Neuromuscular Disorders

AUSTIN, TEX. – Real-world effectiveness of ataluren for the treatment of Duchenne muscular dystrophy (DMD) with nonsense mutation was similar to the benefit seen in the randomized controlled trial that led to its European approval, according to new data.

“Participants in the STRIDE Registry [real-world patients] showed a reduction in functional decline over 48 weeks, compared with patients receiving placebo” in the trial, reported Abdallah Delage of PTC Therapeutics in Zug, Switzerland, and his associates.

Duchenne muscular dystrophy affects an estimated 1 in 3,600-6,000 male births globally, about 10%-15% of whom have nonsense mutation DMD. This mutation causes a truncated, nonfunctional dystrophin protein due to a premature stop codon, the authors explained. Ataluren “promotes ribosomal read-through of the premature stop codon to produce a full-length dystrophin protein,” they explained.

Ataluren is currently approved for ambulatory patients age 2 and older with nonsense mutation DMD in the European Union and several other European countries. Israel, Korea, Chile, and Ukraine have approved it for patients aged 5 and older.

The Strategic Targeting of Registries and International Database of Excellence (STRIDE) Registry contains real-world data from patients using ataluren as part of an ongoing multicenter observational postapproval safety study. The investigators are tracking patients for at least 5 years after enrollment in 14 countries where ataluren is approved or commercially available through early-access programs. Patients take 40 mg/kg daily: 10 mg/kg in the morning, 10 mg/kg midday, and 20 mg/kg in the evening.

The researchers compared outcomes in 216 patients in the STRIDE Registry with participants in a randomized controlled phase 3 study of ataluren involving 228 boys, aged 7-16, who received ataluren (n = 114) or placebo (n = 114) for 48 weeks. Patients were an average 9 years old in STRIDE and in both arms of the randomized controlled trial.

The STRIDE Registry participants, comprising 184 ambulatory and 26 nonambulatory patients at enrollment, had at least 48 weeks between their first and last assessment. All of the patients in the phase 3 study and 88.6% of the STRIDE Registry patients were receiving corticosteroids along with ataluren. The researchers compared the 184 ambulatory STRIDE participants with the participants of the randomized controlled trial for one primary and four secondary endpoints from baseline to 48 weeks.

For the primary endpoint, 6-minute walk distance, average distance was 35 meters shorter than baseline in STRIDE Registry participants (n = 66), 42.2 meters shorter in the patients receiving ataluren in the phase 3 study (n = 109), and 57.6 meters shorter in RCT patients receiving placebo in the phase 3 trial (n = 109).

A secondary endpoint, the time it took patients to walk or run 10 meters, increased 1.6 seconds from baseline to 48 weeks in STRIDE Registry participants (n = 61), 2.3 seconds in participants receiving ataluren in the phase 3 trial (n = 109), and 3.5 seconds in study participants receiving placebo (n = 110).

Another secondary endpoint, the change in time it took for patients to stand from supine position from baseline to 48 weeks, was 2.9 additional seconds for STRIDE participants (n = 55), 3.8 additional seconds in study participants receiving ataluren (n = 101), and 3.9 additional seconds in study participants receiving placebo (n = 96).

Two final secondary endpoints were the changes in time to climb four stairs and to descend four stairs from baseline to 48 weeks. STRIDE participants (n = 47) climbed four stairs 1.2 seconds more slowly at 48 weeks, compared with 2.7 seconds more slowly in the participants who received ataluren in the phase 3 trial (n = 105) and 4.5 seconds more slowly in those who received placebo. Descending four stairs took 0.5 more seconds at 48 weeks in STRIDE participants (n = 40), 2.2 more seconds in participants who received ataluren in the phase 3 trial (n = 106), and 4.0 more seconds in those who received placebo (n = 100).

At least one adverse event occurred in 20.7% of registry participants; seven of these were considered treatment related. Treatment-related side effects included abdominal pain, vomiting, headache, stomach ache, diarrhea, and increased serum lipids.

The study and STRIDE Registry is funded by PTC Therapeutics with TREAT-NMD and the Cooperative International Neuromuscular Research Group. Mr. Delage and five other authors are employees of PTC Therapeutics, and six authors had received speaker or consultancy fees or served on the advisory board of a variety of companies.

SOURCE: Delage A et al. AANEM 2019, Abstract 115.
 

AUSTIN, TEX. – Real-world effectiveness of ataluren for the treatment of Duchenne muscular dystrophy (DMD) with nonsense mutation was similar to the benefit seen in the randomized controlled trial that led to its European approval, according to new data.

“Participants in the STRIDE Registry [real-world patients] showed a reduction in functional decline over 48 weeks, compared with patients receiving placebo” in the trial, reported Abdallah Delage of PTC Therapeutics in Zug, Switzerland, and his associates.

Duchenne muscular dystrophy affects an estimated 1 in 3,600-6,000 male births globally, about 10%-15% of whom have nonsense mutation DMD. This mutation causes a truncated, nonfunctional dystrophin protein due to a premature stop codon, the authors explained. Ataluren “promotes ribosomal read-through of the premature stop codon to produce a full-length dystrophin protein,” they explained.

Ataluren is currently approved for ambulatory patients age 2 and older with nonsense mutation DMD in the European Union and several other European countries. Israel, Korea, Chile, and Ukraine have approved it for patients aged 5 and older.

The Strategic Targeting of Registries and International Database of Excellence (STRIDE) Registry contains real-world data from patients using ataluren as part of an ongoing multicenter observational postapproval safety study. The investigators are tracking patients for at least 5 years after enrollment in 14 countries where ataluren is approved or commercially available through early-access programs. Patients take 40 mg/kg daily: 10 mg/kg in the morning, 10 mg/kg midday, and 20 mg/kg in the evening.

The researchers compared outcomes in 216 patients in the STRIDE Registry with participants in a randomized controlled phase 3 study of ataluren involving 228 boys, aged 7-16, who received ataluren (n = 114) or placebo (n = 114) for 48 weeks. Patients were an average 9 years old in STRIDE and in both arms of the randomized controlled trial.

The STRIDE Registry participants, comprising 184 ambulatory and 26 nonambulatory patients at enrollment, had at least 48 weeks between their first and last assessment. All of the patients in the phase 3 study and 88.6% of the STRIDE Registry patients were receiving corticosteroids along with ataluren. The researchers compared the 184 ambulatory STRIDE participants with the participants of the randomized controlled trial for one primary and four secondary endpoints from baseline to 48 weeks.

For the primary endpoint, 6-minute walk distance, average distance was 35 meters shorter than baseline in STRIDE Registry participants (n = 66), 42.2 meters shorter in the patients receiving ataluren in the phase 3 study (n = 109), and 57.6 meters shorter in RCT patients receiving placebo in the phase 3 trial (n = 109).

A secondary endpoint, the time it took patients to walk or run 10 meters, increased 1.6 seconds from baseline to 48 weeks in STRIDE Registry participants (n = 61), 2.3 seconds in participants receiving ataluren in the phase 3 trial (n = 109), and 3.5 seconds in study participants receiving placebo (n = 110).

Another secondary endpoint, the change in time it took for patients to stand from supine position from baseline to 48 weeks, was 2.9 additional seconds for STRIDE participants (n = 55), 3.8 additional seconds in study participants receiving ataluren (n = 101), and 3.9 additional seconds in study participants receiving placebo (n = 96).

Two final secondary endpoints were the changes in time to climb four stairs and to descend four stairs from baseline to 48 weeks. STRIDE participants (n = 47) climbed four stairs 1.2 seconds more slowly at 48 weeks, compared with 2.7 seconds more slowly in the participants who received ataluren in the phase 3 trial (n = 105) and 4.5 seconds more slowly in those who received placebo. Descending four stairs took 0.5 more seconds at 48 weeks in STRIDE participants (n = 40), 2.2 more seconds in participants who received ataluren in the phase 3 trial (n = 106), and 4.0 more seconds in those who received placebo (n = 100).

At least one adverse event occurred in 20.7% of registry participants; seven of these were considered treatment related. Treatment-related side effects included abdominal pain, vomiting, headache, stomach ache, diarrhea, and increased serum lipids.

The study and STRIDE Registry is funded by PTC Therapeutics with TREAT-NMD and the Cooperative International Neuromuscular Research Group. Mr. Delage and five other authors are employees of PTC Therapeutics, and six authors had received speaker or consultancy fees or served on the advisory board of a variety of companies.

SOURCE: Delage A et al. AANEM 2019, Abstract 115.
 

AUSTIN, TEX. – Real-world effectiveness of ataluren for the treatment of Duchenne muscular dystrophy (DMD) with nonsense mutation was similar to the benefit seen in the randomized controlled trial that led to its European approval, according to new data.

“Participants in the STRIDE Registry [real-world patients] showed a reduction in functional decline over 48 weeks, compared with patients receiving placebo” in the trial, reported Abdallah Delage of PTC Therapeutics in Zug, Switzerland, and his associates.

Duchenne muscular dystrophy affects an estimated 1 in 3,600-6,000 male births globally, about 10%-15% of whom have nonsense mutation DMD. This mutation causes a truncated, nonfunctional dystrophin protein due to a premature stop codon, the authors explained. Ataluren “promotes ribosomal read-through of the premature stop codon to produce a full-length dystrophin protein,” they explained.

Ataluren is currently approved for ambulatory patients age 2 and older with nonsense mutation DMD in the European Union and several other European countries. Israel, Korea, Chile, and Ukraine have approved it for patients aged 5 and older.

The Strategic Targeting of Registries and International Database of Excellence (STRIDE) Registry contains real-world data from patients using ataluren as part of an ongoing multicenter observational postapproval safety study. The investigators are tracking patients for at least 5 years after enrollment in 14 countries where ataluren is approved or commercially available through early-access programs. Patients take 40 mg/kg daily: 10 mg/kg in the morning, 10 mg/kg midday, and 20 mg/kg in the evening.

The researchers compared outcomes in 216 patients in the STRIDE Registry with participants in a randomized controlled phase 3 study of ataluren involving 228 boys, aged 7-16, who received ataluren (n = 114) or placebo (n = 114) for 48 weeks. Patients were an average 9 years old in STRIDE and in both arms of the randomized controlled trial.

The STRIDE Registry participants, comprising 184 ambulatory and 26 nonambulatory patients at enrollment, had at least 48 weeks between their first and last assessment. All of the patients in the phase 3 study and 88.6% of the STRIDE Registry patients were receiving corticosteroids along with ataluren. The researchers compared the 184 ambulatory STRIDE participants with the participants of the randomized controlled trial for one primary and four secondary endpoints from baseline to 48 weeks.

For the primary endpoint, 6-minute walk distance, average distance was 35 meters shorter than baseline in STRIDE Registry participants (n = 66), 42.2 meters shorter in the patients receiving ataluren in the phase 3 study (n = 109), and 57.6 meters shorter in RCT patients receiving placebo in the phase 3 trial (n = 109).

A secondary endpoint, the time it took patients to walk or run 10 meters, increased 1.6 seconds from baseline to 48 weeks in STRIDE Registry participants (n = 61), 2.3 seconds in participants receiving ataluren in the phase 3 trial (n = 109), and 3.5 seconds in study participants receiving placebo (n = 110).

Another secondary endpoint, the change in time it took for patients to stand from supine position from baseline to 48 weeks, was 2.9 additional seconds for STRIDE participants (n = 55), 3.8 additional seconds in study participants receiving ataluren (n = 101), and 3.9 additional seconds in study participants receiving placebo (n = 96).

