associated with a higher risk of oral candidiasis than other currently available IL-17 antagonists.⁹ Biosimilars may reduce the cost of psoriasis management to the health system, but it seems unlikely that biosimilars will allow us to help patients who we cannot already help with the existing extensive psoriasis treatment armamentarium.

The landscape of psoriasis treatments has undergone rapid change within the last decade, and the dizzying speed of drug development has not slowed, with 4 notable entries into the psoriasis treatment armamentarium within the last year: tapinarof, roflumilast, deucravacitinib, and spesolimab. Several others are in late-stage development, and these therapies represent new mechanisms, pathways, and delivery systems that will meaningfully broaden the spectrum of treatment choices for our patients. However, it can be quite difficult to keep track of all of the medication options. This review aims to present the mechanisms and data on both newly available therapeutics for psoriasis and products in the pipeline that may have a major impact on our treatment paradigm for psoriasis in the near future.

Topical Treatments

Tapinarof—Tapinarof is a topical aryl hydrocarbon receptor (AhR)–modulating agent derived from a secondary metabolite produced by a bacterial symbiont of entomopathogenic nematodes.¹ Tapinarof binds and activates AhR, inducing a signaling cascade that suppresses the expression of helper T cells T_H17 and T_H22, upregulates skin barrier protein expression, and reduces epidermal oxidative stress.² This is a familiar mechanism, as AhR agonism is one of the pathways modulated by coal tar. Tapinarof’s overall effects on immune function, skin barrier integrity, and antioxidant activity show great promise for the treatment of plaque psoriasis.

Two phase 3 trials (N=1025) evaluated the efficacy and safety of once-daily tapinarof cream 1% for plaque psoriasis.³ A physician global assessment (PGA) score of 0/1 occurred in 35.4% to 40.2% of patients in the tapinarof group and in 6.0% of patients in the vehicle group. At week 12, 36.1% to 47.6% of patients treated with daily applications of tapinarof cream achieved a 75% reduction in their baseline psoriasis area and severity index (PASI 75) score compared with 6.9% to 10.2% in the vehicle group.³ In a long-term extension study, a substantial remittive effect of at least 4 months off tapinarof therapy was observed in patients who achieved complete clearance (PGA=0).⁴ Use of tapinarof cream was associated with folliculitis in up to 23.5% of patients.^3,4

Roflumilast—Phosphodiesterase 4 (PDE-4) is an intracellular enzyme involved in the regulation of cell proliferation, differentiation, and immune responses.⁵ The inhibition of PDE-4 decreases the expression of proinflammatory cytokines implicated in the pathogenesis of plaque psoriasis, such as tumor necrosis factor α, IFN-γ, and IL-2, IL-12, and IL-23.⁶ Phosphodiesterase 4–targeted therapies have been thoroughly explored to treat various inflammatory conditions, including atopic dermatitis and plaque psoriasis. The oral PDE-4 inhibitor apremilast was shown to achieve PASI 75 in approximately 30% of 562 patients, accompanied by severe gastrointestinal adverse events (AEs) including diarrhea and nausea associated with treatment.⁷ Local irritation from the topical PDE-4 inhibitor crisaborole for atopic dermatitis and psoriasis (where it only completed phase 2 trials) limits its widespread use. The lack of tolerable and effective treatment alternatives for psoriasis prompted the investigation of new PDE-4–targeted therapies.

Topical roflumilast is a selective, highly potent PDE-4 inhibitor with greater affinity for PDE-4 compared to crisaborole and apremilast.⁸ Two phase 3 trials (N=881) evaluated the efficacy and safety profile of roflumilast cream for plaque psoriasis, with a particular interest in its use for intertriginous areas.⁹ At week 8, 37.5% to 42.4% of roflumilast-treated patients achieved investigator global assessment (IGA) success compared with 6.1% to 6.9% of vehicle-treated patients. Intertriginous IGA success was observed in 68.1% to 71.2% of patients treated with roflumilast cream compared with 13.8% to 18.5% of vehicle-treated patients. At 8-week follow-up, 39.0% to 41.6% of roflumilast-treated patients achieved PASI 75 vs 5.3% to 7.6% of patients in the vehicle group. Few stinging, burning, or application-site reactions were reported with roflumilast, along with rare instances of gastrointestinal AEs (<4%).⁹

Oral Therapy

Deucravacitinib—Tyrosine kinase 2 (TYK2) mediates the intracellular signaling of the T_H17 and T_H1 inflammatory cytokines IL-12/IL-23 and type I interferons, respectively, the former of which are critical in the development of psoriasis via the Janus kinase (JAK) signal transducer and activator of transcription pathway.¹⁰ Deucravacitinib is an oral selective TYK2 allosteric inhibitor that binds to the regulatory domain of the enzyme rather than the active catalytic domain, where other TYK2 and JAK1, JAK2, and JAK3 inhibitors bind.¹¹ This unique inhibitory mechanism accounts for the high functional selectivity of deucravacitinib for TYK2 vs the closely related JAK1, JAK2, and JAK3 kinases, thus avoiding the pitfall of prior JAK inhibitors that were associated with major AEs, including an increased risk for serious infections, malignancies, and thrombosis.¹² The selective suppression of the inflammatory TYK2 pathway has the potential to shift future therapeutic targets to a narrower range of receptors that may contribute to favorable benefit-risk profiles.

Two phase 3 trials (N=1686) compared the efficacy and safety of deucravacitinib vs placebo and apremilast in adults with moderate to severe plaque psoriasis.^13,14 At week 16, 53.0% to 58.4% of deucravacitinib-treated patients achieved PASI 75 compared with 35.1% to 39.8% of apremilast-treated patients. At 16-week follow-up, static PGA response was observed in 49.5% to 53.6% of patients in the deucravacitinib group and 32.1% to 33.9% of the apremilast group. The most frequent AEs associated with deucravacitinib therapy were nasopharyngitis and upper respiratory tract infection, whereas headache, diarrhea, and nausea were more common with apremilast. Treatment with deucravacitinib caused no meaningful changes in laboratory parameters, which are known to change with JAK1, JAK2, and JAK3 inhibitors.^13,14 A long-term extension study demonstrated that deucravacitinib had persistent efficacy and consistent safety for up to 2 years.¹⁵

Novel oral allosteric TYK2 inhibitors—VTX958 and NDI-034858—and the competitive TYK2 inhibitor PF-06826647 are being developed. Theoretically, these new allosteric inhibitors possess unique structural properties to provide greater TYK2 suppression while bypassing JAK1, JAK2, and JAK3 pathways that may contribute to improved efficacy and safety profiles compared with other TYK2 inhibitors such as deucravacitinib. The results of a phase 1b trial (ClinicalTrials.gov Identifier NCT04999839) showed a dose-dependent reduction of disease severity associated with NDI-034858 treatment for patients with moderate to severe plaque psoriasis, albeit in only 26 patients. At week 4, PASI 50 was achieved in 13%, 57%, and 40% of patients in the 5-, 10-, and 30-mg groups, respectively, compared with 0% in the placebo group.¹⁶ In a phase 2 trial of 179 patients, 46.5% and 33.0% of patients treated with 400 and 200 mg of PF-06826647, respectively, achieved PASI 90 at week 16. Conversely, dose-dependent laboratory abnormalities were observed with PF-06826647, including anemia, neutropenia, and increases in creatine phosphokinase.¹⁷ At high concentrations, PF-06826647 may disrupt JAK signaling pathways involved in hematopoiesis and renal functions owing to its mode of action as a competitive inhibitor. Overall, these agents are much farther from market, and long-term studies with larger diverse patient cohorts are required to adequately assess the efficacy and safety data of these novel oral TYK2 inhibitors for patients with psoriasis.

EDP1815—EDP1815 is an oral preparation of a single strain of Prevotella histicola being developed for the treatment of inflammatory diseases, including psoriasis. EDP1815 interacts with host intestinal immune cells through the small intestinal axis (SINTAX) to suppress systemic inflammation across the T_H1, T_H2, and T_H17 pathways. Therapy triggers broad immunomodulatory effects without causing systemic absorption, colonic colonization, or modification of the gut microbiome.¹⁸ In a phase 2 study (NCT04603027), the primary end point analysis, mean percentage change in PASI between treatment and placebo, demonstrated that at week 16, EDP1815 was superior to placebo with 80% to 90% probability across each cohort. At week 16, 25% to 32% of patients across the 3 cohorts treated with EDP1815 achieved PASI 50 compared with 12% of patients receiving placebo. Gastrointestinal AEs were comparable between treatment and placebo groups. These results suggest that SINTAX-targeted therapies may provide efficacious and safe immunomodulatory effects for patients with mild to moderate psoriasis, who often have limited treatment options. Although improvements may be mild, SINTAX-targeted therapies can be seen as a particularly attractive adjunctive treatment for patients with severe psoriasis taking other medications or as part of a treatment approach for a patient with milder psoriasis.

Biologics

Bimekizumab—Bimekizumab is a monoclonal IgG1 antibody that selectively inhibits IL-17A and IL-17F. Although IL-17A is a more potent cytokine, IL-17F may be more highly expressed in psoriatic lesional skin and independently contribute to the activation of proinflammatory signaling pathways implicated in the pathophysiology of psoriasis.¹⁹ Evidence suggests that dual inhibition of IL-17A and IL-17F may provide more complete suppression of inflammation and improved clinical responses than IL-17A inhibition alone.²⁰

Prior bimekizumab phase 3 clinical studies have shown both rapid and durable clinical improvements in skin clearance compared with placebo.²¹ Three phase 3 trials—BE VIVID (N=567),²² BE SURE (N=478),²³ and BE RADIANT (N=743)²⁴—assessed the efficacy and safety of bimekizumab vs the IL-12/IL-23 inhibitor ustekinumab, the tumor necrosis factor inhibitor adalimumab, and the selective IL-17A inhibitor secukinumab, respectively. At week 4, significantly more patients treated with bimekizumab (71%–77%) achieved PASI 75 than patients treated with ustekinumab (15%; P<.0001), adalimumab (31.4%; P<.001), or secukinumab (47.3%; P<.001).^22-24 After 16 weeks of treatment, PASI 90 was achieved by 85% to 86.2%, 50%, and 47.2% of patients treated with bimekizumab, ustekinumab, and adalimumab, respectively.^22,23 At week 16, PASI 100 was observed in 59% to 61.7%, 21%, 23.9%, and 48.9% of patients treated with bimekizumab, ustekinumab, adalimumab, and secukinumab, respectively. An IGA response (score of 0/1) at week 16 was achieved by 84% to 85.5%, 53%, 57.2%, and 78.6% of patients receiving bimekizumab, ustekinumab, adalimumab, and secukinumab, respectively.^22-24

The most common AEs in bimekizumab-treated patients were nasopharyngitis, oral candidiasis, and upper respiratory tract infection.^22-24 The dual inhibition of IL-17A and IL-17F suppresses host defenses against Candida at the oral mucosa, increasing the incidence of bimekizumab-associated oral candidiasis.²⁵ Despite the increased risk of Candida infections, these data suggest that inhibition of both IL-17A and IL-17F with bimekizumab may provide faster and greater clinical benefit for patients with moderate to severe plaque psoriasis than inhibition of IL-17A alone and other biologic therapies, as the PASI 100 clearance rates across the multiple comparator trials and the placebo-controlled pivotal trial are consistently the highest among any biologic for the treatment of psoriasis.

Spesolimab—The IL-36 pathway and IL-36 receptor genes have been linked to the pathogenesis of generalized pustular psoriasis.²⁶ In a phase 2 trial, 19 of 35 patients (54%) receiving an intravenous dose of spesolimab, an IL-36 receptor inhibitor, had a generalized pustular psoriasis PGA pustulation subscore of 0 (no visible pustules) at the end of week 1 vs 6% of patients in the placebo group.²⁷ A generalized pustular psoriasis PGA total score of 0 or 1 was observed in 43% (15/35) of spesolimab-treated patients compared with 11% (2/18) of patients in the placebo group. The most common AEs in patients treated with spesolimab were minor infections.²⁷ Two open-label phase 3 trials—NCT05200247 and NCT05239039—are underway to determine the long-term efficacy and safety of spesolimab in patients with generalized pustular psoriasis.