Two final secondary endpoints were the changes in time to climb four stairs and to descend four stairs from baseline to 48 weeks. STRIDE participants (n = 47) climbed four stairs 1.2 seconds more slowly at 48 weeks, compared with 2.7 seconds more slowly in the participants who received ataluren in the phase 3 trial (n = 105) and 4.5 seconds more slowly in those who received placebo. Descending four stairs took 0.5 more seconds at 48 weeks in STRIDE participants (n = 40), 2.2 more seconds in participants who received ataluren in the phase 3 trial (n = 106), and 4.0 more seconds in those who received placebo (n = 100).

At least one adverse event occurred in 20.7% of registry participants; seven of these were considered treatment related. Treatment-related side effects included abdominal pain, vomiting, headache, stomach ache, diarrhea, and increased serum lipids.

The study and STRIDE Registry is funded by PTC Therapeutics with TREAT-NMD and the Cooperative International Neuromuscular Research Group. Mr. Delage and five other authors are employees of PTC Therapeutics, and six authors had received speaker or consultancy fees or served on the advisory board of a variety of companies.

SOURCE: Delage A et al. AANEM 2019, Abstract 115.
 

AUSTIN, TEX. – When testing for acetylcholine receptor (AChR) autoantibodies in patients with suspected myasthenia gravis, testing for binding antibodies and for modulating antibodies is more accurate than testing for either subtype alone, researchers reported at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine. Testing for both subtypes may be the most accurate approach, regardless of whether patients have coexisting neuromuscular disorders, the researchers said.

“The advent of improved methods of detecting AChR autoantibodies has greatly facilitated the diagnosis of myasthenia gravis,” said Pritikanta Paul, MBBS, a neuromuscular fellow at Mayo Clinic in Rochester, Minn., and his colleagues. AChR antibody assays frequently are part of evaluations for myasthenia gravis, but clinicians lack consensus as to which antibody subtypes – binding, blocking, or modulating – should be tested. Clinicians test for binding antibodies most commonly, while studies have found blocking antibodies to be “least useful as an initial diagnostic test,” Dr. Paul and his colleagues said.

To assess how combinatorial antibody testing and the presence of coexisting neuromuscular disorders affect testing’s sensitivity and specificity, the researchers reviewed clinical and electrophysiologic testing data from 360 patients with suspected myasthenia gravis who underwent serologic autoantibody testing between 2012 and 2015.

Titers of AChR binding antibodies greater than 0.02 nmol/L were considered positive, as were AChR modulating antibodies more than 20%. The researchers used a greater than 10% decrement of the compound muscle action potential to repetitive nerve stimulation at 2 Hz or positive response on single-fiber EMG as electrophysiologic confirmation of myasthenia gravis.

In all, 123 of the 360 patients had a final clinical and electrophysiologic diagnosis of myasthenia gravis, including 23 with ocular myasthenia gravis and 100 with generalized myasthenia gravis.

The sensitivity of testing for AChR binding autoantibodies was 92%, and the sensitivity of testing for modulating autoantibodies was 90%. In comparison, the sensitivity of testing for either antibody subtype or both was 94%.

Among 45 patients with myasthenia gravis and coexisting neuromuscular disorders, including peripheral neuropathy, mononeuropathies, radiculopathy, and motor neuron disease, the sensitivities of testing for binding antibodies, modulating antibodies, and either or both were 96%, 91%, and 96%, respectively.

Of the 237 patients who did not have myasthenia gravis, 89 had electrophysiologic confirmation of alternative diagnoses. Among these 89 patients, AChR autoantibody testing yielded 11 false positives. Three patients tested positive for both binding and modulating antibodies, six for binding antibodies only, and two for modulating antibodies only. Those with false-positive results had diagnoses that were “diverse and clinically distinguishable from myasthenia gravis,” including myalgia, neuropathy, blurred vision, epilepsy, encephalopathy, and hemifacial spasm, the researchers said.

The researchers had no relevant disclosures.

[email protected]

SOURCE: Paul P et al. AANEM 2019, Abstract 236.

AUSTIN, TEX. – When testing for acetylcholine receptor (AChR) autoantibodies in patients with suspected myasthenia gravis, testing for binding antibodies and for modulating antibodies is more accurate than testing for either subtype alone, researchers reported at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine. Testing for both subtypes may be the most accurate approach, regardless of whether patients have coexisting neuromuscular disorders, the researchers said.

“The advent of improved methods of detecting AChR autoantibodies has greatly facilitated the diagnosis of myasthenia gravis,” said Pritikanta Paul, MBBS, a neuromuscular fellow at Mayo Clinic in Rochester, Minn., and his colleagues. AChR antibody assays frequently are part of evaluations for myasthenia gravis, but clinicians lack consensus as to which antibody subtypes – binding, blocking, or modulating – should be tested. Clinicians test for binding antibodies most commonly, while studies have found blocking antibodies to be “least useful as an initial diagnostic test,” Dr. Paul and his colleagues said.

To assess how combinatorial antibody testing and the presence of coexisting neuromuscular disorders affect testing’s sensitivity and specificity, the researchers reviewed clinical and electrophysiologic testing data from 360 patients with suspected myasthenia gravis who underwent serologic autoantibody testing between 2012 and 2015.

Titers of AChR binding antibodies greater than 0.02 nmol/L were considered positive, as were AChR modulating antibodies more than 20%. The researchers used a greater than 10% decrement of the compound muscle action potential to repetitive nerve stimulation at 2 Hz or positive response on single-fiber EMG as electrophysiologic confirmation of myasthenia gravis.

In all, 123 of the 360 patients had a final clinical and electrophysiologic diagnosis of myasthenia gravis, including 23 with ocular myasthenia gravis and 100 with generalized myasthenia gravis.

The sensitivity of testing for AChR binding autoantibodies was 92%, and the sensitivity of testing for modulating autoantibodies was 90%. In comparison, the sensitivity of testing for either antibody subtype or both was 94%.

Among 45 patients with myasthenia gravis and coexisting neuromuscular disorders, including peripheral neuropathy, mononeuropathies, radiculopathy, and motor neuron disease, the sensitivities of testing for binding antibodies, modulating antibodies, and either or both were 96%, 91%, and 96%, respectively.

Of the 237 patients who did not have myasthenia gravis, 89 had electrophysiologic confirmation of alternative diagnoses. Among these 89 patients, AChR autoantibody testing yielded 11 false positives. Three patients tested positive for both binding and modulating antibodies, six for binding antibodies only, and two for modulating antibodies only. Those with false-positive results had diagnoses that were “diverse and clinically distinguishable from myasthenia gravis,” including myalgia, neuropathy, blurred vision, epilepsy, encephalopathy, and hemifacial spasm, the researchers said.

The researchers had no relevant disclosures.

[email protected]

SOURCE: Paul P et al. AANEM 2019, Abstract 236.

AUSTIN, TEX. – When testing for acetylcholine receptor (AChR) autoantibodies in patients with suspected myasthenia gravis, testing for binding antibodies and for modulating antibodies is more accurate than testing for either subtype alone, researchers reported at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine. Testing for both subtypes may be the most accurate approach, regardless of whether patients have coexisting neuromuscular disorders, the researchers said.

“The advent of improved methods of detecting AChR autoantibodies has greatly facilitated the diagnosis of myasthenia gravis,” said Pritikanta Paul, MBBS, a neuromuscular fellow at Mayo Clinic in Rochester, Minn., and his colleagues. AChR antibody assays frequently are part of evaluations for myasthenia gravis, but clinicians lack consensus as to which antibody subtypes – binding, blocking, or modulating – should be tested. Clinicians test for binding antibodies most commonly, while studies have found blocking antibodies to be “least useful as an initial diagnostic test,” Dr. Paul and his colleagues said.

To assess how combinatorial antibody testing and the presence of coexisting neuromuscular disorders affect testing’s sensitivity and specificity, the researchers reviewed clinical and electrophysiologic testing data from 360 patients with suspected myasthenia gravis who underwent serologic autoantibody testing between 2012 and 2015.

Titers of AChR binding antibodies greater than 0.02 nmol/L were considered positive, as were AChR modulating antibodies more than 20%. The researchers used a greater than 10% decrement of the compound muscle action potential to repetitive nerve stimulation at 2 Hz or positive response on single-fiber EMG as electrophysiologic confirmation of myasthenia gravis.

In all, 123 of the 360 patients had a final clinical and electrophysiologic diagnosis of myasthenia gravis, including 23 with ocular myasthenia gravis and 100 with generalized myasthenia gravis.

The sensitivity of testing for AChR binding autoantibodies was 92%, and the sensitivity of testing for modulating autoantibodies was 90%. In comparison, the sensitivity of testing for either antibody subtype or both was 94%.

Among 45 patients with myasthenia gravis and coexisting neuromuscular disorders, including peripheral neuropathy, mononeuropathies, radiculopathy, and motor neuron disease, the sensitivities of testing for binding antibodies, modulating antibodies, and either or both were 96%, 91%, and 96%, respectively.

Of the 237 patients who did not have myasthenia gravis, 89 had electrophysiologic confirmation of alternative diagnoses. Among these 89 patients, AChR autoantibody testing yielded 11 false positives. Three patients tested positive for both binding and modulating antibodies, six for binding antibodies only, and two for modulating antibodies only. Those with false-positive results had diagnoses that were “diverse and clinically distinguishable from myasthenia gravis,” including myalgia, neuropathy, blurred vision, epilepsy, encephalopathy, and hemifacial spasm, the researchers said.

The researchers had no relevant disclosures.

[email protected]

SOURCE: Paul P et al. AANEM 2019, Abstract 236.

AUSTIN, TEX. – Patients with chronic inflammatory demyelinating polyneuropathy (CIDP) who receive intravenous immunoglobulin (IVIg) appear to have an increased risk of thromboembolic events if it is administered with a central venous access device (CVAD) when compared against those without a CVAD, according to a recent study.

Although CVADs can reliably deliver IVIg, they also represent an established risk factor for thromboembolic events, Ami Patel, PhD, a senior epidemiologist at CSL Behring, and colleagues noted on their poster at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

The results suggest a need for physicians to be vigilant about patients’ potential risk factors for thromboembolic events, Dr. Patel said in an interview. Further research is planned, however, because the current study did not control for other risk factors or explore other possible confounding, she said.

Dr. Patel and her associates analyzed U.S. claims data (IBM/Truven MarketScan) from 2006 to 2018 and included all patients with a CIDP diagnosis claim and a postdiagnosis code for IVIg. A code for CVAD up to 2 months before CIDP diagnosis without removal before IVIg treatment ended determined those with CVAD exposure, and thromboembolic events included any codes related to arterial, venous, or vascular prostheses.

The researchers then compared patients in a case-control fashion, matching each one with a CVAD to five patients of similar demographics without a CVAD. Characteristics used for matching included medical insurance type, prescription data availability, sex, age, geographic region, and years enrolled in the database.

Among 7,447 patients with at least one IVIg claim, 11.8% (n = 882) had CVAD exposure and 88.2% (n = 6,565) did not. Of those without a CVAD, 3,642 patients were matched to patients with CVAD. A quarter (25.4%) of patients with a CVAD had a thromboembolic event, compared with 11.2% of matched patients without CVADs (P less than .0001).

In the year leading up to IVIg therapy, 16.9% of those with a CVAD and 10.9% of matched patients without one had a previous thromboembolic event (P less than .0001). Patients with a CVAD also had significantly higher rates of hypertension (51.9% vs. 45.0% with placebo; P less than .001) and anticoagulation therapy (7.0% vs. 5.2% with placebo; P less than .05). Differences between the groups were not significant for diabetes (26.9% vs. 24.2%) and hyperlipidemia (19.1% vs. 17.8%).

Occlusion and stenosis of the carotid artery was the most common arterial thromboembolic outcome, occurring in 5.3% of those with a CVAD and in 2.8% of those without a CVAD. The most common venous thromboembolic event was acute venous embolism and thrombosis of lower-extremity deep vessels, which occurred in 7% of those with a CVAD and in 1.8% of those without.

The researchers also compared inpatient admissions and emergency department visits among those with and without a CVAD; both rates were higher in patients with a CVAD. Visits to the emergency department occurred at a rate of 0.14 events per month for those with a CVAD (2.01 distinct months with a claim) and 0.09 events per month for those without a CVAD (0.65 distinct months with a claim). Patients with a CVAD had 1.44 months with an inpatient admissions claim, in comparison with 0.41 months among matched patients without a CVAD. Inpatient admission frequency per month was 0.14 for those with a CVAD and 0.08 for those without.

The research was funded by CSL Behring. Dr. Patel and two of the other five authors are employees of CSL Behring.

SOURCE: Patel A et al. AANEM 2019, Abstract 94.

AUSTIN, TEX. – Patients with chronic inflammatory demyelinating polyneuropathy (CIDP) who receive intravenous immunoglobulin (IVIg) appear to have an increased risk of thromboembolic events if it is administered with a central venous access device (CVAD) when compared against those without a CVAD, according to a recent study.

Although CVADs can reliably deliver IVIg, they also represent an established risk factor for thromboembolic events, Ami Patel, PhD, a senior epidemiologist at CSL Behring, and colleagues noted on their poster at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

The results suggest a need for physicians to be vigilant about patients’ potential risk factors for thromboembolic events, Dr. Patel said in an interview. Further research is planned, however, because the current study did not control for other risk factors or explore other possible confounding, she said.

Dr. Patel and her associates analyzed U.S. claims data (IBM/Truven MarketScan) from 2006 to 2018 and included all patients with a CIDP diagnosis claim and a postdiagnosis code for IVIg. A code for CVAD up to 2 months before CIDP diagnosis without removal before IVIg treatment ended determined those with CVAD exposure, and thromboembolic events included any codes related to arterial, venous, or vascular prostheses.

The researchers then compared patients in a case-control fashion, matching each one with a CVAD to five patients of similar demographics without a CVAD. Characteristics used for matching included medical insurance type, prescription data availability, sex, age, geographic region, and years enrolled in the database.

Among 7,447 patients with at least one IVIg claim, 11.8% (n = 882) had CVAD exposure and 88.2% (n = 6,565) did not. Of those without a CVAD, 3,642 patients were matched to patients with CVAD. A quarter (25.4%) of patients with a CVAD had a thromboembolic event, compared with 11.2% of matched patients without CVADs (P less than .0001).

In the year leading up to IVIg therapy, 16.9% of those with a CVAD and 10.9% of matched patients without one had a previous thromboembolic event (P less than .0001). Patients with a CVAD also had significantly higher rates of hypertension (51.9% vs. 45.0% with placebo; P less than .001) and anticoagulation therapy (7.0% vs. 5.2% with placebo; P less than .05). Differences between the groups were not significant for diabetes (26.9% vs. 24.2%) and hyperlipidemia (19.1% vs. 17.8%).

Occlusion and stenosis of the carotid artery was the most common arterial thromboembolic outcome, occurring in 5.3% of those with a CVAD and in 2.8% of those without a CVAD. The most common venous thromboembolic event was acute venous embolism and thrombosis of lower-extremity deep vessels, which occurred in 7% of those with a CVAD and in 1.8% of those without.

The researchers also compared inpatient admissions and emergency department visits among those with and without a CVAD; both rates were higher in patients with a CVAD. Visits to the emergency department occurred at a rate of 0.14 events per month for those with a CVAD (2.01 distinct months with a claim) and 0.09 events per month for those without a CVAD (0.65 distinct months with a claim). Patients with a CVAD had 1.44 months with an inpatient admissions claim, in comparison with 0.41 months among matched patients without a CVAD. Inpatient admission frequency per month was 0.14 for those with a CVAD and 0.08 for those without.

The research was funded by CSL Behring. Dr. Patel and two of the other five authors are employees of CSL Behring.

SOURCE: Patel A et al. AANEM 2019, Abstract 94.

AUSTIN, TEX. – Patients with chronic inflammatory demyelinating polyneuropathy (CIDP) who receive intravenous immunoglobulin (IVIg) appear to have an increased risk of thromboembolic events if it is administered with a central venous access device (CVAD) when compared against those without a CVAD, according to a recent study.

Although CVADs can reliably deliver IVIg, they also represent an established risk factor for thromboembolic events, Ami Patel, PhD, a senior epidemiologist at CSL Behring, and colleagues noted on their poster at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

The results suggest a need for physicians to be vigilant about patients’ potential risk factors for thromboembolic events, Dr. Patel said in an interview. Further research is planned, however, because the current study did not control for other risk factors or explore other possible confounding, she said.

Dr. Patel and her associates analyzed U.S. claims data (IBM/Truven MarketScan) from 2006 to 2018 and included all patients with a CIDP diagnosis claim and a postdiagnosis code for IVIg. A code for CVAD up to 2 months before CIDP diagnosis without removal before IVIg treatment ended determined those with CVAD exposure, and thromboembolic events included any codes related to arterial, venous, or vascular prostheses.

The researchers then compared patients in a case-control fashion, matching each one with a CVAD to five patients of similar demographics without a CVAD. Characteristics used for matching included medical insurance type, prescription data availability, sex, age, geographic region, and years enrolled in the database.

Among 7,447 patients with at least one IVIg claim, 11.8% (n = 882) had CVAD exposure and 88.2% (n = 6,565) did not. Of those without a CVAD, 3,642 patients were matched to patients with CVAD. A quarter (25.4%) of patients with a CVAD had a thromboembolic event, compared with 11.2% of matched patients without CVADs (P less than .0001).

In the year leading up to IVIg therapy, 16.9% of those with a CVAD and 10.9% of matched patients without one had a previous thromboembolic event (P less than .0001). Patients with a CVAD also had significantly higher rates of hypertension (51.9% vs. 45.0% with placebo; P less than .001) and anticoagulation therapy (7.0% vs. 5.2% with placebo; P less than .05). Differences between the groups were not significant for diabetes (26.9% vs. 24.2%) and hyperlipidemia (19.1% vs. 17.8%).

Occlusion and stenosis of the carotid artery was the most common arterial thromboembolic outcome, occurring in 5.3% of those with a CVAD and in 2.8% of those without a CVAD. The most common venous thromboembolic event was acute venous embolism and thrombosis of lower-extremity deep vessels, which occurred in 7% of those with a CVAD and in 1.8% of those without.

The researchers also compared inpatient admissions and emergency department visits among those with and without a CVAD; both rates were higher in patients with a CVAD. Visits to the emergency department occurred at a rate of 0.14 events per month for those with a CVAD (2.01 distinct months with a claim) and 0.09 events per month for those without a CVAD (0.65 distinct months with a claim). Patients with a CVAD had 1.44 months with an inpatient admissions claim, in comparison with 0.41 months among matched patients without a CVAD. Inpatient admission frequency per month was 0.14 for those with a CVAD and 0.08 for those without.

The research was funded by CSL Behring. Dr. Patel and two of the other five authors are employees of CSL Behring.

SOURCE: Patel A et al. AANEM 2019, Abstract 94.

AUSTIN, TEX. – A three-drug combination agent called PXT3003 led to an improvement in symptoms for patients with Charcot-Marie-Tooth (CMT) disease type 1A, according to new research.

“The study has established for the first time that patients after up to 15 months of treatment had a statistically significant and clinically relevant disability improvement as illustrated by the change from baseline of their ONLS [Overall Neurology Limitations Scale] scale,” concluded Florian Thomas, MD, PhD, of Hackensack (N.J.) University Medical Center, and his associates at Pharnext. “PXT3003 with dose 4 has at least stabilized, even improved, the disease.”

The researchers presented their findings in a poster at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

The PLEO-CMT study was an international, multicenter, randomized, double-blind, placebo-controlled, phase 3 trial that evaluated the efficacy and safety of PXT3003, an oral 3-drug combination, for CMT1A. CMT1A neuropathy, occurring in an estimated 1 in 5,000 people, is characterized by distal muscle atrophy that affects walking and causes stocking-glove sensory loss and lower quality of life.

The trial enrolled 323 patients, aged 16-65, who had mild to moderate CMT1A that had been genetically confirmed. The modified full set analysis (n = 235), which represented the main study analysis for the primary endpoint, included a placebo group of 87 participants while two other groups received one of two doses of the fixed-dose drug combination twice daily: Ninety-three participants received 3 mg baclofen, 0.35 mg naltrexone, and 105 mg sorbitol (dose 1), and 55 participants received twice that dose (dose 2).

The primary endpoint was mean change from baseline to 12 and 15 months on the ONLS. At baseline, 90% of patients had an ONLS score of 2-4, and the researchers determined an average 0.3 points reduction to be a clinically meaningful effect.

Secondary endpoints included the 10-meter walk test, the 9-hole peg test, and a subscore of Charcot-Marie-Tooth neuropathy score version 2 (CMTNSv2).

Only those taking the higher dose (dose 2) showed a clinically significant drop in ONLS, –0.37 points, compared with those taking placebo (P = .0008). The in-group change from baseline to 15 months in ONLS score for patients taking dose 2 showed a trend of improvement that did not reach significance (–0.20; P = .098).

Participants receiving dose 2 of PXT3003 also walked 0.47 seconds faster on the 10-meter walk test, compared with those receiving placebo (P = .016). No significant differences occurred in the other secondary endpoints, although nonsignificant trends of improvement occurred.

Treatment-emergent adverse events were similar across all three groups and led to trial withdrawal at similar rates for dose 1 (5.5%), dose 2 (5.3%), and placebo (5.9%). One serious adverse event, benign thyroid adenoma, led to trial withdrawal, but no serious adverse events occurred related to the treatment.

Pharnext funded the research. Dr. Thomas is a researcher with Pharnext and Acceleron and has received speaking or advisory board fees from Novartis, Acceleron, Sanofi, and Genentech. The other seven authors are employees of Pharnext.

SOURCE: Thomas F et al. AANEM 2019, Abstract 92.

AUSTIN, TEX. – A three-drug combination agent called PXT3003 led to an improvement in symptoms for patients with Charcot-Marie-Tooth (CMT) disease type 1A, according to new research.

“The study has established for the first time that patients after up to 15 months of treatment had a statistically significant and clinically relevant disability improvement as illustrated by the change from baseline of their ONLS [Overall Neurology Limitations Scale] scale,” concluded Florian Thomas, MD, PhD, of Hackensack (N.J.) University Medical Center, and his associates at Pharnext. “PXT3003 with dose 4 has at least stabilized, even improved, the disease.”

The researchers presented their findings in a poster at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

The PLEO-CMT study was an international, multicenter, randomized, double-blind, placebo-controlled, phase 3 trial that evaluated the efficacy and safety of PXT3003, an oral 3-drug combination, for CMT1A. CMT1A neuropathy, occurring in an estimated 1 in 5,000 people, is characterized by distal muscle atrophy that affects walking and causes stocking-glove sensory loss and lower quality of life.