Conclusion

Although we have seen a renaissance in psoriasis therapies with the advent of biologics in the last 20 years, recent evidence shows that more innovation is underway. Just in the last year, 2 new mechanisms for treating psoriasis topically without steroids have come to fruition, and there have not been truly novel mechanisms for treating psoriasis topically since approvals for tazarotene and calcipotriene in the 1990s. An entirely new class—TYK2 inhibitors—was developed and landed in psoriasis first, greatly improving the efficacy measures attained with oral medications in general. Finally, an orphan diagnosis got its due with an ambitiously designed study looking at a previously unheard-of 1-week end point, but it comes for one of the few true dermatologic emergencies we encounter, generalized pustular psoriasis. We are fortunate to have so many meaningful new treatments available to us, and it is invigorating to see that even more efficacious biologics and treatments are coming, along with novel concepts such as a treatment affecting the microbiome. Now, we just need to make sure that our patients have the access they deserve to the wide array of available treatments.

The landscape of psoriasis treatments has undergone rapid change within the last decade, and the dizzying speed of drug development has not slowed, with 4 notable entries into the psoriasis treatment armamentarium within the last year: tapinarof, roflumilast, deucravacitinib, and spesolimab. Several others are in late-stage development, and these therapies represent new mechanisms, pathways, and delivery systems that will meaningfully broaden the spectrum of treatment choices for our patients. However, it can be quite difficult to keep track of all of the medication options. This review aims to present the mechanisms and data on both newly available therapeutics for psoriasis and products in the pipeline that may have a major impact on our treatment paradigm for psoriasis in the near future.

Topical Treatments

Tapinarof—Tapinarof is a topical aryl hydrocarbon receptor (AhR)–modulating agent derived from a secondary metabolite produced by a bacterial symbiont of entomopathogenic nematodes.¹ Tapinarof binds and activates AhR, inducing a signaling cascade that suppresses the expression of helper T cells T_H17 and T_H22, upregulates skin barrier protein expression, and reduces epidermal oxidative stress.² This is a familiar mechanism, as AhR agonism is one of the pathways modulated by coal tar. Tapinarof’s overall effects on immune function, skin barrier integrity, and antioxidant activity show great promise for the treatment of plaque psoriasis.

Two phase 3 trials (N=1025) evaluated the efficacy and safety of once-daily tapinarof cream 1% for plaque psoriasis.³ A physician global assessment (PGA) score of 0/1 occurred in 35.4% to 40.2% of patients in the tapinarof group and in 6.0% of patients in the vehicle group. At week 12, 36.1% to 47.6% of patients treated with daily applications of tapinarof cream achieved a 75% reduction in their baseline psoriasis area and severity index (PASI 75) score compared with 6.9% to 10.2% in the vehicle group.³ In a long-term extension study, a substantial remittive effect of at least 4 months off tapinarof therapy was observed in patients who achieved complete clearance (PGA=0).⁴ Use of tapinarof cream was associated with folliculitis in up to 23.5% of patients.^3,4

Roflumilast—Phosphodiesterase 4 (PDE-4) is an intracellular enzyme involved in the regulation of cell proliferation, differentiation, and immune responses.⁵ The inhibition of PDE-4 decreases the expression of proinflammatory cytokines implicated in the pathogenesis of plaque psoriasis, such as tumor necrosis factor α, IFN-γ, and IL-2, IL-12, and IL-23.⁶ Phosphodiesterase 4–targeted therapies have been thoroughly explored to treat various inflammatory conditions, including atopic dermatitis and plaque psoriasis. The oral PDE-4 inhibitor apremilast was shown to achieve PASI 75 in approximately 30% of 562 patients, accompanied by severe gastrointestinal adverse events (AEs) including diarrhea and nausea associated with treatment.⁷ Local irritation from the topical PDE-4 inhibitor crisaborole for atopic dermatitis and psoriasis (where it only completed phase 2 trials) limits its widespread use. The lack of tolerable and effective treatment alternatives for psoriasis prompted the investigation of new PDE-4–targeted therapies.

Topical roflumilast is a selective, highly potent PDE-4 inhibitor with greater affinity for PDE-4 compared to crisaborole and apremilast.⁸ Two phase 3 trials (N=881) evaluated the efficacy and safety profile of roflumilast cream for plaque psoriasis, with a particular interest in its use for intertriginous areas.⁹ At week 8, 37.5% to 42.4% of roflumilast-treated patients achieved investigator global assessment (IGA) success compared with 6.1% to 6.9% of vehicle-treated patients. Intertriginous IGA success was observed in 68.1% to 71.2% of patients treated with roflumilast cream compared with 13.8% to 18.5% of vehicle-treated patients. At 8-week follow-up, 39.0% to 41.6% of roflumilast-treated patients achieved PASI 75 vs 5.3% to 7.6% of patients in the vehicle group. Few stinging, burning, or application-site reactions were reported with roflumilast, along with rare instances of gastrointestinal AEs (<4%).⁹

Oral Therapy

Deucravacitinib—Tyrosine kinase 2 (TYK2) mediates the intracellular signaling of the T_H17 and T_H1 inflammatory cytokines IL-12/IL-23 and type I interferons, respectively, the former of which are critical in the development of psoriasis via the Janus kinase (JAK) signal transducer and activator of transcription pathway.¹⁰ Deucravacitinib is an oral selective TYK2 allosteric inhibitor that binds to the regulatory domain of the enzyme rather than the active catalytic domain, where other TYK2 and JAK1, JAK2, and JAK3 inhibitors bind.¹¹ This unique inhibitory mechanism accounts for the high functional selectivity of deucravacitinib for TYK2 vs the closely related JAK1, JAK2, and JAK3 kinases, thus avoiding the pitfall of prior JAK inhibitors that were associated with major AEs, including an increased risk for serious infections, malignancies, and thrombosis.¹² The selective suppression of the inflammatory TYK2 pathway has the potential to shift future therapeutic targets to a narrower range of receptors that may contribute to favorable benefit-risk profiles.

Two phase 3 trials (N=1686) compared the efficacy and safety of deucravacitinib vs placebo and apremilast in adults with moderate to severe plaque psoriasis.^13,14 At week 16, 53.0% to 58.4% of deucravacitinib-treated patients achieved PASI 75 compared with 35.1% to 39.8% of apremilast-treated patients. At 16-week follow-up, static PGA response was observed in 49.5% to 53.6% of patients in the deucravacitinib group and 32.1% to 33.9% of the apremilast group. The most frequent AEs associated with deucravacitinib therapy were nasopharyngitis and upper respiratory tract infection, whereas headache, diarrhea, and nausea were more common with apremilast. Treatment with deucravacitinib caused no meaningful changes in laboratory parameters, which are known to change with JAK1, JAK2, and JAK3 inhibitors.^13,14 A long-term extension study demonstrated that deucravacitinib had persistent efficacy and consistent safety for up to 2 years.¹⁵

Novel oral allosteric TYK2 inhibitors—VTX958 and NDI-034858—and the competitive TYK2 inhibitor PF-06826647 are being developed. Theoretically, these new allosteric inhibitors possess unique structural properties to provide greater TYK2 suppression while bypassing JAK1, JAK2, and JAK3 pathways that may contribute to improved efficacy and safety profiles compared with other TYK2 inhibitors such as deucravacitinib. The results of a phase 1b trial (ClinicalTrials.gov Identifier NCT04999839) showed a dose-dependent reduction of disease severity associated with NDI-034858 treatment for patients with moderate to severe plaque psoriasis, albeit in only 26 patients. At week 4, PASI 50 was achieved in 13%, 57%, and 40% of patients in the 5-, 10-, and 30-mg groups, respectively, compared with 0% in the placebo group.¹⁶ In a phase 2 trial of 179 patients, 46.5% and 33.0% of patients treated with 400 and 200 mg of PF-06826647, respectively, achieved PASI 90 at week 16. Conversely, dose-dependent laboratory abnormalities were observed with PF-06826647, including anemia, neutropenia, and increases in creatine phosphokinase.¹⁷ At high concentrations, PF-06826647 may disrupt JAK signaling pathways involved in hematopoiesis and renal functions owing to its mode of action as a competitive inhibitor. Overall, these agents are much farther from market, and long-term studies with larger diverse patient cohorts are required to adequately assess the efficacy and safety data of these novel oral TYK2 inhibitors for patients with psoriasis.

EDP1815—EDP1815 is an oral preparation of a single strain of Prevotella histicola being developed for the treatment of inflammatory diseases, including psoriasis. EDP1815 interacts with host intestinal immune cells through the small intestinal axis (SINTAX) to suppress systemic inflammation across the T_H1, T_H2, and T_H17 pathways. Therapy triggers broad immunomodulatory effects without causing systemic absorption, colonic colonization, or modification of the gut microbiome.¹⁸ In a phase 2 study (NCT04603027), the primary end point analysis, mean percentage change in PASI between treatment and placebo, demonstrated that at week 16, EDP1815 was superior to placebo with 80% to 90% probability across each cohort. At week 16, 25% to 32% of patients across the 3 cohorts treated with EDP1815 achieved PASI 50 compared with 12% of patients receiving placebo. Gastrointestinal AEs were comparable between treatment and placebo groups. These results suggest that SINTAX-targeted therapies may provide efficacious and safe immunomodulatory effects for patients with mild to moderate psoriasis, who often have limited treatment options. Although improvements may be mild, SINTAX-targeted therapies can be seen as a particularly attractive adjunctive treatment for patients with severe psoriasis taking other medications or as part of a treatment approach for a patient with milder psoriasis.

Biologics

Bimekizumab—Bimekizumab is a monoclonal IgG1 antibody that selectively inhibits IL-17A and IL-17F. Although IL-17A is a more potent cytokine, IL-17F may be more highly expressed in psoriatic lesional skin and independently contribute to the activation of proinflammatory signaling pathways implicated in the pathophysiology of psoriasis.¹⁹ Evidence suggests that dual inhibition of IL-17A and IL-17F may provide more complete suppression of inflammation and improved clinical responses than IL-17A inhibition alone.²⁰

Prior bimekizumab phase 3 clinical studies have shown both rapid and durable clinical improvements in skin clearance compared with placebo.²¹ Three phase 3 trials—BE VIVID (N=567),²² BE SURE (N=478),²³ and BE RADIANT (N=743)²⁴—assessed the efficacy and safety of bimekizumab vs the IL-12/IL-23 inhibitor ustekinumab, the tumor necrosis factor inhibitor adalimumab, and the selective IL-17A inhibitor secukinumab, respectively. At week 4, significantly more patients treated with bimekizumab (71%–77%) achieved PASI 75 than patients treated with ustekinumab (15%; P<.0001), adalimumab (31.4%; P<.001), or secukinumab (47.3%; P<.001).^22-24 After 16 weeks of treatment, PASI 90 was achieved by 85% to 86.2%, 50%, and 47.2% of patients treated with bimekizumab, ustekinumab, and adalimumab, respectively.^22,23 At week 16, PASI 100 was observed in 59% to 61.7%, 21%, 23.9%, and 48.9% of patients treated with bimekizumab, ustekinumab, adalimumab, and secukinumab, respectively. An IGA response (score of 0/1) at week 16 was achieved by 84% to 85.5%, 53%, 57.2%, and 78.6% of patients receiving bimekizumab, ustekinumab, adalimumab, and secukinumab, respectively.^22-24

The most common AEs in bimekizumab-treated patients were nasopharyngitis, oral candidiasis, and upper respiratory tract infection.^22-24 The dual inhibition of IL-17A and IL-17F suppresses host defenses against Candida at the oral mucosa, increasing the incidence of bimekizumab-associated oral candidiasis.²⁵ Despite the increased risk of Candida infections, these data suggest that inhibition of both IL-17A and IL-17F with bimekizumab may provide faster and greater clinical benefit for patients with moderate to severe plaque psoriasis than inhibition of IL-17A alone and other biologic therapies, as the PASI 100 clearance rates across the multiple comparator trials and the placebo-controlled pivotal trial are consistently the highest among any biologic for the treatment of psoriasis.