The trial enrolled 323 patients, aged 16-65, who had mild to moderate CMT1A that had been genetically confirmed. The modified full set analysis (n = 235), which represented the main study analysis for the primary endpoint, included a placebo group of 87 participants while two other groups received one of two doses of the fixed-dose drug combination twice daily: Ninety-three participants received 3 mg baclofen, 0.35 mg naltrexone, and 105 mg sorbitol (dose 1), and 55 participants received twice that dose (dose 2).

The primary endpoint was mean change from baseline to 12 and 15 months on the ONLS. At baseline, 90% of patients had an ONLS score of 2-4, and the researchers determined an average 0.3 points reduction to be a clinically meaningful effect.

Secondary endpoints included the 10-meter walk test, the 9-hole peg test, and a subscore of Charcot-Marie-Tooth neuropathy score version 2 (CMTNSv2).

Only those taking the higher dose (dose 2) showed a clinically significant drop in ONLS, –0.37 points, compared with those taking placebo (P = .0008). The in-group change from baseline to 15 months in ONLS score for patients taking dose 2 showed a trend of improvement that did not reach significance (–0.20; P = .098).

Participants receiving dose 2 of PXT3003 also walked 0.47 seconds faster on the 10-meter walk test, compared with those receiving placebo (P = .016). No significant differences occurred in the other secondary endpoints, although nonsignificant trends of improvement occurred.

Treatment-emergent adverse events were similar across all three groups and led to trial withdrawal at similar rates for dose 1 (5.5%), dose 2 (5.3%), and placebo (5.9%). One serious adverse event, benign thyroid adenoma, led to trial withdrawal, but no serious adverse events occurred related to the treatment.

Pharnext funded the research. Dr. Thomas is a researcher with Pharnext and Acceleron and has received speaking or advisory board fees from Novartis, Acceleron, Sanofi, and Genentech. The other seven authors are employees of Pharnext.

SOURCE: Thomas F et al. AANEM 2019, Abstract 92.

AUSTIN, TEX. – A three-drug combination agent called PXT3003 led to an improvement in symptoms for patients with Charcot-Marie-Tooth (CMT) disease type 1A, according to new research.

“The study has established for the first time that patients after up to 15 months of treatment had a statistically significant and clinically relevant disability improvement as illustrated by the change from baseline of their ONLS [Overall Neurology Limitations Scale] scale,” concluded Florian Thomas, MD, PhD, of Hackensack (N.J.) University Medical Center, and his associates at Pharnext. “PXT3003 with dose 4 has at least stabilized, even improved, the disease.”

The researchers presented their findings in a poster at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

The PLEO-CMT study was an international, multicenter, randomized, double-blind, placebo-controlled, phase 3 trial that evaluated the efficacy and safety of PXT3003, an oral 3-drug combination, for CMT1A. CMT1A neuropathy, occurring in an estimated 1 in 5,000 people, is characterized by distal muscle atrophy that affects walking and causes stocking-glove sensory loss and lower quality of life.

The trial enrolled 323 patients, aged 16-65, who had mild to moderate CMT1A that had been genetically confirmed. The modified full set analysis (n = 235), which represented the main study analysis for the primary endpoint, included a placebo group of 87 participants while two other groups received one of two doses of the fixed-dose drug combination twice daily: Ninety-three participants received 3 mg baclofen, 0.35 mg naltrexone, and 105 mg sorbitol (dose 1), and 55 participants received twice that dose (dose 2).

The primary endpoint was mean change from baseline to 12 and 15 months on the ONLS. At baseline, 90% of patients had an ONLS score of 2-4, and the researchers determined an average 0.3 points reduction to be a clinically meaningful effect.

Secondary endpoints included the 10-meter walk test, the 9-hole peg test, and a subscore of Charcot-Marie-Tooth neuropathy score version 2 (CMTNSv2).

Only those taking the higher dose (dose 2) showed a clinically significant drop in ONLS, –0.37 points, compared with those taking placebo (P = .0008). The in-group change from baseline to 15 months in ONLS score for patients taking dose 2 showed a trend of improvement that did not reach significance (–0.20; P = .098).

Participants receiving dose 2 of PXT3003 also walked 0.47 seconds faster on the 10-meter walk test, compared with those receiving placebo (P = .016). No significant differences occurred in the other secondary endpoints, although nonsignificant trends of improvement occurred.

Treatment-emergent adverse events were similar across all three groups and led to trial withdrawal at similar rates for dose 1 (5.5%), dose 2 (5.3%), and placebo (5.9%). One serious adverse event, benign thyroid adenoma, led to trial withdrawal, but no serious adverse events occurred related to the treatment.

Pharnext funded the research. Dr. Thomas is a researcher with Pharnext and Acceleron and has received speaking or advisory board fees from Novartis, Acceleron, Sanofi, and Genentech. The other seven authors are employees of Pharnext.

SOURCE: Thomas F et al. AANEM 2019, Abstract 92.

CHARLOTTE, N.C. – Treatment of boys with Duchenne muscular dystrophy (DMD) with an investigational nuclear factor–kappa B (NF-kB) inhibitor may slow disease progression as assessed by MRI and functional measures, according to an analysis of phase 2 trial data presented at the annual meeting of the Child Neurology Society.

Jake Remaly/MDedge News

The NF-kB pathway is “fundamental to the pathogenesis and biology of DMD,” said Richard Finkel, MD, chief of neurology at Nemours Children’s Health System in Orlando and principal investigator for the phase 2 study, known as MoveDMD.

A lack of dystrophin, combined with the mechanical stress of muscle contraction, activates the NF-kB pathway and inhibits muscle regeneration. “It is known that there is inflammation and fibrosis and release of cytokines early in life” in patients with DMD, Dr. Finkel said.

Independent of mutation

Edasalonexent is an NF-kB inhibitor that is being developed by Catabasis as a therapy for patients with DMD regardless of the genetic mutation that is causing the disease. It may be used as monotherapy or with other dystrophin-targeted treatments, Dr. Finkel said.

In a mouse model of DMD, an analog of the drug reduced muscle inflammation and increased the force of diaphragm muscle. To assess edasalonexent’s safety, pharmacokinetics, and effects on functional measures and MRI in patients with DMD, Dr. Finkel and colleagues conducted the MoveDMD trial. Investigators enrolled boys aged 4 years to younger than 8 years who were not receiving treatment with corticosteroids.

Researchers first examined drug safety and pharmacokinetics in 17 boys who received the treatment for 1 week. The investigators then followed 16 of these patients off treatment for as long as 6 months. This off-treatment period was followed by a phase 2, placebo-controlled period, during which the 16 patients and another 15 patients received edasalonexent 67 mg/kg/day, edasalonexent 100 mg/kg/day, or placebo for 12 weeks. Patients subsequently entered an open-label extension study.

Dr. Finkel presented a comparison of outcomes during the off-treatment period with outcomes during the open-label extension. “We used these boys as their own internal control, if you wish,” he said.

Creatine kinase levels decreased soon after treatment, as did other markers of muscle disease. The drug “seems to have an early and sustained biomarker response,” Dr. Finkel said.

Annualized rate of change on lower leg muscle MRI-T2 decreased. “There is a relative reduction and stabilization from week 12 all the way out through the open-label extension to 72 weeks,” he said. “It suggests that there is an early and sustained response in stabilization of the MRI as a biomarker.”

Timed function tests

A comparison of the annualized rates of change on timed function tests – including the 10-meter walk/run, time-to-stand, and four-stair-climb, and the North Star Ambulatory Assessment – during the off-treatment and on-treatment periods indicated slowing of disease progression with treatment. “Shortly after starting on drug ... there was a relative stabilization in each of these measures,” Dr. Finkel said.

In addition, the researchers observed an early signal of possible cardiac benefit. Mean heart rate at baseline was 99 bpm. On treatment, it decreased to 92 bpm. “Boys with DMD die typically of cardiomyopathy, so it is important to try to address the cardiac status,” he said.

The drug was safe and well tolerated. Most participants experienced mild gastrointestinal issues, which typically were transient. One serious adverse event during the trial occurred in a patient receiving placebo. Patients tended to have a stable body mass index during treatment, Dr. Finkel said.

During the open-label extension, patients had “clinically meaningful slowing of disease progression on edasalonexent,” relative to the off-treatment period, Dr. Finkel said. Investigators plan to further study edasalonexent for the treatment of DMD in a phase 3 trial. The phase 3 study, PolarisDMD, recently completed enrollment at 40 sites. Results could be available in about a year, Dr. Finkel said.

The study was sponsored by Catabasis. Dr. Finkel disclosed consulting work and grants or research support from Catabasis and other companies.

[email protected]

SOURCE: Finkel R et al. CNS 2019. Abstract PL1-3.

CHARLOTTE, N.C. – Treatment of boys with Duchenne muscular dystrophy (DMD) with an investigational nuclear factor–kappa B (NF-kB) inhibitor may slow disease progression as assessed by MRI and functional measures, according to an analysis of phase 2 trial data presented at the annual meeting of the Child Neurology Society.

Jake Remaly/MDedge News

The NF-kB pathway is “fundamental to the pathogenesis and biology of DMD,” said Richard Finkel, MD, chief of neurology at Nemours Children’s Health System in Orlando and principal investigator for the phase 2 study, known as MoveDMD.

A lack of dystrophin, combined with the mechanical stress of muscle contraction, activates the NF-kB pathway and inhibits muscle regeneration. “It is known that there is inflammation and fibrosis and release of cytokines early in life” in patients with DMD, Dr. Finkel said.

Independent of mutation

Edasalonexent is an NF-kB inhibitor that is being developed by Catabasis as a therapy for patients with DMD regardless of the genetic mutation that is causing the disease. It may be used as monotherapy or with other dystrophin-targeted treatments, Dr. Finkel said.

In a mouse model of DMD, an analog of the drug reduced muscle inflammation and increased the force of diaphragm muscle. To assess edasalonexent’s safety, pharmacokinetics, and effects on functional measures and MRI in patients with DMD, Dr. Finkel and colleagues conducted the MoveDMD trial. Investigators enrolled boys aged 4 years to younger than 8 years who were not receiving treatment with corticosteroids.

Researchers first examined drug safety and pharmacokinetics in 17 boys who received the treatment for 1 week. The investigators then followed 16 of these patients off treatment for as long as 6 months. This off-treatment period was followed by a phase 2, placebo-controlled period, during which the 16 patients and another 15 patients received edasalonexent 67 mg/kg/day, edasalonexent 100 mg/kg/day, or placebo for 12 weeks. Patients subsequently entered an open-label extension study.

Dr. Finkel presented a comparison of outcomes during the off-treatment period with outcomes during the open-label extension. “We used these boys as their own internal control, if you wish,” he said.

Creatine kinase levels decreased soon after treatment, as did other markers of muscle disease. The drug “seems to have an early and sustained biomarker response,” Dr. Finkel said.

Annualized rate of change on lower leg muscle MRI-T2 decreased. “There is a relative reduction and stabilization from week 12 all the way out through the open-label extension to 72 weeks,” he said. “It suggests that there is an early and sustained response in stabilization of the MRI as a biomarker.”

Timed function tests

A comparison of the annualized rates of change on timed function tests – including the 10-meter walk/run, time-to-stand, and four-stair-climb, and the North Star Ambulatory Assessment – during the off-treatment and on-treatment periods indicated slowing of disease progression with treatment. “Shortly after starting on drug ... there was a relative stabilization in each of these measures,” Dr. Finkel said.

In addition, the researchers observed an early signal of possible cardiac benefit. Mean heart rate at baseline was 99 bpm. On treatment, it decreased to 92 bpm. “Boys with DMD die typically of cardiomyopathy, so it is important to try to address the cardiac status,” he said.

The drug was safe and well tolerated. Most participants experienced mild gastrointestinal issues, which typically were transient. One serious adverse event during the trial occurred in a patient receiving placebo. Patients tended to have a stable body mass index during treatment, Dr. Finkel said.

During the open-label extension, patients had “clinically meaningful slowing of disease progression on edasalonexent,” relative to the off-treatment period, Dr. Finkel said. Investigators plan to further study edasalonexent for the treatment of DMD in a phase 3 trial. The phase 3 study, PolarisDMD, recently completed enrollment at 40 sites. Results could be available in about a year, Dr. Finkel said.

The study was sponsored by Catabasis. Dr. Finkel disclosed consulting work and grants or research support from Catabasis and other companies.

[email protected]

SOURCE: Finkel R et al. CNS 2019. Abstract PL1-3.

CHARLOTTE, N.C. – Treatment of boys with Duchenne muscular dystrophy (DMD) with an investigational nuclear factor–kappa B (NF-kB) inhibitor may slow disease progression as assessed by MRI and functional measures, according to an analysis of phase 2 trial data presented at the annual meeting of the Child Neurology Society.

Jake Remaly/MDedge News

The NF-kB pathway is “fundamental to the pathogenesis and biology of DMD,” said Richard Finkel, MD, chief of neurology at Nemours Children’s Health System in Orlando and principal investigator for the phase 2 study, known as MoveDMD.

A lack of dystrophin, combined with the mechanical stress of muscle contraction, activates the NF-kB pathway and inhibits muscle regeneration. “It is known that there is inflammation and fibrosis and release of cytokines early in life” in patients with DMD, Dr. Finkel said.

Independent of mutation

Edasalonexent is an NF-kB inhibitor that is being developed by Catabasis as a therapy for patients with DMD regardless of the genetic mutation that is causing the disease. It may be used as monotherapy or with other dystrophin-targeted treatments, Dr. Finkel said.

In a mouse model of DMD, an analog of the drug reduced muscle inflammation and increased the force of diaphragm muscle. To assess edasalonexent’s safety, pharmacokinetics, and effects on functional measures and MRI in patients with DMD, Dr. Finkel and colleagues conducted the MoveDMD trial. Investigators enrolled boys aged 4 years to younger than 8 years who were not receiving treatment with corticosteroids.

Researchers first examined drug safety and pharmacokinetics in 17 boys who received the treatment for 1 week. The investigators then followed 16 of these patients off treatment for as long as 6 months. This off-treatment period was followed by a phase 2, placebo-controlled period, during which the 16 patients and another 15 patients received edasalonexent 67 mg/kg/day, edasalonexent 100 mg/kg/day, or placebo for 12 weeks. Patients subsequently entered an open-label extension study.

Dr. Finkel presented a comparison of outcomes during the off-treatment period with outcomes during the open-label extension. “We used these boys as their own internal control, if you wish,” he said.

Creatine kinase levels decreased soon after treatment, as did other markers of muscle disease. The drug “seems to have an early and sustained biomarker response,” Dr. Finkel said.

Annualized rate of change on lower leg muscle MRI-T2 decreased. “There is a relative reduction and stabilization from week 12 all the way out through the open-label extension to 72 weeks,” he said. “It suggests that there is an early and sustained response in stabilization of the MRI as a biomarker.”

Timed function tests

A comparison of the annualized rates of change on timed function tests – including the 10-meter walk/run, time-to-stand, and four-stair-climb, and the North Star Ambulatory Assessment – during the off-treatment and on-treatment periods indicated slowing of disease progression with treatment. “Shortly after starting on drug ... there was a relative stabilization in each of these measures,” Dr. Finkel said.

In addition, the researchers observed an early signal of possible cardiac benefit. Mean heart rate at baseline was 99 bpm. On treatment, it decreased to 92 bpm. “Boys with DMD die typically of cardiomyopathy, so it is important to try to address the cardiac status,” he said.

The drug was safe and well tolerated. Most participants experienced mild gastrointestinal issues, which typically were transient. One serious adverse event during the trial occurred in a patient receiving placebo. Patients tended to have a stable body mass index during treatment, Dr. Finkel said.

During the open-label extension, patients had “clinically meaningful slowing of disease progression on edasalonexent,” relative to the off-treatment period, Dr. Finkel said. Investigators plan to further study edasalonexent for the treatment of DMD in a phase 3 trial. The phase 3 study, PolarisDMD, recently completed enrollment at 40 sites. Results could be available in about a year, Dr. Finkel said.

The study was sponsored by Catabasis. Dr. Finkel disclosed consulting work and grants or research support from Catabasis and other companies.

[email protected]

SOURCE: Finkel R et al. CNS 2019. Abstract PL1-3.

AUSTIN, TEX. – Patients with peripheral neuropathy may benefit from genetic testing to determine of the cause of their neuropathy even if they do not have a family history of the condition, according to new research.

The same research identified more than 80 genetic variants in patients with neuropathy who lacked any other known genetic mutations, potentially representing not-yet-identified pathogenic mutations.

Sasa Zivkovic, MD, PhD, of the University of Pittsburgh Medical Center (UPMC), and associates shared a poster of their findings at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

The researchers conducted next-generation sequencing (NGS) on 85 adult patients with peripheral neuropathy at the UPMC Neuromuscular Clinic during May 2017–Feb. 2019. The targeted NGS panel included 70 genes. The patients, aged 60 years on average, were primarily from Allegheny County, Pa., and had neuropathy either suspected to be hereditary or of unknown etiology.

Among the 19% of patients (n = 16) who tested positive for a known pathogenic mutation, half had Charcot-Marie-Tooth disease type 1A (CMT1A). Two patients – 13% of those with pathogenic variants – had hereditary neuropathy with liability to pressure palsies, and two had CMT1X. The remaining four patients had CMT1B, CMT2B1, CMT2E, and hereditary sensory and autonomic neuropathy mutations.

Another 4% of the overall patient sample (n = 3) had likely pathogenic mutations in genes associated with CMT2S, CMT4C and CMT4F. A third of the patients (32%) tested negative for the full NGS panel, and, comprising the largest proportion of patients, 46% had variants of unknown significance.

“The high occurrence of variants of unknown significance has uncertain significance but some variations may represent unrecognized pathogenic mutations,” the authors noted.

They identified 81 of these variants, with the DST, PLEKHG5, and SPG11 genes most commonly affected, each found in six patients. Four patients had a variant in the next most commonly affected gene, SBF2. The following variants occurred in three people each: BICD2, NEFL3, PRX, SCN11A, SCN9A, SLC52A2, and WNK1.

Among the 73 patients who underwent electrodiagnostic testing, 44 had sporadic axonal neuropathy, 17 had sporadic demyelinating neuropathy, and 11 had mixed neuropathies; the 1 remaining patient was not accounted for. Positive genetic testing occurred in a third (32%) of those with familial neuropathy (n = 28) and in 12% of those with sporadic neuropathy (n = 57).

No external funding was noted, and the authors had no disclosures.

SOURCE: Zivkovic S et al. AANEM 2019. Abstract 160. Targeted genetic testing in the evaluation of neuropathy .

AUSTIN, TEX. – Patients with peripheral neuropathy may benefit from genetic testing to determine of the cause of their neuropathy even if they do not have a family history of the condition, according to new research.

The same research identified more than 80 genetic variants in patients with neuropathy who lacked any other known genetic mutations, potentially representing not-yet-identified pathogenic mutations.

Sasa Zivkovic, MD, PhD, of the University of Pittsburgh Medical Center (UPMC), and associates shared a poster of their findings at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

The researchers conducted next-generation sequencing (NGS) on 85 adult patients with peripheral neuropathy at the UPMC Neuromuscular Clinic during May 2017–Feb. 2019. The targeted NGS panel included 70 genes. The patients, aged 60 years on average, were primarily from Allegheny County, Pa., and had neuropathy either suspected to be hereditary or of unknown etiology.

Among the 19% of patients (n = 16) who tested positive for a known pathogenic mutation, half had Charcot-Marie-Tooth disease type 1A (CMT1A). Two patients – 13% of those with pathogenic variants – had hereditary neuropathy with liability to pressure palsies, and two had CMT1X. The remaining four patients had CMT1B, CMT2B1, CMT2E, and hereditary sensory and autonomic neuropathy mutations.

Another 4% of the overall patient sample (n = 3) had likely pathogenic mutations in genes associated with CMT2S, CMT4C and CMT4F. A third of the patients (32%) tested negative for the full NGS panel, and, comprising the largest proportion of patients, 46% had variants of unknown significance.

“The high occurrence of variants of unknown significance has uncertain significance but some variations may represent unrecognized pathogenic mutations,” the authors noted.

They identified 81 of these variants, with the DST, PLEKHG5, and SPG11 genes most commonly affected, each found in six patients. Four patients had a variant in the next most commonly affected gene, SBF2. The following variants occurred in three people each: BICD2, NEFL3, PRX, SCN11A, SCN9A, SLC52A2, and WNK1.

Among the 73 patients who underwent electrodiagnostic testing, 44 had sporadic axonal neuropathy, 17 had sporadic demyelinating neuropathy, and 11 had mixed neuropathies; the 1 remaining patient was not accounted for. Positive genetic testing occurred in a third (32%) of those with familial neuropathy (n = 28) and in 12% of those with sporadic neuropathy (n = 57).

No external funding was noted, and the authors had no disclosures.

SOURCE: Zivkovic S et al. AANEM 2019. Abstract 160. Targeted genetic testing in the evaluation of neuropathy .

AUSTIN, TEX. – Patients with peripheral neuropathy may benefit from genetic testing to determine of the cause of their neuropathy even if they do not have a family history of the condition, according to new research.

The same research identified more than 80 genetic variants in patients with neuropathy who lacked any other known genetic mutations, potentially representing not-yet-identified pathogenic mutations.

Sasa Zivkovic, MD, PhD, of the University of Pittsburgh Medical Center (UPMC), and associates shared a poster of their findings at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

The researchers conducted next-generation sequencing (NGS) on 85 adult patients with peripheral neuropathy at the UPMC Neuromuscular Clinic during May 2017–Feb. 2019. The targeted NGS panel included 70 genes. The patients, aged 60 years on average, were primarily from Allegheny County, Pa., and had neuropathy either suspected to be hereditary or of unknown etiology.

Among the 19% of patients (n = 16) who tested positive for a known pathogenic mutation, half had Charcot-Marie-Tooth disease type 1A (CMT1A). Two patients – 13% of those with pathogenic variants – had hereditary neuropathy with liability to pressure palsies, and two had CMT1X. The remaining four patients had CMT1B, CMT2B1, CMT2E, and hereditary sensory and autonomic neuropathy mutations.

Another 4% of the overall patient sample (n = 3) had likely pathogenic mutations in genes associated with CMT2S, CMT4C and CMT4F. A third of the patients (32%) tested negative for the full NGS panel, and, comprising the largest proportion of patients, 46% had variants of unknown significance.

“The high occurrence of variants of unknown significance has uncertain significance but some variations may represent unrecognized pathogenic mutations,” the authors noted.

They identified 81 of these variants, with the DST, PLEKHG5, and SPG11 genes most commonly affected, each found in six patients. Four patients had a variant in the next most commonly affected gene, SBF2. The following variants occurred in three people each: BICD2, NEFL3, PRX, SCN11A, SCN9A, SLC52A2, and WNK1.

Among the 73 patients who underwent electrodiagnostic testing, 44 had sporadic axonal neuropathy, 17 had sporadic demyelinating neuropathy, and 11 had mixed neuropathies; the 1 remaining patient was not accounted for. Positive genetic testing occurred in a third (32%) of those with familial neuropathy (n = 28) and in 12% of those with sporadic neuropathy (n = 57).