Spesolimab—The IL-36 pathway and IL-36 receptor genes have been linked to the pathogenesis of generalized pustular psoriasis.²⁶ In a phase 2 trial, 19 of 35 patients (54%) receiving an intravenous dose of spesolimab, an IL-36 receptor inhibitor, had a generalized pustular psoriasis PGA pustulation subscore of 0 (no visible pustules) at the end of week 1 vs 6% of patients in the placebo group.²⁷ A generalized pustular psoriasis PGA total score of 0 or 1 was observed in 43% (15/35) of spesolimab-treated patients compared with 11% (2/18) of patients in the placebo group. The most common AEs in patients treated with spesolimab were minor infections.²⁷ Two open-label phase 3 trials—NCT05200247 and NCT05239039—are underway to determine the long-term efficacy and safety of spesolimab in patients with generalized pustular psoriasis.

Conclusion

Although we have seen a renaissance in psoriasis therapies with the advent of biologics in the last 20 years, recent evidence shows that more innovation is underway. Just in the last year, 2 new mechanisms for treating psoriasis topically without steroids have come to fruition, and there have not been truly novel mechanisms for treating psoriasis topically since approvals for tazarotene and calcipotriene in the 1990s. An entirely new class—TYK2 inhibitors—was developed and landed in psoriasis first, greatly improving the efficacy measures attained with oral medications in general. Finally, an orphan diagnosis got its due with an ambitiously designed study looking at a previously unheard-of 1-week end point, but it comes for one of the few true dermatologic emergencies we encounter, generalized pustular psoriasis. We are fortunate to have so many meaningful new treatments available to us, and it is invigorating to see that even more efficacious biologics and treatments are coming, along with novel concepts such as a treatment affecting the microbiome. Now, we just need to make sure that our patients have the access they deserve to the wide array of available treatments.

The landscape of psoriasis treatments has undergone rapid change within the last decade, and the dizzying speed of drug development has not slowed, with 4 notable entries into the psoriasis treatment armamentarium within the last year: tapinarof, roflumilast, deucravacitinib, and spesolimab. Several others are in late-stage development, and these therapies represent new mechanisms, pathways, and delivery systems that will meaningfully broaden the spectrum of treatment choices for our patients. However, it can be quite difficult to keep track of all of the medication options. This review aims to present the mechanisms and data on both newly available therapeutics for psoriasis and products in the pipeline that may have a major impact on our treatment paradigm for psoriasis in the near future.

Topical Treatments

Tapinarof—Tapinarof is a topical aryl hydrocarbon receptor (AhR)–modulating agent derived from a secondary metabolite produced by a bacterial symbiont of entomopathogenic nematodes.¹ Tapinarof binds and activates AhR, inducing a signaling cascade that suppresses the expression of helper T cells T_H17 and T_H22, upregulates skin barrier protein expression, and reduces epidermal oxidative stress.² This is a familiar mechanism, as AhR agonism is one of the pathways modulated by coal tar. Tapinarof’s overall effects on immune function, skin barrier integrity, and antioxidant activity show great promise for the treatment of plaque psoriasis.

Two phase 3 trials (N=1025) evaluated the efficacy and safety of once-daily tapinarof cream 1% for plaque psoriasis.³ A physician global assessment (PGA) score of 0/1 occurred in 35.4% to 40.2% of patients in the tapinarof group and in 6.0% of patients in the vehicle group. At week 12, 36.1% to 47.6% of patients treated with daily applications of tapinarof cream achieved a 75% reduction in their baseline psoriasis area and severity index (PASI 75) score compared with 6.9% to 10.2% in the vehicle group.³ In a long-term extension study, a substantial remittive effect of at least 4 months off tapinarof therapy was observed in patients who achieved complete clearance (PGA=0).⁴ Use of tapinarof cream was associated with folliculitis in up to 23.5% of patients.^3,4

Roflumilast—Phosphodiesterase 4 (PDE-4) is an intracellular enzyme involved in the regulation of cell proliferation, differentiation, and immune responses.⁵ The inhibition of PDE-4 decreases the expression of proinflammatory cytokines implicated in the pathogenesis of plaque psoriasis, such as tumor necrosis factor α, IFN-γ, and IL-2, IL-12, and IL-23.⁶ Phosphodiesterase 4–targeted therapies have been thoroughly explored to treat various inflammatory conditions, including atopic dermatitis and plaque psoriasis. The oral PDE-4 inhibitor apremilast was shown to achieve PASI 75 in approximately 30% of 562 patients, accompanied by severe gastrointestinal adverse events (AEs) including diarrhea and nausea associated with treatment.⁷ Local irritation from the topical PDE-4 inhibitor crisaborole for atopic dermatitis and psoriasis (where it only completed phase 2 trials) limits its widespread use. The lack of tolerable and effective treatment alternatives for psoriasis prompted the investigation of new PDE-4–targeted therapies.

Topical roflumilast is a selective, highly potent PDE-4 inhibitor with greater affinity for PDE-4 compared to crisaborole and apremilast.⁸ Two phase 3 trials (N=881) evaluated the efficacy and safety profile of roflumilast cream for plaque psoriasis, with a particular interest in its use for intertriginous areas.⁹ At week 8, 37.5% to 42.4% of roflumilast-treated patients achieved investigator global assessment (IGA) success compared with 6.1% to 6.9% of vehicle-treated patients. Intertriginous IGA success was observed in 68.1% to 71.2% of patients treated with roflumilast cream compared with 13.8% to 18.5% of vehicle-treated patients. At 8-week follow-up, 39.0% to 41.6% of roflumilast-treated patients achieved PASI 75 vs 5.3% to 7.6% of patients in the vehicle group. Few stinging, burning, or application-site reactions were reported with roflumilast, along with rare instances of gastrointestinal AEs (<4%).⁹

Oral Therapy

Deucravacitinib—Tyrosine kinase 2 (TYK2) mediates the intracellular signaling of the T_H17 and T_H1 inflammatory cytokines IL-12/IL-23 and type I interferons, respectively, the former of which are critical in the development of psoriasis via the Janus kinase (JAK) signal transducer and activator of transcription pathway.¹⁰ Deucravacitinib is an oral selective TYK2 allosteric inhibitor that binds to the regulatory domain of the enzyme rather than the active catalytic domain, where other TYK2 and JAK1, JAK2, and JAK3 inhibitors bind.¹¹ This unique inhibitory mechanism accounts for the high functional selectivity of deucravacitinib for TYK2 vs the closely related JAK1, JAK2, and JAK3 kinases, thus avoiding the pitfall of prior JAK inhibitors that were associated with major AEs, including an increased risk for serious infections, malignancies, and thrombosis.¹² The selective suppression of the inflammatory TYK2 pathway has the potential to shift future therapeutic targets to a narrower range of receptors that may contribute to favorable benefit-risk profiles.

Two phase 3 trials (N=1686) compared the efficacy and safety of deucravacitinib vs placebo and apremilast in adults with moderate to severe plaque psoriasis.^13,14 At week 16, 53.0% to 58.4% of deucravacitinib-treated patients achieved PASI 75 compared with 35.1% to 39.8% of apremilast-treated patients. At 16-week follow-up, static PGA response was observed in 49.5% to 53.6% of patients in the deucravacitinib group and 32.1% to 33.9% of the apremilast group. The most frequent AEs associated with deucravacitinib therapy were nasopharyngitis and upper respiratory tract infection, whereas headache, diarrhea, and nausea were more common with apremilast. Treatment with deucravacitinib caused no meaningful changes in laboratory parameters, which are known to change with JAK1, JAK2, and JAK3 inhibitors.^13,14 A long-term extension study demonstrated that deucravacitinib had persistent efficacy and consistent safety for up to 2 years.¹⁵

Novel oral allosteric TYK2 inhibitors—VTX958 and NDI-034858—and the competitive TYK2 inhibitor PF-06826647 are being developed. Theoretically, these new allosteric inhibitors possess unique structural properties to provide greater TYK2 suppression while bypassing JAK1, JAK2, and JAK3 pathways that may contribute to improved efficacy and safety profiles compared with other TYK2 inhibitors such as deucravacitinib. The results of a phase 1b trial (ClinicalTrials.gov Identifier NCT04999839) showed a dose-dependent reduction of disease severity associated with NDI-034858 treatment for patients with moderate to severe plaque psoriasis, albeit in only 26 patients. At week 4, PASI 50 was achieved in 13%, 57%, and 40% of patients in the 5-, 10-, and 30-mg groups, respectively, compared with 0% in the placebo group.¹⁶ In a phase 2 trial of 179 patients, 46.5% and 33.0% of patients treated with 400 and 200 mg of PF-06826647, respectively, achieved PASI 90 at week 16. Conversely, dose-dependent laboratory abnormalities were observed with PF-06826647, including anemia, neutropenia, and increases in creatine phosphokinase.¹⁷ At high concentrations, PF-06826647 may disrupt JAK signaling pathways involved in hematopoiesis and renal functions owing to its mode of action as a competitive inhibitor. Overall, these agents are much farther from market, and long-term studies with larger diverse patient cohorts are required to adequately assess the efficacy and safety data of these novel oral TYK2 inhibitors for patients with psoriasis.

EDP1815—EDP1815 is an oral preparation of a single strain of Prevotella histicola being developed for the treatment of inflammatory diseases, including psoriasis. EDP1815 interacts with host intestinal immune cells through the small intestinal axis (SINTAX) to suppress systemic inflammation across the T_H1, T_H2, and T_H17 pathways. Therapy triggers broad immunomodulatory effects without causing systemic absorption, colonic colonization, or modification of the gut microbiome.¹⁸ In a phase 2 study (NCT04603027), the primary end point analysis, mean percentage change in PASI between treatment and placebo, demonstrated that at week 16, EDP1815 was superior to placebo with 80% to 90% probability across each cohort. At week 16, 25% to 32% of patients across the 3 cohorts treated with EDP1815 achieved PASI 50 compared with 12% of patients receiving placebo. Gastrointestinal AEs were comparable between treatment and placebo groups. These results suggest that SINTAX-targeted therapies may provide efficacious and safe immunomodulatory effects for patients with mild to moderate psoriasis, who often have limited treatment options. Although improvements may be mild, SINTAX-targeted therapies can be seen as a particularly attractive adjunctive treatment for patients with severe psoriasis taking other medications or as part of a treatment approach for a patient with milder psoriasis.

Biologics

Bimekizumab—Bimekizumab is a monoclonal IgG1 antibody that selectively inhibits IL-17A and IL-17F. Although IL-17A is a more potent cytokine, IL-17F may be more highly expressed in psoriatic lesional skin and independently contribute to the activation of proinflammatory signaling pathways implicated in the pathophysiology of psoriasis.¹⁹ Evidence suggests that dual inhibition of IL-17A and IL-17F may provide more complete suppression of inflammation and improved clinical responses than IL-17A inhibition alone.²⁰

Prior bimekizumab phase 3 clinical studies have shown both rapid and durable clinical improvements in skin clearance compared with placebo.²¹ Three phase 3 trials—BE VIVID (N=567),²² BE SURE (N=478),²³ and BE RADIANT (N=743)²⁴—assessed the efficacy and safety of bimekizumab vs the IL-12/IL-23 inhibitor ustekinumab, the tumor necrosis factor inhibitor adalimumab, and the selective IL-17A inhibitor secukinumab, respectively. At week 4, significantly more patients treated with bimekizumab (71%–77%) achieved PASI 75 than patients treated with ustekinumab (15%; P<.0001), adalimumab (31.4%; P<.001), or secukinumab (47.3%; P<.001).^22-24 After 16 weeks of treatment, PASI 90 was achieved by 85% to 86.2%, 50%, and 47.2% of patients treated with bimekizumab, ustekinumab, and adalimumab, respectively.^22,23 At week 16, PASI 100 was observed in 59% to 61.7%, 21%, 23.9%, and 48.9% of patients treated with bimekizumab, ustekinumab, adalimumab, and secukinumab, respectively. An IGA response (score of 0/1) at week 16 was achieved by 84% to 85.5%, 53%, 57.2%, and 78.6% of patients receiving bimekizumab, ustekinumab, adalimumab, and secukinumab, respectively.^22-24

The most common AEs in bimekizumab-treated patients were nasopharyngitis, oral candidiasis, and upper respiratory tract infection.^22-24 The dual inhibition of IL-17A and IL-17F suppresses host defenses against Candida at the oral mucosa, increasing the incidence of bimekizumab-associated oral candidiasis.²⁵ Despite the increased risk of Candida infections, these data suggest that inhibition of both IL-17A and IL-17F with bimekizumab may provide faster and greater clinical benefit for patients with moderate to severe plaque psoriasis than inhibition of IL-17A alone and other biologic therapies, as the PASI 100 clearance rates across the multiple comparator trials and the placebo-controlled pivotal trial are consistently the highest among any biologic for the treatment of psoriasis.