No external funding was noted, and the authors had no disclosures.

SOURCE: Zivkovic S et al. AANEM 2019. Abstract 160. Targeted genetic testing in the evaluation of neuropathy .

AUSTIN, TEX. – Dichlorphenamide continues to reduce attacks from primary periodic paralysis (PPP) through 1 year with mild or moderate paresthesia and cognition-related adverse events, according to new research.

“These adverse events rarely resulted in discontinuation from the study and were sometimes managed by dichlorphenamide dose reductions,” concluded Nicholas E. Johnson, MD, of Virginia Commonwealth University, Richmond, and colleagues. “Reduction in dose was frequently associated with resolution of these events, suggesting a potential intervention to hasten resolution.” Dr. Johnson presented the findings in an abstract at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

Dichlorphenamide (Keveyis) was approved by the Food and Drug Administration in 2015 for treating primary hyperkalemic and hypokalemic periodic paralysis and similar variants. The original hyperkalemic/hypokalemic PPP trial was a phase 3 randomized, double-blind, placebo-controlled trial that lasted 9 weeks and assessed the efficacy of dichlorphenamide in reducing PPP attacks and its adverse events. In the dichlorphenamide group, 47% experienced paresthesia, compared with 14% in the placebo group, and 19% experienced cognitive disorder, compared with 7% in the placebo.

In a 52-week open-label extension, participants who had been receiving the placebo switched to receiving 50 mg of dichlorphenamide twice daily. The intervention group continued with the dose they had been receiving when the 9-week double-blind phase ended. (During the initial intervention, they took either 50 mg twice daily or the dose they had at baseline for those taking it before the study began.)

The researchers then tracked rates of attacks and their severity over the next year – through week 61 after baseline – to compare these endpoints both within the intervention groups and between them.

Among the 63 predominantly white (84.1%) male (61.9%) adults who began the trial, 36 received dichlorphenamide and 27 received placebo. Just over two-thirds (68.3%) had hypokalemic PPP. Among the 47 patients (74.6%) who completed the open-label extension phase, 26 had been in the original dichlorphenamide group and 21 had been in the placebo group.

The median weekly attack rate in the dichlorphenamide group dropped from 1.75 at baseline to 0.06 at week 61 (median decrease 1.00, 93.8%; P less than .0001). In the placebo group that switched over to dichlorphenamide at week 9, the median weekly attack rate dropped from 3.00 at baseline to 0.25 at week 61 (median decrease 0.63, 75%; P = .01).

The median attack rate weighted for severity in the dichlorphenamide group dropped from 2.25 at baseline to 0.06 at week 61 (median decrease 2.25, 97.1%; P less than .0001). In the placebo group, it dropped from 5.88 to 0.50 (median decrease 1.69, 80.8%; P = .01).

No significant difference in median weekly attack rates and severity-weighted attack rates was found between the intervention groups through week 61.

Across all patients during the extension, 39.7% patients experienced at least one paresthesia adverse event, none of which were determined to be severe and resulting in one discontinuation.

A quarter of the participants (25.4%) experienced at least one cognition-related adverse event, and four patients (6.3%) discontinued because of these side effects. Most (14.3%) were mild with 7.9% reporting moderate and 3.2% reporting severe effects.

Dr. Johnson has received research support from or consulted with a variety of pharmaceutical companies including Strongbridge Biopharma, the manufacturer of the drug. Other authors consulted for several pharmaceutical companies, and one author is an employee of Strongbridge Biopharma.
 

SOURCE: Johnson NE et al. AANEM 2019. Abstract 102. Long-term efficacy and adverse event characterization of dichlorphenamide for the treatment of primary periodic paralysis.

AUSTIN, TEX. – Dichlorphenamide continues to reduce attacks from primary periodic paralysis (PPP) through 1 year with mild or moderate paresthesia and cognition-related adverse events, according to new research.

“These adverse events rarely resulted in discontinuation from the study and were sometimes managed by dichlorphenamide dose reductions,” concluded Nicholas E. Johnson, MD, of Virginia Commonwealth University, Richmond, and colleagues. “Reduction in dose was frequently associated with resolution of these events, suggesting a potential intervention to hasten resolution.” Dr. Johnson presented the findings in an abstract at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

Dichlorphenamide (Keveyis) was approved by the Food and Drug Administration in 2015 for treating primary hyperkalemic and hypokalemic periodic paralysis and similar variants. The original hyperkalemic/hypokalemic PPP trial was a phase 3 randomized, double-blind, placebo-controlled trial that lasted 9 weeks and assessed the efficacy of dichlorphenamide in reducing PPP attacks and its adverse events. In the dichlorphenamide group, 47% experienced paresthesia, compared with 14% in the placebo group, and 19% experienced cognitive disorder, compared with 7% in the placebo.

In a 52-week open-label extension, participants who had been receiving the placebo switched to receiving 50 mg of dichlorphenamide twice daily. The intervention group continued with the dose they had been receiving when the 9-week double-blind phase ended. (During the initial intervention, they took either 50 mg twice daily or the dose they had at baseline for those taking it before the study began.)

The researchers then tracked rates of attacks and their severity over the next year – through week 61 after baseline – to compare these endpoints both within the intervention groups and between them.

Among the 63 predominantly white (84.1%) male (61.9%) adults who began the trial, 36 received dichlorphenamide and 27 received placebo. Just over two-thirds (68.3%) had hypokalemic PPP. Among the 47 patients (74.6%) who completed the open-label extension phase, 26 had been in the original dichlorphenamide group and 21 had been in the placebo group.

The median weekly attack rate in the dichlorphenamide group dropped from 1.75 at baseline to 0.06 at week 61 (median decrease 1.00, 93.8%; P less than .0001). In the placebo group that switched over to dichlorphenamide at week 9, the median weekly attack rate dropped from 3.00 at baseline to 0.25 at week 61 (median decrease 0.63, 75%; P = .01).

The median attack rate weighted for severity in the dichlorphenamide group dropped from 2.25 at baseline to 0.06 at week 61 (median decrease 2.25, 97.1%; P less than .0001). In the placebo group, it dropped from 5.88 to 0.50 (median decrease 1.69, 80.8%; P = .01).

No significant difference in median weekly attack rates and severity-weighted attack rates was found between the intervention groups through week 61.

Across all patients during the extension, 39.7% patients experienced at least one paresthesia adverse event, none of which were determined to be severe and resulting in one discontinuation.

A quarter of the participants (25.4%) experienced at least one cognition-related adverse event, and four patients (6.3%) discontinued because of these side effects. Most (14.3%) were mild with 7.9% reporting moderate and 3.2% reporting severe effects.

Dr. Johnson has received research support from or consulted with a variety of pharmaceutical companies including Strongbridge Biopharma, the manufacturer of the drug. Other authors consulted for several pharmaceutical companies, and one author is an employee of Strongbridge Biopharma.
 

SOURCE: Johnson NE et al. AANEM 2019. Abstract 102. Long-term efficacy and adverse event characterization of dichlorphenamide for the treatment of primary periodic paralysis.

AUSTIN, TEX. – Dichlorphenamide continues to reduce attacks from primary periodic paralysis (PPP) through 1 year with mild or moderate paresthesia and cognition-related adverse events, according to new research.

“These adverse events rarely resulted in discontinuation from the study and were sometimes managed by dichlorphenamide dose reductions,” concluded Nicholas E. Johnson, MD, of Virginia Commonwealth University, Richmond, and colleagues. “Reduction in dose was frequently associated with resolution of these events, suggesting a potential intervention to hasten resolution.” Dr. Johnson presented the findings in an abstract at the annual meeting of the American Association for Neuromuscular and Electrodiagnostic Medicine.

Dichlorphenamide (Keveyis) was approved by the Food and Drug Administration in 2015 for treating primary hyperkalemic and hypokalemic periodic paralysis and similar variants. The original hyperkalemic/hypokalemic PPP trial was a phase 3 randomized, double-blind, placebo-controlled trial that lasted 9 weeks and assessed the efficacy of dichlorphenamide in reducing PPP attacks and its adverse events. In the dichlorphenamide group, 47% experienced paresthesia, compared with 14% in the placebo group, and 19% experienced cognitive disorder, compared with 7% in the placebo.

In a 52-week open-label extension, participants who had been receiving the placebo switched to receiving 50 mg of dichlorphenamide twice daily. The intervention group continued with the dose they had been receiving when the 9-week double-blind phase ended. (During the initial intervention, they took either 50 mg twice daily or the dose they had at baseline for those taking it before the study began.)

The researchers then tracked rates of attacks and their severity over the next year – through week 61 after baseline – to compare these endpoints both within the intervention groups and between them.

Among the 63 predominantly white (84.1%) male (61.9%) adults who began the trial, 36 received dichlorphenamide and 27 received placebo. Just over two-thirds (68.3%) had hypokalemic PPP. Among the 47 patients (74.6%) who completed the open-label extension phase, 26 had been in the original dichlorphenamide group and 21 had been in the placebo group.

The median weekly attack rate in the dichlorphenamide group dropped from 1.75 at baseline to 0.06 at week 61 (median decrease 1.00, 93.8%; P less than .0001). In the placebo group that switched over to dichlorphenamide at week 9, the median weekly attack rate dropped from 3.00 at baseline to 0.25 at week 61 (median decrease 0.63, 75%; P = .01).

The median attack rate weighted for severity in the dichlorphenamide group dropped from 2.25 at baseline to 0.06 at week 61 (median decrease 2.25, 97.1%; P less than .0001). In the placebo group, it dropped from 5.88 to 0.50 (median decrease 1.69, 80.8%; P = .01).

No significant difference in median weekly attack rates and severity-weighted attack rates was found between the intervention groups through week 61.

Across all patients during the extension, 39.7% patients experienced at least one paresthesia adverse event, none of which were determined to be severe and resulting in one discontinuation.

A quarter of the participants (25.4%) experienced at least one cognition-related adverse event, and four patients (6.3%) discontinued because of these side effects. Most (14.3%) were mild with 7.9% reporting moderate and 3.2% reporting severe effects.

Dr. Johnson has received research support from or consulted with a variety of pharmaceutical companies including Strongbridge Biopharma, the manufacturer of the drug. Other authors consulted for several pharmaceutical companies, and one author is an employee of Strongbridge Biopharma.
 

SOURCE: Johnson NE et al. AANEM 2019. Abstract 102. Long-term efficacy and adverse event characterization of dichlorphenamide for the treatment of primary periodic paralysis.

AUSTIN, TEX. – Patients with Charcot-Marie-Tooth disease (CMT) receive a range of supportive care that includes physical therapy, surgery, medications, orthoses, and walking aids, according to patient-reported data presented at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine. Patients describe approaches to CMT management that are broadly consistent with guidelines, researchers said.

“The range of different CMT treatments was wide,” reported Tjalf Ziemssen, MD, PhD, a researcher at Technische Universität Dresden in Germany, and colleagues. “Of note, high proportions of respondents had received pain medication, and a relatively high number had also visited pain specialists. These results indicate that pain may have a substantial impact on people with CMT.”

The data also suggest that “lower-limb problems and mobility issues have a considerable impact on people with CMT,” they said.

CMT is a rare, progressive neuropathy that leads to distal muscle weakness, muscle atrophy, and sensory loss. There is no cure, and patients rely on supportive care. Until recently, few studies have assessed the impact of CMT on patients’ lives.

An ongoing, international, 2-year observational study is collecting data from adults with CMT. Patients report data via an app called CMT & Me.