Spesolimab—The IL-36 pathway and IL-36 receptor genes have been linked to the pathogenesis of generalized pustular psoriasis.²⁶ In a phase 2 trial, 19 of 35 patients (54%) receiving an intravenous dose of spesolimab, an IL-36 receptor inhibitor, had a generalized pustular psoriasis PGA pustulation subscore of 0 (no visible pustules) at the end of week 1 vs 6% of patients in the placebo group.²⁷ A generalized pustular psoriasis PGA total score of 0 or 1 was observed in 43% (15/35) of spesolimab-treated patients compared with 11% (2/18) of patients in the placebo group. The most common AEs in patients treated with spesolimab were minor infections.²⁷ Two open-label phase 3 trials—NCT05200247 and NCT05239039—are underway to determine the long-term efficacy and safety of spesolimab in patients with generalized pustular psoriasis.

Conclusion

Although we have seen a renaissance in psoriasis therapies with the advent of biologics in the last 20 years, recent evidence shows that more innovation is underway. Just in the last year, 2 new mechanisms for treating psoriasis topically without steroids have come to fruition, and there have not been truly novel mechanisms for treating psoriasis topically since approvals for tazarotene and calcipotriene in the 1990s. An entirely new class—TYK2 inhibitors—was developed and landed in psoriasis first, greatly improving the efficacy measures attained with oral medications in general. Finally, an orphan diagnosis got its due with an ambitiously designed study looking at a previously unheard-of 1-week end point, but it comes for one of the few true dermatologic emergencies we encounter, generalized pustular psoriasis. We are fortunate to have so many meaningful new treatments available to us, and it is invigorating to see that even more efficacious biologics and treatments are coming, along with novel concepts such as a treatment affecting the microbiome. Now, we just need to make sure that our patients have the access they deserve to the wide array of available treatments.

A Mendelian randomization study employing data from nearly 300,000 individuals has linked elevated levels of the PCSK9 enzyme with an increased risk of psoriasis, suggesting it might be targetable as an intervention.

Independent of low-density lipoprotein cholesterol (LDL-C), which is reduced when PCSK9 is inhibited, a reduction in PCSK9 levels appears to have a direct impact on lowering psoriasis risk. Conversely, psoriasis risk did not appear to be affected when LDL-C was reduced by other pathways of lipid control.

petekarici/Getty Images

This study “suggests that PCSK9 inhibition is causally associated with reduced risk of psoriasis,” reported a team of investigators led by Sizheng Steven Zhao, MD, PhD, of the division of musculoskeletal and dermatological sciences, University of Manchester (England). “Existing PCSK9 inhibitors hold potential as therapeutic targets for prevention, and possibly treatment, of psoriasis, although further clinical studies are needed,” they concluded.

In an interview, Dr. Zhao also noted that it will be interesting to look at psoriasis susceptibility in post hoc analyses of large randomized controlled trials of PCSK9 inhibitors for cardiovascular disease.

“Genetically proxied” inhibition of HMG-CoA reductase, which is targeted by statins, and NPC1L1 which is targeted by ezetimibe, “were not associated with psoriasis risk,” the investigators reported in the study, published in JAMA Dermatology.

Abnormal lipid metabolism is sufficiently common among people with psoriasis that screening in patients with moderate to severe disease is recommended in 2019 psoriasis guidelines from the American Academy of Dermatology and the National Psoriasis Foundation. However, the link between these diseases is unclear. This study was launched to explore genetically proxied relationships between psoriasis and LDL-C reductions as well as specific treatments for elevated LDL-C.

Mendelian randomizations were applied to deidentified data from two sources, a UK biobank and FinnGen, a Finnish-based project for identifying genotype-to-phenotype correlations. Genetic proxies for these variables were established on the basis of genomewide association studies on large population samples.

Ultimately, 34 genetic variants were selected to proxy for lipid lowering by PCSK9, 19 were selected to proxy for HMG-CoA reductase, and 9 for NPC1L1. In the Mendelian analyses performed on the two sources, genetically proxied PCSK9 inhibition was associated with about a 30% reduction in the odds ratio of psoriasis (OR, 0.69; P = .003). There were no robust associations with proxies for reductions in either HMG-CoA reductase or NPC1L1.

In sensitivity analyses, there was no evidence of bias from pleiotropy or genetic confounding, according to Dr. Zhao and his coauthors, who noted that the relationship between reductions in PCSK9 and reduced risk of psoriasis appeared to be independent of change in circulating LDL-C.

Given the prior evidence implicating the PCSK9 enzyme in psoriasis risk, “this is an exciting study that really highlights the importance of studying and targeting lipid metabolism in psoriasis for a few reasons,” according to Michael S. Garshick, MD, a researcher, cardiologist, and director of the cardio-rheumatology program, New York University Langone Health.

An investigator who has participated in several studies evaluating the relationship between cardiovascular risk and psoriasis, Dr. Garshick said there is increasing interest in PCSK9 as a biomarker or even a mediator of inflammation independent of blood lipid levels.

“In psoriasis regarding PCSK9, we and others have shown PCSK9 is elevated in psoriatic lesion skin, and studies are starting to investigate the unique lipidomic profile in psoriasis,” Dr. Garshick said in an interview. The study he led that showed elevated PCSK9 levels in psoriatic skin was published in 2021 in the Journal of Investigative Dermatology.

While the Mendelian randomization provides only “an inference” that PCSK9 plays a role in mediating risk of psoriasis, Dr. Zhao and coauthors cited numerous studies linking elevated PCSK9 to psoriasis pathophysiology. This not only includes the elevated PCSK9 expression in psoriatic plaques as shown by Dr. Garshick and others but several sets of experimental evidence linking PCSK9 to inflammatory pathways, including upregulation of interleukin-17 and stimulation of macrophage activation.

While Dr. Zhao and coauthors suggested that clinical trials are now needed to test the potential of PCSK9 inhibitors to modify the risk of psoriasis, Dr. Garshick indicated that there are numerous variables to unravel in the relationship between elevated lipids, PCSK9, and psoriasis.

“In our own studies, we did see a statistical correlation between circulating PCSK9 and psoriasis severity,” Dr. Garshick said. But he added, “I think we are just beginning to understand the functions of circulating (extrahepatic) PCSK9 independent of lipid metabolism.”

While he is intrigued by the evidence that PCSK9 is linked to systemic inflammation, he pointed out that several medications used to treat dyslipidemias, such as statins, are associated with an anti-inflammatory effect.

This study “further emphasizes the need to conduct clinical trials treating dyslipidemia in psoriasis, including the targeting of PCSK9, whether it is with statins with lipid lowering and potential pleiotropic anti-inflammatory properties or PCSK9 inhibition,” he said. If positive, “both would be exciting.“

From a cardiologist’s point of view, there is an upside for including patients with psoriasis in lipid-lowering trials even if the effect on psoriasis is modest. Either way, “you still get the lipid-lowering benefit, which is important for reducing atherosclerotic cardiovascular disease,” Dr. Garshick said.

Dr. Zhao reported financial relationships with UCB, although UCB did not provide funding for this study. One author reported grants from Versus Arthritis and the National Institute for Health Research Manchester Biomedical Research Centre during the study, grants from Bristol Myers Squibb, Galapagos, and Pfizer, and personal fees from Chugai Roche outside the submitted work. No other disclosures were reported. The study was supported by grants from Versus Arthritis and the NIHR Manchester Biomedical Research Centre. Dr. Garshick reported financial relationships with AbbVie and Horizon Therapeutics.

A Mendelian randomization study employing data from nearly 300,000 individuals has linked elevated levels of the PCSK9 enzyme with an increased risk of psoriasis, suggesting it might be targetable as an intervention.

Independent of low-density lipoprotein cholesterol (LDL-C), which is reduced when PCSK9 is inhibited, a reduction in PCSK9 levels appears to have a direct impact on lowering psoriasis risk. Conversely, psoriasis risk did not appear to be affected when LDL-C was reduced by other pathways of lipid control.

petekarici/Getty Images

This study “suggests that PCSK9 inhibition is causally associated with reduced risk of psoriasis,” reported a team of investigators led by Sizheng Steven Zhao, MD, PhD, of the division of musculoskeletal and dermatological sciences, University of Manchester (England). “Existing PCSK9 inhibitors hold potential as therapeutic targets for prevention, and possibly treatment, of psoriasis, although further clinical studies are needed,” they concluded.

In an interview, Dr. Zhao also noted that it will be interesting to look at psoriasis susceptibility in post hoc analyses of large randomized controlled trials of PCSK9 inhibitors for cardiovascular disease.

“Genetically proxied” inhibition of HMG-CoA reductase, which is targeted by statins, and NPC1L1 which is targeted by ezetimibe, “were not associated with psoriasis risk,” the investigators reported in the study, published in JAMA Dermatology.

Abnormal lipid metabolism is sufficiently common among people with psoriasis that screening in patients with moderate to severe disease is recommended in 2019 psoriasis guidelines from the American Academy of Dermatology and the National Psoriasis Foundation. However, the link between these diseases is unclear. This study was launched to explore genetically proxied relationships between psoriasis and LDL-C reductions as well as specific treatments for elevated LDL-C.

Mendelian randomizations were applied to deidentified data from two sources, a UK biobank and FinnGen, a Finnish-based project for identifying genotype-to-phenotype correlations. Genetic proxies for these variables were established on the basis of genomewide association studies on large population samples.

Ultimately, 34 genetic variants were selected to proxy for lipid lowering by PCSK9, 19 were selected to proxy for HMG-CoA reductase, and 9 for NPC1L1. In the Mendelian analyses performed on the two sources, genetically proxied PCSK9 inhibition was associated with about a 30% reduction in the odds ratio of psoriasis (OR, 0.69; P = .003). There were no robust associations with proxies for reductions in either HMG-CoA reductase or NPC1L1.

In sensitivity analyses, there was no evidence of bias from pleiotropy or genetic confounding, according to Dr. Zhao and his coauthors, who noted that the relationship between reductions in PCSK9 and reduced risk of psoriasis appeared to be independent of change in circulating LDL-C.

Given the prior evidence implicating the PCSK9 enzyme in psoriasis risk, “this is an exciting study that really highlights the importance of studying and targeting lipid metabolism in psoriasis for a few reasons,” according to Michael S. Garshick, MD, a researcher, cardiologist, and director of the cardio-rheumatology program, New York University Langone Health.

An investigator who has participated in several studies evaluating the relationship between cardiovascular risk and psoriasis, Dr. Garshick said there is increasing interest in PCSK9 as a biomarker or even a mediator of inflammation independent of blood lipid levels.

“In psoriasis regarding PCSK9, we and others have shown PCSK9 is elevated in psoriatic lesion skin, and studies are starting to investigate the unique lipidomic profile in psoriasis,” Dr. Garshick said in an interview. The study he led that showed elevated PCSK9 levels in psoriatic skin was published in 2021 in the Journal of Investigative Dermatology.

While the Mendelian randomization provides only “an inference” that PCSK9 plays a role in mediating risk of psoriasis, Dr. Zhao and coauthors cited numerous studies linking elevated PCSK9 to psoriasis pathophysiology. This not only includes the elevated PCSK9 expression in psoriatic plaques as shown by Dr. Garshick and others but several sets of experimental evidence linking PCSK9 to inflammatory pathways, including upregulation of interleukin-17 and stimulation of macrophage activation.

While Dr. Zhao and coauthors suggested that clinical trials are now needed to test the potential of PCSK9 inhibitors to modify the risk of psoriasis, Dr. Garshick indicated that there are numerous variables to unravel in the relationship between elevated lipids, PCSK9, and psoriasis.

“In our own studies, we did see a statistical correlation between circulating PCSK9 and psoriasis severity,” Dr. Garshick said. But he added, “I think we are just beginning to understand the functions of circulating (extrahepatic) PCSK9 independent of lipid metabolism.”

While he is intrigued by the evidence that PCSK9 is linked to systemic inflammation, he pointed out that several medications used to treat dyslipidemias, such as statins, are associated with an anti-inflammatory effect.

This study “further emphasizes the need to conduct clinical trials treating dyslipidemia in psoriasis, including the targeting of PCSK9, whether it is with statins with lipid lowering and potential pleiotropic anti-inflammatory properties or PCSK9 inhibition,” he said. If positive, “both would be exciting.“

From a cardiologist’s point of view, there is an upside for including patients with psoriasis in lipid-lowering trials even if the effect on psoriasis is modest. Either way, “you still get the lipid-lowering benefit, which is important for reducing atherosclerotic cardiovascular disease,” Dr. Garshick said.

Dr. Zhao reported financial relationships with UCB, although UCB did not provide funding for this study. One author reported grants from Versus Arthritis and the National Institute for Health Research Manchester Biomedical Research Centre during the study, grants from Bristol Myers Squibb, Galapagos, and Pfizer, and personal fees from Chugai Roche outside the submitted work. No other disclosures were reported. The study was supported by grants from Versus Arthritis and the NIHR Manchester Biomedical Research Centre. Dr. Garshick reported financial relationships with AbbVie and Horizon Therapeutics.

A Mendelian randomization study employing data from nearly 300,000 individuals has linked elevated levels of the PCSK9 enzyme with an increased risk of psoriasis, suggesting it might be targetable as an intervention.

Independent of low-density lipoprotein cholesterol (LDL-C), which is reduced when PCSK9 is inhibited, a reduction in PCSK9 levels appears to have a direct impact on lowering psoriasis risk. Conversely, psoriasis risk did not appear to be affected when LDL-C was reduced by other pathways of lipid control.

petekarici/Getty Images

This study “suggests that PCSK9 inhibition is causally associated with reduced risk of psoriasis,” reported a team of investigators led by Sizheng Steven Zhao, MD, PhD, of the division of musculoskeletal and dermatological sciences, University of Manchester (England). “Existing PCSK9 inhibitors hold potential as therapeutic targets for prevention, and possibly treatment, of psoriasis, although further clinical studies are needed,” they concluded.

In an interview, Dr. Zhao also noted that it will be interesting to look at psoriasis susceptibility in post hoc analyses of large randomized controlled trials of PCSK9 inhibitors for cardiovascular disease.

“Genetically proxied” inhibition of HMG-CoA reductase, which is targeted by statins, and NPC1L1 which is targeted by ezetimibe, “were not associated with psoriasis risk,” the investigators reported in the study, published in JAMA Dermatology.

Abnormal lipid metabolism is sufficiently common among people with psoriasis that screening in patients with moderate to severe disease is recommended in 2019 psoriasis guidelines from the American Academy of Dermatology and the National Psoriasis Foundation. However, the link between these diseases is unclear. This study was launched to explore genetically proxied relationships between psoriasis and LDL-C reductions as well as specific treatments for elevated LDL-C.

Mendelian randomizations were applied to deidentified data from two sources, a UK biobank and FinnGen, a Finnish-based project for identifying genotype-to-phenotype correlations. Genetic proxies for these variables were established on the basis of genomewide association studies on large population samples.

Ultimately, 34 genetic variants were selected to proxy for lipid lowering by PCSK9, 19 were selected to proxy for HMG-CoA reductase, and 9 for NPC1L1. In the Mendelian analyses performed on the two sources, genetically proxied PCSK9 inhibition was associated with about a 30% reduction in the odds ratio of psoriasis (OR, 0.69; P = .003). There were no robust associations with proxies for reductions in either HMG-CoA reductase or NPC1L1.

In sensitivity analyses, there was no evidence of bias from pleiotropy or genetic confounding, according to Dr. Zhao and his coauthors, who noted that the relationship between reductions in PCSK9 and reduced risk of psoriasis appeared to be independent of change in circulating LDL-C.

Given the prior evidence implicating the PCSK9 enzyme in psoriasis risk, “this is an exciting study that really highlights the importance of studying and targeting lipid metabolism in psoriasis for a few reasons,” according to Michael S. Garshick, MD, a researcher, cardiologist, and director of the cardio-rheumatology program, New York University Langone Health.

An investigator who has participated in several studies evaluating the relationship between cardiovascular risk and psoriasis, Dr. Garshick said there is increasing interest in PCSK9 as a biomarker or even a mediator of inflammation independent of blood lipid levels.

“In psoriasis regarding PCSK9, we and others have shown PCSK9 is elevated in psoriatic lesion skin, and studies are starting to investigate the unique lipidomic profile in psoriasis,” Dr. Garshick said in an interview. The study he led that showed elevated PCSK9 levels in psoriatic skin was published in 2021 in the Journal of Investigative Dermatology.

While the Mendelian randomization provides only “an inference” that PCSK9 plays a role in mediating risk of psoriasis, Dr. Zhao and coauthors cited numerous studies linking elevated PCSK9 to psoriasis pathophysiology. This not only includes the elevated PCSK9 expression in psoriatic plaques as shown by Dr. Garshick and others but several sets of experimental evidence linking PCSK9 to inflammatory pathways, including upregulation of interleukin-17 and stimulation of macrophage activation.

While Dr. Zhao and coauthors suggested that clinical trials are now needed to test the potential of PCSK9 inhibitors to modify the risk of psoriasis, Dr. Garshick indicated that there are numerous variables to unravel in the relationship between elevated lipids, PCSK9, and psoriasis.

“In our own studies, we did see a statistical correlation between circulating PCSK9 and psoriasis severity,” Dr. Garshick said. But he added, “I think we are just beginning to understand the functions of circulating (extrahepatic) PCSK9 independent of lipid metabolism.”

While he is intrigued by the evidence that PCSK9 is linked to systemic inflammation, he pointed out that several medications used to treat dyslipidemias, such as statins, are associated with an anti-inflammatory effect.

This study “further emphasizes the need to conduct clinical trials treating dyslipidemia in psoriasis, including the targeting of PCSK9, whether it is with statins with lipid lowering and potential pleiotropic anti-inflammatory properties or PCSK9 inhibition,” he said. If positive, “both would be exciting.“

From a cardiologist’s point of view, there is an upside for including patients with psoriasis in lipid-lowering trials even if the effect on psoriasis is modest. Either way, “you still get the lipid-lowering benefit, which is important for reducing atherosclerotic cardiovascular disease,” Dr. Garshick said.

Dr. Zhao reported financial relationships with UCB, although UCB did not provide funding for this study. One author reported grants from Versus Arthritis and the National Institute for Health Research Manchester Biomedical Research Centre during the study, grants from Bristol Myers Squibb, Galapagos, and Pfizer, and personal fees from Chugai Roche outside the submitted work. No other disclosures were reported. The study was supported by grants from Versus Arthritis and the NIHR Manchester Biomedical Research Centre. Dr. Garshick reported financial relationships with AbbVie and Horizon Therapeutics.

Fluorescence-optical imaging (FOI) identified early signs of psoriatic arthritis, based on data from 2 years of follow-up of a cohort of 389 adults at 14 rheumatology centers.

Approximately 25% of individuals with psoriasis go on to develop psoriatic arthritis (PsA), but there are no validated biomarkers to identify patients at risk for progression to PsA, Michaela Koehm, MD, of Goethe University, Frankfurt am Main, Germany, and colleagues wrote in RMD Open.

FOI is a technique that allows assessment of changes in microvascularization and subdermal skin inflammation, and because individuals with psoriasis who develop PsA have shown changes in blood vessel formation in the early stages of disease, the researchers sought to determine if FOI could be used to predict early PsA.

The researchers conducted a multicenter, two-part observational cohort study. The two parts, known as XCITING and XTEND, included 389 adults aged 18-75 years with plaque psoriasis deemed at increased risk for PsA. The patients were seen at rheumatology sites in Germany between Jan. 28, 2014, and March 16, 2017. The XTEND study included clinic visits 18-24 months after the XCITING study.

Participants underwent a complete clinical examination, with musculoskeletal ultrasound (MSUS) and FOI on both hands at a single visit. Those with positive FOI findings not seen with clinical exam or MSUS underwent MRI within 7 days. Patients with positive FOI but negative findings on clinical exam, MSUS, and MRI were followed for 2 years in the XTEND study.

The primary outcome was the ability of FOI to detect musculoskeletal inflammation, compared with clinical examination and MSUS.

Overall, 50% of the patients were diagnosed with PsA. A total of 116 (30%) had positive FOI findings; complete MRI data were available for 108 of these patients, including 68 negative MRIs and 40 positive MRIs.

In the XTEND study, another 12% of patients who were positive on FOI but not on MRI also developed PsA by the end of the 2-year follow-up. In comparison, the researchers noted that “literature data on yearly incidence rates [of PsA] in different national cohorts indicate an incidence rate of approximately 4.3% per year.”

A total of 149 of the 196 patients with PsA confirmed by either clinical exam or MSUS were also positive on FOI, yielding a sensitivity of 76.0%. The specificity of FOI was 39.5%.

The sensitive visualization of musculoskeletal inflammation possible with FOI “may exceed its ability to detect clinically manifest PsA at high sensitivity or specificity, but early visualization is arguably of greater value as other imaging methods are currently available for detection of later stages of PsA,” the researchers wrote in their discussion. “A technique allowing early identification of PsA may be especially valuable for nonrheumatologists, including dermatologists and general practitioners, and help expedite more efficient referral to specialists.”

The findings were limited by several factors, including the nonrandomized design and small subgroup numbers, the researchers noted. Other limitations include the presence of alternative conditions such as osteoarthritis that might have complicated the imaging; the focus only on the hands; and potential variation in FOI assessment related to technical standards such as temperature and positioning.

However, the results support FOI as a safe and effective method of detecting early signs of joint inflammation that could predict increased risk for PsA in psoriasis patients, the researchers said.

The researchers added that more work is needed to evaluate FOI in clinical practice, but FOI has the potential to identify vascularization changes earlier than other imaging modalities and in advance of clinical symptoms.

“Accordingly, FOI may have the potential to improve patient outcomes in PsA by reducing the time to initiation of early treatment,” they concluded.

The study was supported by Fraunhofer ITMP, a nonprofit organization, and a research grant from Pfizer Germany. Some of the researchers disclosed financial relationships with many pharmaceutical companies, including Pfizer.

Fluorescence-optical imaging (FOI) identified early signs of psoriatic arthritis, based on data from 2 years of follow-up of a cohort of 389 adults at 14 rheumatology centers.

Approximately 25% of individuals with psoriasis go on to develop psoriatic arthritis (PsA), but there are no validated biomarkers to identify patients at risk for progression to PsA, Michaela Koehm, MD, of Goethe University, Frankfurt am Main, Germany, and colleagues wrote in RMD Open.

FOI is a technique that allows assessment of changes in microvascularization and subdermal skin inflammation, and because individuals with psoriasis who develop PsA have shown changes in blood vessel formation in the early stages of disease, the researchers sought to determine if FOI could be used to predict early PsA.

The researchers conducted a multicenter, two-part observational cohort study. The two parts, known as XCITING and XTEND, included 389 adults aged 18-75 years with plaque psoriasis deemed at increased risk for PsA. The patients were seen at rheumatology sites in Germany between Jan. 28, 2014, and March 16, 2017. The XTEND study included clinic visits 18-24 months after the XCITING study.