To examine patient-reported treatment patterns and care standards for CMT in the United States and the United Kingdom, Dr. Ziemssen and colleagues analyzed data through Aug. 5, 2019, about 9.5 months into the study. Their interim analysis included data from 439 patients, including 222 patients in the United Kingdom and 217 in the United States.

More than 70% of participants visit a family doctor each year, and a similar proportion visit a neurologist. About 40% visit physical therapists, orthotists, or podiatrists. Other health care professionals seen by patients include occupational therapists (20%), orthopedic surgeons (nearly 20%), and pain specialists (about 15%).

About 70% of participants had received rehabilitation therapy such as physical therapy or occupational therapy, and about 70% had used medications, most frequently nonopioid analgesics (about 50%) and antidepressants (about 30%).

More than 80% used orthoses or walking aids, most commonly ankle or leg braces, insoles, or walking sticks.

In addition, about half of respondents had undergone a surgery for CMT. The most common procedures were osteotomy, hammertoe correction, and plantar fascia release.

Together, patients saw about a dozen types of health care professionals. “Small proportions of participants had visited each professional, which suggests that the care requirements of CMT patients are varied,” the researchers said.

The study was sponsored by Pharnext. Dr. Ziemssen and coauthors received compensation for participating in the study. Other coauthors are employees of Pharnext or Vitaccess, the company that developed the app used in the study.

[email protected]

SOURCE: Ziemssen T et al. AANEM 2019. Abstract 83. Treatment of Charcot-Marie-Tooth Disease in the United Kingdom and United States.

AUSTIN, TEX. – Patients with Charcot-Marie-Tooth disease (CMT) receive a range of supportive care that includes physical therapy, surgery, medications, orthoses, and walking aids, according to patient-reported data presented at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine. Patients describe approaches to CMT management that are broadly consistent with guidelines, researchers said.

“The range of different CMT treatments was wide,” reported Tjalf Ziemssen, MD, PhD, a researcher at Technische Universität Dresden in Germany, and colleagues. “Of note, high proportions of respondents had received pain medication, and a relatively high number had also visited pain specialists. These results indicate that pain may have a substantial impact on people with CMT.”

The data also suggest that “lower-limb problems and mobility issues have a considerable impact on people with CMT,” they said.

CMT is a rare, progressive neuropathy that leads to distal muscle weakness, muscle atrophy, and sensory loss. There is no cure, and patients rely on supportive care. Until recently, few studies have assessed the impact of CMT on patients’ lives.

An ongoing, international, 2-year observational study is collecting data from adults with CMT. Patients report data via an app called CMT & Me.

To examine patient-reported treatment patterns and care standards for CMT in the United States and the United Kingdom, Dr. Ziemssen and colleagues analyzed data through Aug. 5, 2019, about 9.5 months into the study. Their interim analysis included data from 439 patients, including 222 patients in the United Kingdom and 217 in the United States.

More than 70% of participants visit a family doctor each year, and a similar proportion visit a neurologist. About 40% visit physical therapists, orthotists, or podiatrists. Other health care professionals seen by patients include occupational therapists (20%), orthopedic surgeons (nearly 20%), and pain specialists (about 15%).

About 70% of participants had received rehabilitation therapy such as physical therapy or occupational therapy, and about 70% had used medications, most frequently nonopioid analgesics (about 50%) and antidepressants (about 30%).

More than 80% used orthoses or walking aids, most commonly ankle or leg braces, insoles, or walking sticks.

In addition, about half of respondents had undergone a surgery for CMT. The most common procedures were osteotomy, hammertoe correction, and plantar fascia release.

Together, patients saw about a dozen types of health care professionals. “Small proportions of participants had visited each professional, which suggests that the care requirements of CMT patients are varied,” the researchers said.

The study was sponsored by Pharnext. Dr. Ziemssen and coauthors received compensation for participating in the study. Other coauthors are employees of Pharnext or Vitaccess, the company that developed the app used in the study.

[email protected]

SOURCE: Ziemssen T et al. AANEM 2019. Abstract 83. Treatment of Charcot-Marie-Tooth Disease in the United Kingdom and United States.

AUSTIN, TEX. – Patients with Charcot-Marie-Tooth disease (CMT) receive a range of supportive care that includes physical therapy, surgery, medications, orthoses, and walking aids, according to patient-reported data presented at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine. Patients describe approaches to CMT management that are broadly consistent with guidelines, researchers said.

“The range of different CMT treatments was wide,” reported Tjalf Ziemssen, MD, PhD, a researcher at Technische Universität Dresden in Germany, and colleagues. “Of note, high proportions of respondents had received pain medication, and a relatively high number had also visited pain specialists. These results indicate that pain may have a substantial impact on people with CMT.”

The data also suggest that “lower-limb problems and mobility issues have a considerable impact on people with CMT,” they said.

CMT is a rare, progressive neuropathy that leads to distal muscle weakness, muscle atrophy, and sensory loss. There is no cure, and patients rely on supportive care. Until recently, few studies have assessed the impact of CMT on patients’ lives.

An ongoing, international, 2-year observational study is collecting data from adults with CMT. Patients report data via an app called CMT & Me.

To examine patient-reported treatment patterns and care standards for CMT in the United States and the United Kingdom, Dr. Ziemssen and colleagues analyzed data through Aug. 5, 2019, about 9.5 months into the study. Their interim analysis included data from 439 patients, including 222 patients in the United Kingdom and 217 in the United States.

More than 70% of participants visit a family doctor each year, and a similar proportion visit a neurologist. About 40% visit physical therapists, orthotists, or podiatrists. Other health care professionals seen by patients include occupational therapists (20%), orthopedic surgeons (nearly 20%), and pain specialists (about 15%).

About 70% of participants had received rehabilitation therapy such as physical therapy or occupational therapy, and about 70% had used medications, most frequently nonopioid analgesics (about 50%) and antidepressants (about 30%).

More than 80% used orthoses or walking aids, most commonly ankle or leg braces, insoles, or walking sticks.

In addition, about half of respondents had undergone a surgery for CMT. The most common procedures were osteotomy, hammertoe correction, and plantar fascia release.

Together, patients saw about a dozen types of health care professionals. “Small proportions of participants had visited each professional, which suggests that the care requirements of CMT patients are varied,” the researchers said.

The study was sponsored by Pharnext. Dr. Ziemssen and coauthors received compensation for participating in the study. Other coauthors are employees of Pharnext or Vitaccess, the company that developed the app used in the study.

[email protected]

SOURCE: Ziemssen T et al. AANEM 2019. Abstract 83. Treatment of Charcot-Marie-Tooth Disease in the United Kingdom and United States.

AUSTIN – Lack of upper motor neuron signs on examination, presence of sensory symptoms, and absence of tongue fasciculations are common causes of amyotrophic lateral sclerosis (ALS) misdiagnosis, according to an investigation presented at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine.

designer491/Thinkstock

Because its initial presenting symptoms vary, ALS can be difficult for clinicians to diagnose. A diagnostic error may prompt clinicians and patients to pursue ineffective and potentially harmful medical or surgical interventions. Research suggests that surgery, for example, hastens the progression of ALS.

Catherine Rodriguez, a medical student at University of Missouri in Columbia, and colleagues conducted a study to identify the clinical factors and types of cognitive errors that can result in misdiagnosis of ALS. The researchers analyzed electronic medical records of 88 patients with a diagnosis of ALS who were receiving treatment at the University of Missouri Hospital during 2011-2017 with at least 1 year of follow-up. They collected demographic information and clinical characteristics (e.g., ALS Functional Rating Scale and site of symptom onset) for each patient. If a patient received an incorrect diagnosis, Ms. Rodriguez and colleagues recorded the number of physicians he or she had seen, the incorrect diagnosis, the treatment, the type of diagnostic error, the clinical factors contributing to the misdiagnosis, and the type of physician who gave the incorrect diagnosis.

The investigators classed diagnostic errors according to the four categories of cognitive bias of the Patient Safety Network. The categories are availability heuristic (i.e., the diagnosis of a current patient is biased by the clinician’s experience with previous cases), anchoring heuristic (i.e., relying on the initial impression despite the emergence of evidence that may contradict it), framing effects (i.e., subtle cues and collateral information bias the diagnosis), and blind obedience (i.e., undue reliance on test results or expert opinion). Ms. Rodriguez and colleagues used Fisher’s exact test to perform a statistical analysis of the data.

Thirty-four (39%) of the 88 patients were female, and the populations average age was about 60 years. Eighty patients (91%) were white, six (7%) were black, and two (2%) were Hispanic. Twenty patients (23%) received an incorrect diagnosis. Common incorrect diagnoses included spinal abnormality, Bell’s palsy, myasthenia gravis, ulnar neuropathy, autoimmune motor neuropathy, and stroke.

The investigators observed significant differences in the reasons for misdiagnosis, depending on patient characteristics. Veterans were misdiagnosed because of the availability heuristic, while nonveterans were misdiagnosed because of the anchoring heuristic. Lower-limb onset was most commonly misdiagnosed because of the anchoring heuristic. Bulbar onset was most commonly misdiagnosed because of the availability heuristic. Surgical intervention was the most common treatment for an incorrect diagnosis.

The data serve as a reminder of the prevalence of cognitive biases, said Ms. Rodriguez. “Common things are common, so we tend to stick with those [diagnoses]. Especially with ALS, nobody wants to give anyone that diagnosis.” Clinicians should “recognize that incorrect diagnoses have equally bad outcomes for those patients,” she concluded.

The study was supported by a University of Missouri School of Medicine Summer Research Fellowship Program.

[email protected]

SOURCE: Rodriguez C et al. AANEM 2019. Abstract 10. Diagnostic errors and the implications for amyotrophic lateral sclerosis patients.

AUSTIN – Lack of upper motor neuron signs on examination, presence of sensory symptoms, and absence of tongue fasciculations are common causes of amyotrophic lateral sclerosis (ALS) misdiagnosis, according to an investigation presented at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine.

designer491/Thinkstock

Because its initial presenting symptoms vary, ALS can be difficult for clinicians to diagnose. A diagnostic error may prompt clinicians and patients to pursue ineffective and potentially harmful medical or surgical interventions. Research suggests that surgery, for example, hastens the progression of ALS.

Catherine Rodriguez, a medical student at University of Missouri in Columbia, and colleagues conducted a study to identify the clinical factors and types of cognitive errors that can result in misdiagnosis of ALS. The researchers analyzed electronic medical records of 88 patients with a diagnosis of ALS who were receiving treatment at the University of Missouri Hospital during 2011-2017 with at least 1 year of follow-up. They collected demographic information and clinical characteristics (e.g., ALS Functional Rating Scale and site of symptom onset) for each patient. If a patient received an incorrect diagnosis, Ms. Rodriguez and colleagues recorded the number of physicians he or she had seen, the incorrect diagnosis, the treatment, the type of diagnostic error, the clinical factors contributing to the misdiagnosis, and the type of physician who gave the incorrect diagnosis.

The investigators classed diagnostic errors according to the four categories of cognitive bias of the Patient Safety Network. The categories are availability heuristic (i.e., the diagnosis of a current patient is biased by the clinician’s experience with previous cases), anchoring heuristic (i.e., relying on the initial impression despite the emergence of evidence that may contradict it), framing effects (i.e., subtle cues and collateral information bias the diagnosis), and blind obedience (i.e., undue reliance on test results or expert opinion). Ms. Rodriguez and colleagues used Fisher’s exact test to perform a statistical analysis of the data.