Participants underwent a complete clinical examination, with musculoskeletal ultrasound (MSUS) and FOI on both hands at a single visit. Those with positive FOI findings not seen with clinical exam or MSUS underwent MRI within 7 days. Patients with positive FOI but negative findings on clinical exam, MSUS, and MRI were followed for 2 years in the XTEND study.

The primary outcome was the ability of FOI to detect musculoskeletal inflammation, compared with clinical examination and MSUS.

Overall, 50% of the patients were diagnosed with PsA. A total of 116 (30%) had positive FOI findings; complete MRI data were available for 108 of these patients, including 68 negative MRIs and 40 positive MRIs.

In the XTEND study, another 12% of patients who were positive on FOI but not on MRI also developed PsA by the end of the 2-year follow-up. In comparison, the researchers noted that “literature data on yearly incidence rates [of PsA] in different national cohorts indicate an incidence rate of approximately 4.3% per year.”

A total of 149 of the 196 patients with PsA confirmed by either clinical exam or MSUS were also positive on FOI, yielding a sensitivity of 76.0%. The specificity of FOI was 39.5%.

The sensitive visualization of musculoskeletal inflammation possible with FOI “may exceed its ability to detect clinically manifest PsA at high sensitivity or specificity, but early visualization is arguably of greater value as other imaging methods are currently available for detection of later stages of PsA,” the researchers wrote in their discussion. “A technique allowing early identification of PsA may be especially valuable for nonrheumatologists, including dermatologists and general practitioners, and help expedite more efficient referral to specialists.”

The findings were limited by several factors, including the nonrandomized design and small subgroup numbers, the researchers noted. Other limitations include the presence of alternative conditions such as osteoarthritis that might have complicated the imaging; the focus only on the hands; and potential variation in FOI assessment related to technical standards such as temperature and positioning.

However, the results support FOI as a safe and effective method of detecting early signs of joint inflammation that could predict increased risk for PsA in psoriasis patients, the researchers said.

The researchers added that more work is needed to evaluate FOI in clinical practice, but FOI has the potential to identify vascularization changes earlier than other imaging modalities and in advance of clinical symptoms.

“Accordingly, FOI may have the potential to improve patient outcomes in PsA by reducing the time to initiation of early treatment,” they concluded.

The study was supported by Fraunhofer ITMP, a nonprofit organization, and a research grant from Pfizer Germany. Some of the researchers disclosed financial relationships with many pharmaceutical companies, including Pfizer.

Fluorescence-optical imaging (FOI) identified early signs of psoriatic arthritis, based on data from 2 years of follow-up of a cohort of 389 adults at 14 rheumatology centers.

Approximately 25% of individuals with psoriasis go on to develop psoriatic arthritis (PsA), but there are no validated biomarkers to identify patients at risk for progression to PsA, Michaela Koehm, MD, of Goethe University, Frankfurt am Main, Germany, and colleagues wrote in RMD Open.

FOI is a technique that allows assessment of changes in microvascularization and subdermal skin inflammation, and because individuals with psoriasis who develop PsA have shown changes in blood vessel formation in the early stages of disease, the researchers sought to determine if FOI could be used to predict early PsA.

The researchers conducted a multicenter, two-part observational cohort study. The two parts, known as XCITING and XTEND, included 389 adults aged 18-75 years with plaque psoriasis deemed at increased risk for PsA. The patients were seen at rheumatology sites in Germany between Jan. 28, 2014, and March 16, 2017. The XTEND study included clinic visits 18-24 months after the XCITING study.

Participants underwent a complete clinical examination, with musculoskeletal ultrasound (MSUS) and FOI on both hands at a single visit. Those with positive FOI findings not seen with clinical exam or MSUS underwent MRI within 7 days. Patients with positive FOI but negative findings on clinical exam, MSUS, and MRI were followed for 2 years in the XTEND study.

The primary outcome was the ability of FOI to detect musculoskeletal inflammation, compared with clinical examination and MSUS.

Overall, 50% of the patients were diagnosed with PsA. A total of 116 (30%) had positive FOI findings; complete MRI data were available for 108 of these patients, including 68 negative MRIs and 40 positive MRIs.

In the XTEND study, another 12% of patients who were positive on FOI but not on MRI also developed PsA by the end of the 2-year follow-up. In comparison, the researchers noted that “literature data on yearly incidence rates [of PsA] in different national cohorts indicate an incidence rate of approximately 4.3% per year.”

A total of 149 of the 196 patients with PsA confirmed by either clinical exam or MSUS were also positive on FOI, yielding a sensitivity of 76.0%. The specificity of FOI was 39.5%.

The sensitive visualization of musculoskeletal inflammation possible with FOI “may exceed its ability to detect clinically manifest PsA at high sensitivity or specificity, but early visualization is arguably of greater value as other imaging methods are currently available for detection of later stages of PsA,” the researchers wrote in their discussion. “A technique allowing early identification of PsA may be especially valuable for nonrheumatologists, including dermatologists and general practitioners, and help expedite more efficient referral to specialists.”

The findings were limited by several factors, including the nonrandomized design and small subgroup numbers, the researchers noted. Other limitations include the presence of alternative conditions such as osteoarthritis that might have complicated the imaging; the focus only on the hands; and potential variation in FOI assessment related to technical standards such as temperature and positioning.

However, the results support FOI as a safe and effective method of detecting early signs of joint inflammation that could predict increased risk for PsA in psoriasis patients, the researchers said.

The researchers added that more work is needed to evaluate FOI in clinical practice, but FOI has the potential to identify vascularization changes earlier than other imaging modalities and in advance of clinical symptoms.

“Accordingly, FOI may have the potential to improve patient outcomes in PsA by reducing the time to initiation of early treatment,” they concluded.

The study was supported by Fraunhofer ITMP, a nonprofit organization, and a research grant from Pfizer Germany. Some of the researchers disclosed financial relationships with many pharmaceutical companies, including Pfizer.

If you could go back in time 75 years and tell Dr. Sidney Farber, the developer of methotrexate for cancer therapy, that 21st-century medicine would utilize his specially designed drug more in rheumatology than oncology, he might be surprised. He might scratch his head even more, hearing of his drug sparking interest in still other medical fields, like cardiology.

But drug repurposing is not so uncommon. One classic example is aspirin. Once the most common pain medication and used also in rheumatology, aspirin now finds a range of applications, from colorectal cancer to the prevention of cardiovascular and cerebrovascular thrombosis. Minoxidil is another example, developed for hypertension but used today mostly to stop hair loss. Perhaps most ironic is thalidomide, utilized today for leprosy and multiple myeloma, yet actually contraindicated for its original application, nausea of pregnancy.

Courtesy NIH

Methotrexate, thus, has much in common with other medical treatments, and yet its origin story is as unique and as fascinating as the story of Dr. Farber himself. While this is a rheumatology article, it’s also a story about the origin of a particular rheumatologic treatment, and so the story of that origin will take us mostly through a discussion of hematologic malignancy and of the clinical researcher who dared search for a cure.

Born in 1903, in Buffalo, New York, third of fourteen children of Jewish immigrants from Poland, Dr. Farber grew up in a household that was crowded but academically rigorous. His father, Simon, routinely brought home textbooks, assigning each child a book to read and on which to write a report. His mother, Matilda, was as devoted as her husband to raising the children to succeed in their adopted new country. Upstairs, the children were permitted to speak Yiddish, but downstairs they were required to use only English and German.

As a teen, Dr. Farber lived through the 1918 influenza pandemic that killed at least 50 million people worldwide, including more than 2,000 Buffalonians. This probably helped motivate him to study medicine, but with antisemitism overt in the America of the early 1920s, securing admission to a U.S. medical school was close to impossible. So, in what now seems like the greatest of ironies, Dr. Farber began medical studies in Germany, then transferred for the second year to a U.S. program that seemed adequate – Harvard Medical School, from which he graduated in 1927. From there, he trained as a pathologist, focusing ultimately on pediatric pathology. But, frustrated by case after case of malignancy, whose young victims he’d often have to autopsy, Dr. Farber decided that he wanted to advance the pitiful state of cancer therapeutics, especially for hematologic malignancy.

This was a tall order in the 1930s and early 1940s, when cancer therapeutics consisted only of surgical resection and very primitive forms of radiation therapy. Applicable only to neoplasia that was localized, these options were useless against malignancies in the blood, like acute lymphoblastic leukemia (ALL), but by January 1948 there was at least one glimmer of hope. At that time, one patient with ALL, 2-year-old Robert Sandler, was too ill to join his twin brother Elliott for snow play outside their home in the Dorchester section of Boston. Diagnosed back in August, Robert had suffered multiple episodes of fever, anemia, and thrombocytopenia. His illness had enlarged his spleen dramatically and caused pathologic bone fractures with excruciating bone pain, and for a while he couldn’t walk because of pressure on his lower spinal cord. All of this was the result of uncontrolled mitosis and cell division of lymphoblasts, immature lymphocytes. By December, these out-of-control cells had elevated the boy’s white blood cell count to a peak of 70,000/mcL, more than six times the high end of the normal range (4,500-11,000/mcL). This had happened despite treatment with an experimental drug, developed at Boston Children’s Hospital by Dr. Farber and his team, working on the assumption that inhibition of folate metabolism should slow the growth of tumor cells. On Dec. 28, however, Dr. Farber had switched the child to a new drug with a chemical structure just slightly different from the other agent’s.

Merely another chemical modification in a series of attempts by the research team, the new drug, aminopterin, was not expected to do anything dramatic, but Dr. Farber and the team had come such a long way since the middle of 1947, when he’d actually done the opposite of what he was doing now. On the basis of British research from India showing folic acid deficiency as the basis of a common type of anemia in malnourished people, Dr. Farber had reasoned that children with leukemia, who also suffered from anemia, might also benefit from folic acid supplementation. Even without prior rodent testing, Dr. Farber had tried giving the nutrient to patients with ALL, a strategy made possible by the presence of a spectacular chemist working on folic acid synthesis at Farber’s own hospital to help combat folate deficiency. Born into a poor Brahmin family in India, the chemist, Dr. Yellapragada SubbaRow, had begun life with so much stacked against him as to appear even less likely during childhood than the young Dr. Farber to grow up to make major contributions to medicine. Going through childhood with death all around him, Dr. SubbaRow was motivated to study medicine, but getting into medical school had been an uphill fight, given his family’s economic difficulty. Knowing that he’d also face discrimination on account of his low status after receiving admission to a medical program, SubbaRow could have made things a bit easier for himself by living within the norms of the British Imperial system, but as a supporter of Mohandas Gandhi’s nationalist movement, he boycotted British goods. As a medical student, this meant doing things like wearing Indian-made surgical gloves, instead of the English products that were expected of the students. Such actions led Dr. SubbaRow to receive a kind of second-rate medical degree, rather than the prestigious MBBS.

The political situation also led Dr. SubbaRow to emigrate to the United States, where, ironically, his medical degree initially was taken less seriously than it had been taken in his British-occupied homeland. He thus worked in the capacity of a hospital night porter at Peter Bent Brigham Hospital (the future Brigham and Women’s Hospital), doing menial tasks like changing sheets to make ends meet. He studied, however, and made enough of an impression to gain admission to the same institution that also admitted Farber through the backdoor, Harvard Medical School. This launched him into a research career in which he not only would be instrumental in developing folate antagonists and other classes of drugs, but also would make him the codiscoverer of the role of creatine phosphate and ATP in cellular energy metabolism. Sadly, even after obtaining his top-notch American credentials and contributing through his research to what you might say is a good chunk of the biochemistry pathways that first year medical students memorize without ever learning who discovered them, Dr. SubbaRow still faced prejudice for the rest of his life, which turned out to last only until the age of 53. To add insult to injury, he is rarely remembered for his role.

Dr. Farber proceeded with the folic acid supplementation idea in patients with ALL, even though ALL caused a hypoproliferative anemia, whereas anemia from folate deficiency was megaloblastic, meaning that erythrocytes were produced but they were oversized and dysfunctional. Tragically, folic acid had accelerated the disease process in children with ALL, but the process of chemical experimentation aimed at synthesizing folate also produced some compounds that mimicked chemical precursors of folate in a way that made them antifolates, inhibitors of folate metabolism. If folic acid made lymphoblasts grow faster, Dr. Farber had reasoned that antifolates should inhibit their growth. He thus asked the chemistry lab to focus on folate inhibitors. Testing aminopterin, beginning with young Robert Sandler at the end of December, is what proved his hypothesis correct. By late January, aminopterin had brought the child’s WBC count down to the realm of 12,000, just slightly above normal, with symptoms and signs abating as well, and by February, the child could play with his twin brother. It was not a cure; malignant lymphoblasts still showed on microscopy of Robert’s blood. While he and some 15 other children whom Dr. Farber treated in this early trial would all succumb to ALL, they experienced remission lasting several months.

This was a big deal because the concept of chemotherapy was based only on serendipitous observations of WBC counts dropping in soldiers exposed to nitrogen mustard gas during World War I and during an incident in World War II, yet aminopterin had been designed from the ground up. Though difficult to synthesize in quantities, there was no reason for Dr. Farber’s team not to keep tweaking the drug, and so they did. Replacing one hydrogen atom with a methyl group, they turned it into methotrexate.

Proving easier to synthesize and less toxic, methotrexate would become a workhorse for chemotherapy over the next couple of decades, but the capability of both methotrexate and aminopterin to blunt the growth of white blood cells and other cells did not go unnoticed outside the realm of oncology. As early as the 1950s, dermatologists were using aminopterin to treat psoriasis. This led to the approval of methotrexate for psoriasis in 1972.

Meanwhile, like oncology, infectious diseases, aviation medicine, and so many other areas of practice, rheumatology had gotten a major boost from research stemming from World War II. During the war, Dr. Philip Hench of the Mayo Clinic developed cortisone, which pilots used to stay alert and energetic during trans-Atlantic flights. But it turned out that cortisone had a powerful immunosuppressive effect that dramatically improved rheumatoid arthritis, leading Dr. Hench to receive the Nobel Prize in Physiology or Medicine in 1950. By the end of the 1950s, however, the significant side effects of long-term corticosteroid therapy were very clear, so over the next few decades there was a major effort to develop different treatments for RA and other rheumatologic diseases.

Top on the list of such agents was methotrexate, developed for RA in part by Dr. Michael Weinblatt of Brigham and Women’s Hospital in Boston. In the 1980s, Dr. Weinblatt published the first clinical trial showing the benefits of methotrexate for RA patients. This has since developed into a standard treatment, noticeably different from the original malignancy application in that it is a low-dose regimen. Patients taking methotrexate for RA typically receive no more than 25 mg per week orally, and often much less. Rheumatology today includes expertise in keeping long-term methotrexate therapy safe by monitoring liver function and through other routine tests. The routine nature of the therapy has brought methotrexate to the point of beckoning in a realm that Dr. Farber might not have predicted in his wildest imagination: cardiology. This is on account of the growing appreciation of the inflammatory process in the pathophysiology of atherosclerotic heart disease.

Meanwhile, being an antimetabolite, harmful to rapidly dividing cells, the danger of methotrexate to the embryo and fetus was recognized early. This made methotrexate off-limits to pregnant women, yet it also has made the drug useful as an abortifacient. Though not as good for medication abortion in unwanted but thriving pregnancies, where mifepristone/misoprostol has become the regimen of choice, methotrexate has become a workhorse in other obstetrical settings, such as for ending ectopic pregnancy.

Looking at the present and into the future, the potential for this very old medication looks wide open, as if it could go in any direction, so let’s wind up the discussion with the thought that we may be in for some surprises. Rather than jumping deeply into any rheumatologic issue, we spent most of this article weaving through other medical issues, but does this not make today’s story fairly analogous to rheumatology itself?

Dr. Warmflash is a physician from Portland, Ore. He reported no conflicts of interest.

This story was updated 2/10/2023.

A version of this article first appeared on Medscape.com.

If you could go back in time 75 years and tell Dr. Sidney Farber, the developer of methotrexate for cancer therapy, that 21st-century medicine would utilize his specially designed drug more in rheumatology than oncology, he might be surprised. He might scratch his head even more, hearing of his drug sparking interest in still other medical fields, like cardiology.

But drug repurposing is not so uncommon. One classic example is aspirin. Once the most common pain medication and used also in rheumatology, aspirin now finds a range of applications, from colorectal cancer to the prevention of cardiovascular and cerebrovascular thrombosis. Minoxidil is another example, developed for hypertension but used today mostly to stop hair loss. Perhaps most ironic is thalidomide, utilized today for leprosy and multiple myeloma, yet actually contraindicated for its original application, nausea of pregnancy.

Courtesy NIH

Methotrexate, thus, has much in common with other medical treatments, and yet its origin story is as unique and as fascinating as the story of Dr. Farber himself. While this is a rheumatology article, it’s also a story about the origin of a particular rheumatologic treatment, and so the story of that origin will take us mostly through a discussion of hematologic malignancy and of the clinical researcher who dared search for a cure.

Born in 1903, in Buffalo, New York, third of fourteen children of Jewish immigrants from Poland, Dr. Farber grew up in a household that was crowded but academically rigorous. His father, Simon, routinely brought home textbooks, assigning each child a book to read and on which to write a report. His mother, Matilda, was as devoted as her husband to raising the children to succeed in their adopted new country. Upstairs, the children were permitted to speak Yiddish, but downstairs they were required to use only English and German.

As a teen, Dr. Farber lived through the 1918 influenza pandemic that killed at least 50 million people worldwide, including more than 2,000 Buffalonians. This probably helped motivate him to study medicine, but with antisemitism overt in the America of the early 1920s, securing admission to a U.S. medical school was close to impossible. So, in what now seems like the greatest of ironies, Dr. Farber began medical studies in Germany, then transferred for the second year to a U.S. program that seemed adequate – Harvard Medical School, from which he graduated in 1927. From there, he trained as a pathologist, focusing ultimately on pediatric pathology. But, frustrated by case after case of malignancy, whose young victims he’d often have to autopsy, Dr. Farber decided that he wanted to advance the pitiful state of cancer therapeutics, especially for hematologic malignancy.

This was a tall order in the 1930s and early 1940s, when cancer therapeutics consisted only of surgical resection and very primitive forms of radiation therapy. Applicable only to neoplasia that was localized, these options were useless against malignancies in the blood, like acute lymphoblastic leukemia (ALL), but by January 1948 there was at least one glimmer of hope. At that time, one patient with ALL, 2-year-old Robert Sandler, was too ill to join his twin brother Elliott for snow play outside their home in the Dorchester section of Boston. Diagnosed back in August, Robert had suffered multiple episodes of fever, anemia, and thrombocytopenia. His illness had enlarged his spleen dramatically and caused pathologic bone fractures with excruciating bone pain, and for a while he couldn’t walk because of pressure on his lower spinal cord. All of this was the result of uncontrolled mitosis and cell division of lymphoblasts, immature lymphocytes. By December, these out-of-control cells had elevated the boy’s white blood cell count to a peak of 70,000/mcL, more than six times the high end of the normal range (4,500-11,000/mcL). This had happened despite treatment with an experimental drug, developed at Boston Children’s Hospital by Dr. Farber and his team, working on the assumption that inhibition of folate metabolism should slow the growth of tumor cells. On Dec. 28, however, Dr. Farber had switched the child to a new drug with a chemical structure just slightly different from the other agent’s.

Merely another chemical modification in a series of attempts by the research team, the new drug, aminopterin, was not expected to do anything dramatic, but Dr. Farber and the team had come such a long way since the middle of 1947, when he’d actually done the opposite of what he was doing now. On the basis of British research from India showing folic acid deficiency as the basis of a common type of anemia in malnourished people, Dr. Farber had reasoned that children with leukemia, who also suffered from anemia, might also benefit from folic acid supplementation. Even without prior rodent testing, Dr. Farber had tried giving the nutrient to patients with ALL, a strategy made possible by the presence of a spectacular chemist working on folic acid synthesis at Farber’s own hospital to help combat folate deficiency. Born into a poor Brahmin family in India, the chemist, Dr. Yellapragada SubbaRow, had begun life with so much stacked against him as to appear even less likely during childhood than the young Dr. Farber to grow up to make major contributions to medicine. Going through childhood with death all around him, Dr. SubbaRow was motivated to study medicine, but getting into medical school had been an uphill fight, given his family’s economic difficulty. Knowing that he’d also face discrimination on account of his low status after receiving admission to a medical program, SubbaRow could have made things a bit easier for himself by living within the norms of the British Imperial system, but as a supporter of Mohandas Gandhi’s nationalist movement, he boycotted British goods. As a medical student, this meant doing things like wearing Indian-made surgical gloves, instead of the English products that were expected of the students. Such actions led Dr. SubbaRow to receive a kind of second-rate medical degree, rather than the prestigious MBBS.

The political situation also led Dr. SubbaRow to emigrate to the United States, where, ironically, his medical degree initially was taken less seriously than it had been taken in his British-occupied homeland. He thus worked in the capacity of a hospital night porter at Peter Bent Brigham Hospital (the future Brigham and Women’s Hospital), doing menial tasks like changing sheets to make ends meet. He studied, however, and made enough of an impression to gain admission to the same institution that also admitted Farber through the backdoor, Harvard Medical School. This launched him into a research career in which he not only would be instrumental in developing folate antagonists and other classes of drugs, but also would make him the codiscoverer of the role of creatine phosphate and ATP in cellular energy metabolism. Sadly, even after obtaining his top-notch American credentials and contributing through his research to what you might say is a good chunk of the biochemistry pathways that first year medical students memorize without ever learning who discovered them, Dr. SubbaRow still faced prejudice for the rest of his life, which turned out to last only until the age of 53. To add insult to injury, he is rarely remembered for his role.

Dr. Farber proceeded with the folic acid supplementation idea in patients with ALL, even though ALL caused a hypoproliferative anemia, whereas anemia from folate deficiency was megaloblastic, meaning that erythrocytes were produced but they were oversized and dysfunctional. Tragically, folic acid had accelerated the disease process in children with ALL, but the process of chemical experimentation aimed at synthesizing folate also produced some compounds that mimicked chemical precursors of folate in a way that made them antifolates, inhibitors of folate metabolism. If folic acid made lymphoblasts grow faster, Dr. Farber had reasoned that antifolates should inhibit their growth. He thus asked the chemistry lab to focus on folate inhibitors. Testing aminopterin, beginning with young Robert Sandler at the end of December, is what proved his hypothesis correct. By late January, aminopterin had brought the child’s WBC count down to the realm of 12,000, just slightly above normal, with symptoms and signs abating as well, and by February, the child could play with his twin brother. It was not a cure; malignant lymphoblasts still showed on microscopy of Robert’s blood. While he and some 15 other children whom Dr. Farber treated in this early trial would all succumb to ALL, they experienced remission lasting several months.

This was a big deal because the concept of chemotherapy was based only on serendipitous observations of WBC counts dropping in soldiers exposed to nitrogen mustard gas during World War I and during an incident in World War II, yet aminopterin had been designed from the ground up. Though difficult to synthesize in quantities, there was no reason for Dr. Farber’s team not to keep tweaking the drug, and so they did. Replacing one hydrogen atom with a methyl group, they turned it into methotrexate.

Proving easier to synthesize and less toxic, methotrexate would become a workhorse for chemotherapy over the next couple of decades, but the capability of both methotrexate and aminopterin to blunt the growth of white blood cells and other cells did not go unnoticed outside the realm of oncology. As early as the 1950s, dermatologists were using aminopterin to treat psoriasis. This led to the approval of methotrexate for psoriasis in 1972.

Meanwhile, like oncology, infectious diseases, aviation medicine, and so many other areas of practice, rheumatology had gotten a major boost from research stemming from World War II. During the war, Dr. Philip Hench of the Mayo Clinic developed cortisone, which pilots used to stay alert and energetic during trans-Atlantic flights. But it turned out that cortisone had a powerful immunosuppressive effect that dramatically improved rheumatoid arthritis, leading Dr. Hench to receive the Nobel Prize in Physiology or Medicine in 1950. By the end of the 1950s, however, the significant side effects of long-term corticosteroid therapy were very clear, so over the next few decades there was a major effort to develop different treatments for RA and other rheumatologic diseases.