Thirty-four (39%) of the 88 patients were female, and the populations average age was about 60 years. Eighty patients (91%) were white, six (7%) were black, and two (2%) were Hispanic. Twenty patients (23%) received an incorrect diagnosis. Common incorrect diagnoses included spinal abnormality, Bell’s palsy, myasthenia gravis, ulnar neuropathy, autoimmune motor neuropathy, and stroke.

The investigators observed significant differences in the reasons for misdiagnosis, depending on patient characteristics. Veterans were misdiagnosed because of the availability heuristic, while nonveterans were misdiagnosed because of the anchoring heuristic. Lower-limb onset was most commonly misdiagnosed because of the anchoring heuristic. Bulbar onset was most commonly misdiagnosed because of the availability heuristic. Surgical intervention was the most common treatment for an incorrect diagnosis.

The data serve as a reminder of the prevalence of cognitive biases, said Ms. Rodriguez. “Common things are common, so we tend to stick with those [diagnoses]. Especially with ALS, nobody wants to give anyone that diagnosis.” Clinicians should “recognize that incorrect diagnoses have equally bad outcomes for those patients,” she concluded.

The study was supported by a University of Missouri School of Medicine Summer Research Fellowship Program.

[email protected]

SOURCE: Rodriguez C et al. AANEM 2019. Abstract 10. Diagnostic errors and the implications for amyotrophic lateral sclerosis patients.

AUSTIN – Lack of upper motor neuron signs on examination, presence of sensory symptoms, and absence of tongue fasciculations are common causes of amyotrophic lateral sclerosis (ALS) misdiagnosis, according to an investigation presented at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine.

designer491/Thinkstock

Because its initial presenting symptoms vary, ALS can be difficult for clinicians to diagnose. A diagnostic error may prompt clinicians and patients to pursue ineffective and potentially harmful medical or surgical interventions. Research suggests that surgery, for example, hastens the progression of ALS.

Catherine Rodriguez, a medical student at University of Missouri in Columbia, and colleagues conducted a study to identify the clinical factors and types of cognitive errors that can result in misdiagnosis of ALS. The researchers analyzed electronic medical records of 88 patients with a diagnosis of ALS who were receiving treatment at the University of Missouri Hospital during 2011-2017 with at least 1 year of follow-up. They collected demographic information and clinical characteristics (e.g., ALS Functional Rating Scale and site of symptom onset) for each patient. If a patient received an incorrect diagnosis, Ms. Rodriguez and colleagues recorded the number of physicians he or she had seen, the incorrect diagnosis, the treatment, the type of diagnostic error, the clinical factors contributing to the misdiagnosis, and the type of physician who gave the incorrect diagnosis.

The investigators classed diagnostic errors according to the four categories of cognitive bias of the Patient Safety Network. The categories are availability heuristic (i.e., the diagnosis of a current patient is biased by the clinician’s experience with previous cases), anchoring heuristic (i.e., relying on the initial impression despite the emergence of evidence that may contradict it), framing effects (i.e., subtle cues and collateral information bias the diagnosis), and blind obedience (i.e., undue reliance on test results or expert opinion). Ms. Rodriguez and colleagues used Fisher’s exact test to perform a statistical analysis of the data.

Thirty-four (39%) of the 88 patients were female, and the populations average age was about 60 years. Eighty patients (91%) were white, six (7%) were black, and two (2%) were Hispanic. Twenty patients (23%) received an incorrect diagnosis. Common incorrect diagnoses included spinal abnormality, Bell’s palsy, myasthenia gravis, ulnar neuropathy, autoimmune motor neuropathy, and stroke.

The investigators observed significant differences in the reasons for misdiagnosis, depending on patient characteristics. Veterans were misdiagnosed because of the availability heuristic, while nonveterans were misdiagnosed because of the anchoring heuristic. Lower-limb onset was most commonly misdiagnosed because of the anchoring heuristic. Bulbar onset was most commonly misdiagnosed because of the availability heuristic. Surgical intervention was the most common treatment for an incorrect diagnosis.

The data serve as a reminder of the prevalence of cognitive biases, said Ms. Rodriguez. “Common things are common, so we tend to stick with those [diagnoses]. Especially with ALS, nobody wants to give anyone that diagnosis.” Clinicians should “recognize that incorrect diagnoses have equally bad outcomes for those patients,” she concluded.

The study was supported by a University of Missouri School of Medicine Summer Research Fellowship Program.

[email protected]

SOURCE: Rodriguez C et al. AANEM 2019. Abstract 10. Diagnostic errors and the implications for amyotrophic lateral sclerosis patients.

AUSTIN, TEX. – Patients with suspected myasthenia gravis are more likely to have positive repetitive nerve stimulation (RNS) findings if they undergo testing in an inpatient setting, are seropositive, or are classified as Myasthenia Gravis Foundation of America (MGFA) Class III or higher, according to research presented at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine.

Low-frequency RNS is a common test that neurologists perform to evaluate a patient for myasthenia gravis. The effects of various clinical factors on the diagnostic yield of this test are unknown, however.

Myasthenia gravis is “mostly a clinical diagnosis,” study first author Tingting Hua, a medical student at the University of Missouri in Columbia, said in an interview. “RNS is just one of the helpful diagnostic tests for it. If we can find out in what kind of populations of patients this test is more helpful, maybe that would help cut down unnecessary tests in patients for whom it’s not necessarily helpful.”

Ms. Hua and her colleagues conducted research to assess the effects of clinical, serologic, and demographic factors on the diagnostic yield of RNS. They retrospectively analyzed patients with an established diagnosis of myasthenia gravis and at least 1 year of follow-up. The variables that the investigators examined were demographic characteristics, MGFA class, RNS study results, antibody test results, thymoma status, and treatments received.

Ms. Hua and her colleagues included 65 patients in their analysis. Thirty-one patients were female. Fifty-five patients were white, eight were black, and two were categorized as “unknown.” Of this population, 32 patients (49.2%) were in MGFA Class I, 14 (21.5%) were in MGFA Class IIa, 13 (20.0%) were in MGFA Class IIb, and the remaining 6 (9.2%) were in MGFA Classes IIIa through V. Twenty-seven patients (42%) had positive RNS studies. Twenty-one patients (32%) were seropositive for myasthenia gravis antibodies.

Eleven patients underwent RNS in an inpatient setting, and 54 were tested in an outpatient setting. Acetylcholine receptor (AChR) binding antibody titer ranged from 0.12 nmol/L to 118 nmol/L. The RNS results were significantly more likely to be positive for seropositive patients, compared with seronegative patients. Patients with MGFA Class III or higher also had higher likelihood of positive RNS results, compared with patients in lower classes. Finally, the diagnostic yield was highest for patients with MGFA Class III or higher who were tested in an inpatient setting.

The study was supported by a Missouri School of Medicine Summer Research Fellowship.

[email protected]

SOURCE: Hua T et al. AANEM 2019, Abstract 9.

AUSTIN, TEX. – Patients with suspected myasthenia gravis are more likely to have positive repetitive nerve stimulation (RNS) findings if they undergo testing in an inpatient setting, are seropositive, or are classified as Myasthenia Gravis Foundation of America (MGFA) Class III or higher, according to research presented at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine.

Low-frequency RNS is a common test that neurologists perform to evaluate a patient for myasthenia gravis. The effects of various clinical factors on the diagnostic yield of this test are unknown, however.

Myasthenia gravis is “mostly a clinical diagnosis,” study first author Tingting Hua, a medical student at the University of Missouri in Columbia, said in an interview. “RNS is just one of the helpful diagnostic tests for it. If we can find out in what kind of populations of patients this test is more helpful, maybe that would help cut down unnecessary tests in patients for whom it’s not necessarily helpful.”

Ms. Hua and her colleagues conducted research to assess the effects of clinical, serologic, and demographic factors on the diagnostic yield of RNS. They retrospectively analyzed patients with an established diagnosis of myasthenia gravis and at least 1 year of follow-up. The variables that the investigators examined were demographic characteristics, MGFA class, RNS study results, antibody test results, thymoma status, and treatments received.

Ms. Hua and her colleagues included 65 patients in their analysis. Thirty-one patients were female. Fifty-five patients were white, eight were black, and two were categorized as “unknown.” Of this population, 32 patients (49.2%) were in MGFA Class I, 14 (21.5%) were in MGFA Class IIa, 13 (20.0%) were in MGFA Class IIb, and the remaining 6 (9.2%) were in MGFA Classes IIIa through V. Twenty-seven patients (42%) had positive RNS studies. Twenty-one patients (32%) were seropositive for myasthenia gravis antibodies.

Eleven patients underwent RNS in an inpatient setting, and 54 were tested in an outpatient setting. Acetylcholine receptor (AChR) binding antibody titer ranged from 0.12 nmol/L to 118 nmol/L. The RNS results were significantly more likely to be positive for seropositive patients, compared with seronegative patients. Patients with MGFA Class III or higher also had higher likelihood of positive RNS results, compared with patients in lower classes. Finally, the diagnostic yield was highest for patients with MGFA Class III or higher who were tested in an inpatient setting.

The study was supported by a Missouri School of Medicine Summer Research Fellowship.

[email protected]

SOURCE: Hua T et al. AANEM 2019, Abstract 9.

AUSTIN, TEX. – Patients with suspected myasthenia gravis are more likely to have positive repetitive nerve stimulation (RNS) findings if they undergo testing in an inpatient setting, are seropositive, or are classified as Myasthenia Gravis Foundation of America (MGFA) Class III or higher, according to research presented at the annual meeting of the American Association of Neuromuscular and Electrodiagnostic Medicine.

Low-frequency RNS is a common test that neurologists perform to evaluate a patient for myasthenia gravis. The effects of various clinical factors on the diagnostic yield of this test are unknown, however.

Myasthenia gravis is “mostly a clinical diagnosis,” study first author Tingting Hua, a medical student at the University of Missouri in Columbia, said in an interview. “RNS is just one of the helpful diagnostic tests for it. If we can find out in what kind of populations of patients this test is more helpful, maybe that would help cut down unnecessary tests in patients for whom it’s not necessarily helpful.”

Ms. Hua and her colleagues conducted research to assess the effects of clinical, serologic, and demographic factors on the diagnostic yield of RNS. They retrospectively analyzed patients with an established diagnosis of myasthenia gravis and at least 1 year of follow-up. The variables that the investigators examined were demographic characteristics, MGFA class, RNS study results, antibody test results, thymoma status, and treatments received.

Ms. Hua and her colleagues included 65 patients in their analysis. Thirty-one patients were female. Fifty-five patients were white, eight were black, and two were categorized as “unknown.” Of this population, 32 patients (49.2%) were in MGFA Class I, 14 (21.5%) were in MGFA Class IIa, 13 (20.0%) were in MGFA Class IIb, and the remaining 6 (9.2%) were in MGFA Classes IIIa through V. Twenty-seven patients (42%) had positive RNS studies. Twenty-one patients (32%) were seropositive for myasthenia gravis antibodies.

Eleven patients underwent RNS in an inpatient setting, and 54 were tested in an outpatient setting. Acetylcholine receptor (AChR) binding antibody titer ranged from 0.12 nmol/L to 118 nmol/L. The RNS results were significantly more likely to be positive for seropositive patients, compared with seronegative patients. Patients with MGFA Class III or higher also had higher likelihood of positive RNS results, compared with patients in lower classes. Finally, the diagnostic yield was highest for patients with MGFA Class III or higher who were tested in an inpatient setting.

The study was supported by a Missouri School of Medicine Summer Research Fellowship.

[email protected]

SOURCE: Hua T et al. AANEM 2019, Abstract 9.