Top on the list of such agents was methotrexate, developed for RA in part by Dr. Michael Weinblatt of Brigham and Women’s Hospital in Boston. In the 1980s, Dr. Weinblatt published the first clinical trial showing the benefits of methotrexate for RA patients. This has since developed into a standard treatment, noticeably different from the original malignancy application in that it is a low-dose regimen. Patients taking methotrexate for RA typically receive no more than 25 mg per week orally, and often much less. Rheumatology today includes expertise in keeping long-term methotrexate therapy safe by monitoring liver function and through other routine tests. The routine nature of the therapy has brought methotrexate to the point of beckoning in a realm that Dr. Farber might not have predicted in his wildest imagination: cardiology. This is on account of the growing appreciation of the inflammatory process in the pathophysiology of atherosclerotic heart disease.

Meanwhile, being an antimetabolite, harmful to rapidly dividing cells, the danger of methotrexate to the embryo and fetus was recognized early. This made methotrexate off-limits to pregnant women, yet it also has made the drug useful as an abortifacient. Though not as good for medication abortion in unwanted but thriving pregnancies, where mifepristone/misoprostol has become the regimen of choice, methotrexate has become a workhorse in other obstetrical settings, such as for ending ectopic pregnancy.

Looking at the present and into the future, the potential for this very old medication looks wide open, as if it could go in any direction, so let’s wind up the discussion with the thought that we may be in for some surprises. Rather than jumping deeply into any rheumatologic issue, we spent most of this article weaving through other medical issues, but does this not make today’s story fairly analogous to rheumatology itself?

Dr. Warmflash is a physician from Portland, Ore. He reported no conflicts of interest.

This story was updated 2/10/2023.

A version of this article first appeared on Medscape.com.

If you could go back in time 75 years and tell Dr. Sidney Farber, the developer of methotrexate for cancer therapy, that 21st-century medicine would utilize his specially designed drug more in rheumatology than oncology, he might be surprised. He might scratch his head even more, hearing of his drug sparking interest in still other medical fields, like cardiology.

But drug repurposing is not so uncommon. One classic example is aspirin. Once the most common pain medication and used also in rheumatology, aspirin now finds a range of applications, from colorectal cancer to the prevention of cardiovascular and cerebrovascular thrombosis. Minoxidil is another example, developed for hypertension but used today mostly to stop hair loss. Perhaps most ironic is thalidomide, utilized today for leprosy and multiple myeloma, yet actually contraindicated for its original application, nausea of pregnancy.

Courtesy NIH

Methotrexate, thus, has much in common with other medical treatments, and yet its origin story is as unique and as fascinating as the story of Dr. Farber himself. While this is a rheumatology article, it’s also a story about the origin of a particular rheumatologic treatment, and so the story of that origin will take us mostly through a discussion of hematologic malignancy and of the clinical researcher who dared search for a cure.

Born in 1903, in Buffalo, New York, third of fourteen children of Jewish immigrants from Poland, Dr. Farber grew up in a household that was crowded but academically rigorous. His father, Simon, routinely brought home textbooks, assigning each child a book to read and on which to write a report. His mother, Matilda, was as devoted as her husband to raising the children to succeed in their adopted new country. Upstairs, the children were permitted to speak Yiddish, but downstairs they were required to use only English and German.

As a teen, Dr. Farber lived through the 1918 influenza pandemic that killed at least 50 million people worldwide, including more than 2,000 Buffalonians. This probably helped motivate him to study medicine, but with antisemitism overt in the America of the early 1920s, securing admission to a U.S. medical school was close to impossible. So, in what now seems like the greatest of ironies, Dr. Farber began medical studies in Germany, then transferred for the second year to a U.S. program that seemed adequate – Harvard Medical School, from which he graduated in 1927. From there, he trained as a pathologist, focusing ultimately on pediatric pathology. But, frustrated by case after case of malignancy, whose young victims he’d often have to autopsy, Dr. Farber decided that he wanted to advance the pitiful state of cancer therapeutics, especially for hematologic malignancy.

This was a tall order in the 1930s and early 1940s, when cancer therapeutics consisted only of surgical resection and very primitive forms of radiation therapy. Applicable only to neoplasia that was localized, these options were useless against malignancies in the blood, like acute lymphoblastic leukemia (ALL), but by January 1948 there was at least one glimmer of hope. At that time, one patient with ALL, 2-year-old Robert Sandler, was too ill to join his twin brother Elliott for snow play outside their home in the Dorchester section of Boston. Diagnosed back in August, Robert had suffered multiple episodes of fever, anemia, and thrombocytopenia. His illness had enlarged his spleen dramatically and caused pathologic bone fractures with excruciating bone pain, and for a while he couldn’t walk because of pressure on his lower spinal cord. All of this was the result of uncontrolled mitosis and cell division of lymphoblasts, immature lymphocytes. By December, these out-of-control cells had elevated the boy’s white blood cell count to a peak of 70,000/mcL, more than six times the high end of the normal range (4,500-11,000/mcL). This had happened despite treatment with an experimental drug, developed at Boston Children’s Hospital by Dr. Farber and his team, working on the assumption that inhibition of folate metabolism should slow the growth of tumor cells. On Dec. 28, however, Dr. Farber had switched the child to a new drug with a chemical structure just slightly different from the other agent’s.

Merely another chemical modification in a series of attempts by the research team, the new drug, aminopterin, was not expected to do anything dramatic, but Dr. Farber and the team had come such a long way since the middle of 1947, when he’d actually done the opposite of what he was doing now. On the basis of British research from India showing folic acid deficiency as the basis of a common type of anemia in malnourished people, Dr. Farber had reasoned that children with leukemia, who also suffered from anemia, might also benefit from folic acid supplementation. Even without prior rodent testing, Dr. Farber had tried giving the nutrient to patients with ALL, a strategy made possible by the presence of a spectacular chemist working on folic acid synthesis at Farber’s own hospital to help combat folate deficiency. Born into a poor Brahmin family in India, the chemist, Dr. Yellapragada SubbaRow, had begun life with so much stacked against him as to appear even less likely during childhood than the young Dr. Farber to grow up to make major contributions to medicine. Going through childhood with death all around him, Dr. SubbaRow was motivated to study medicine, but getting into medical school had been an uphill fight, given his family’s economic difficulty. Knowing that he’d also face discrimination on account of his low status after receiving admission to a medical program, SubbaRow could have made things a bit easier for himself by living within the norms of the British Imperial system, but as a supporter of Mohandas Gandhi’s nationalist movement, he boycotted British goods. As a medical student, this meant doing things like wearing Indian-made surgical gloves, instead of the English products that were expected of the students. Such actions led Dr. SubbaRow to receive a kind of second-rate medical degree, rather than the prestigious MBBS.

The political situation also led Dr. SubbaRow to emigrate to the United States, where, ironically, his medical degree initially was taken less seriously than it had been taken in his British-occupied homeland. He thus worked in the capacity of a hospital night porter at Peter Bent Brigham Hospital (the future Brigham and Women’s Hospital), doing menial tasks like changing sheets to make ends meet. He studied, however, and made enough of an impression to gain admission to the same institution that also admitted Farber through the backdoor, Harvard Medical School. This launched him into a research career in which he not only would be instrumental in developing folate antagonists and other classes of drugs, but also would make him the codiscoverer of the role of creatine phosphate and ATP in cellular energy metabolism. Sadly, even after obtaining his top-notch American credentials and contributing through his research to what you might say is a good chunk of the biochemistry pathways that first year medical students memorize without ever learning who discovered them, Dr. SubbaRow still faced prejudice for the rest of his life, which turned out to last only until the age of 53. To add insult to injury, he is rarely remembered for his role.

Dr. Farber proceeded with the folic acid supplementation idea in patients with ALL, even though ALL caused a hypoproliferative anemia, whereas anemia from folate deficiency was megaloblastic, meaning that erythrocytes were produced but they were oversized and dysfunctional. Tragically, folic acid had accelerated the disease process in children with ALL, but the process of chemical experimentation aimed at synthesizing folate also produced some compounds that mimicked chemical precursors of folate in a way that made them antifolates, inhibitors of folate metabolism. If folic acid made lymphoblasts grow faster, Dr. Farber had reasoned that antifolates should inhibit their growth. He thus asked the chemistry lab to focus on folate inhibitors. Testing aminopterin, beginning with young Robert Sandler at the end of December, is what proved his hypothesis correct. By late January, aminopterin had brought the child’s WBC count down to the realm of 12,000, just slightly above normal, with symptoms and signs abating as well, and by February, the child could play with his twin brother. It was not a cure; malignant lymphoblasts still showed on microscopy of Robert’s blood. While he and some 15 other children whom Dr. Farber treated in this early trial would all succumb to ALL, they experienced remission lasting several months.

This was a big deal because the concept of chemotherapy was based only on serendipitous observations of WBC counts dropping in soldiers exposed to nitrogen mustard gas during World War I and during an incident in World War II, yet aminopterin had been designed from the ground up. Though difficult to synthesize in quantities, there was no reason for Dr. Farber’s team not to keep tweaking the drug, and so they did. Replacing one hydrogen atom with a methyl group, they turned it into methotrexate.

Proving easier to synthesize and less toxic, methotrexate would become a workhorse for chemotherapy over the next couple of decades, but the capability of both methotrexate and aminopterin to blunt the growth of white blood cells and other cells did not go unnoticed outside the realm of oncology. As early as the 1950s, dermatologists were using aminopterin to treat psoriasis. This led to the approval of methotrexate for psoriasis in 1972.

Meanwhile, like oncology, infectious diseases, aviation medicine, and so many other areas of practice, rheumatology had gotten a major boost from research stemming from World War II. During the war, Dr. Philip Hench of the Mayo Clinic developed cortisone, which pilots used to stay alert and energetic during trans-Atlantic flights. But it turned out that cortisone had a powerful immunosuppressive effect that dramatically improved rheumatoid arthritis, leading Dr. Hench to receive the Nobel Prize in Physiology or Medicine in 1950. By the end of the 1950s, however, the significant side effects of long-term corticosteroid therapy were very clear, so over the next few decades there was a major effort to develop different treatments for RA and other rheumatologic diseases.

Top on the list of such agents was methotrexate, developed for RA in part by Dr. Michael Weinblatt of Brigham and Women’s Hospital in Boston. In the 1980s, Dr. Weinblatt published the first clinical trial showing the benefits of methotrexate for RA patients. This has since developed into a standard treatment, noticeably different from the original malignancy application in that it is a low-dose regimen. Patients taking methotrexate for RA typically receive no more than 25 mg per week orally, and often much less. Rheumatology today includes expertise in keeping long-term methotrexate therapy safe by monitoring liver function and through other routine tests. The routine nature of the therapy has brought methotrexate to the point of beckoning in a realm that Dr. Farber might not have predicted in his wildest imagination: cardiology. This is on account of the growing appreciation of the inflammatory process in the pathophysiology of atherosclerotic heart disease.

Meanwhile, being an antimetabolite, harmful to rapidly dividing cells, the danger of methotrexate to the embryo and fetus was recognized early. This made methotrexate off-limits to pregnant women, yet it also has made the drug useful as an abortifacient. Though not as good for medication abortion in unwanted but thriving pregnancies, where mifepristone/misoprostol has become the regimen of choice, methotrexate has become a workhorse in other obstetrical settings, such as for ending ectopic pregnancy.

Looking at the present and into the future, the potential for this very old medication looks wide open, as if it could go in any direction, so let’s wind up the discussion with the thought that we may be in for some surprises. Rather than jumping deeply into any rheumatologic issue, we spent most of this article weaving through other medical issues, but does this not make today’s story fairly analogous to rheumatology itself?

Dr. Warmflash is a physician from Portland, Ore. He reported no conflicts of interest.

This story was updated 2/10/2023.

A version of this article first appeared on Medscape.com.