CLL

Dual B-cell receptor pathway blockade was tolerable and efficacious for patients with relapsed or refractory chronic lymphocytic leukemia (CLL) or mantle cell lymphoma (MCL) who participated in a multicenter phase 1-1b clinical study that added umbralisib to ibrutinib.

The study “is the first successful combination for two drugs targeting the B-cell receptor pathway,” Matthew S. Davids, MD, of the Dana-Farber Cancer Institute in Boston and his colleagues wrote in the Lancet Haematology.

Of the 21 patients with CLL, 90% (n = 19) achieved an overall response (OR), 62% (n = 13) achieved partial response (PR) or PR with lymphocytosis, and 29% (n = 6) achieved complete response (CR). All patients in complete response still had minimal residual disease (MRD) in bone marrow. No CLL patients had progressive disease.

Of the 21 patients with MCL, 67% (n = 14) had an OR, with 19% (n = 4) showing CR and 48% (n = 10) achieving partial response. Three MCL patients (14%) had progressive disease.

Umbralisib is a next-generation phosphoinositide-3-kinase-delta inhibitor that, when added to the Bruton tyrosine kinase inhibitor (BTKi) ibrutinib, offers once-daily oral dosing. The combination affords the possibility of overcoming the resistance that can come with prolonged ibrutinib monotherapy.

A total of 44 patients were enrolled, and 42 patients (21 with CLL and 21 with MCL) received at least one dose of the study drug and were included in the analysis. At enrollment, patients had received a median of two previous therapies.

Diarrhea was the most frequent adverse event, seen in 22 patients (52%), and half of all patients (n = 21) had infections.

Hematologic toxicities included neutropenia, seen in 9 (43%) of the CLL patients and 8 (38%) of the MCL patients; thrombocytopenia, seen in 6 (29%) of the CLL patients and 10 (48%) of the MCL patients; and anemia, seen in 4 (19%) of the CLL and 9 (43%) of the MCL patients. Grade 3 and 4 hematologic toxicities of any type were less common, occurring in less than 20% of patients. One MCL patient developed febrile neutropenia. According to the study investigators, none of the hematologic toxicities were deemed related to the study drugs.

Adverse events did not appear to be dose-dependent for umbralisib, with the maximum tolerated dose not reached in the study, the investigators wrote. For phase 2 trials, the recommended dose of umbralisib is 800 mg given orally once daily in combination with ibrutinib.

“One unanticipated benefit of doublet B-cell receptor pathway inhibition in this study was the ability to continue one drug when a characteristic toxicity required the other drug to be held,” the investigators wrote.

For MCL patients, 67% achieved OR and 19% achieved CR, figures similar to those reported for ibrutinib monotherapy. However, “the 2-year progression-free survival of 49% and overall survival of 58% suggest that patients who made it to 1 year progression-free had few events during the second year on therapy,” the investigators wrote. They also noted that this MCL population was high risk; more than one-quarter of patients had relapsed after prior autologous stem cell transplantation.

The study was limited by small sample size and a short duration of follow-up, so durability of response can’t yet be assessed. Also, neither pharmacokinetics nor resistance mutations were tracked for participants.

Currently, the doublet regimen is designed to be continuous therapy, and although it’s not known whether this regimen would be effective as time-limited therapy, it’s unlikely because 100% of patients who had CR still had detectable minimal residual disease, the investigators noted.

Umbralisib and ibrutinib are also being explored as part of triplet therapy, with the type 2 CD20 antibody ublituximab, for relapsed or refractory B-cell malignancies (NCT02006485).

“These novel drug-based approaches, along with several others in development, hold promise as highly effective and well-tolerated regimens with the potential to substantially improve outcomes for patients with B-cell malignancies,” the investigators wrote.

The study was supported by TG Therapeutics and the Leukemia and Lymphoma Society Therapy Accelerator Program. The authors reported financial relationships with several pharmaceutical companies, including TG Therapeutics.

[email protected]

SOURCE: Davids MS et al. Lancet Haemtol. 2019;6:e38-47.

Dual B-cell receptor pathway blockade was tolerable and efficacious for patients with relapsed or refractory chronic lymphocytic leukemia (CLL) or mantle cell lymphoma (MCL) who participated in a multicenter phase 1-1b clinical study that added umbralisib to ibrutinib.

The study “is the first successful combination for two drugs targeting the B-cell receptor pathway,” Matthew S. Davids, MD, of the Dana-Farber Cancer Institute in Boston and his colleagues wrote in the Lancet Haematology.

Of the 21 patients with CLL, 90% (n = 19) achieved an overall response (OR), 62% (n = 13) achieved partial response (PR) or PR with lymphocytosis, and 29% (n = 6) achieved complete response (CR). All patients in complete response still had minimal residual disease (MRD) in bone marrow. No CLL patients had progressive disease.

Of the 21 patients with MCL, 67% (n = 14) had an OR, with 19% (n = 4) showing CR and 48% (n = 10) achieving partial response. Three MCL patients (14%) had progressive disease.

Umbralisib is a next-generation phosphoinositide-3-kinase-delta inhibitor that, when added to the Bruton tyrosine kinase inhibitor (BTKi) ibrutinib, offers once-daily oral dosing. The combination affords the possibility of overcoming the resistance that can come with prolonged ibrutinib monotherapy.

A total of 44 patients were enrolled, and 42 patients (21 with CLL and 21 with MCL) received at least one dose of the study drug and were included in the analysis. At enrollment, patients had received a median of two previous therapies.

Diarrhea was the most frequent adverse event, seen in 22 patients (52%), and half of all patients (n = 21) had infections.

Hematologic toxicities included neutropenia, seen in 9 (43%) of the CLL patients and 8 (38%) of the MCL patients; thrombocytopenia, seen in 6 (29%) of the CLL patients and 10 (48%) of the MCL patients; and anemia, seen in 4 (19%) of the CLL and 9 (43%) of the MCL patients. Grade 3 and 4 hematologic toxicities of any type were less common, occurring in less than 20% of patients. One MCL patient developed febrile neutropenia. According to the study investigators, none of the hematologic toxicities were deemed related to the study drugs.

Adverse events did not appear to be dose-dependent for umbralisib, with the maximum tolerated dose not reached in the study, the investigators wrote. For phase 2 trials, the recommended dose of umbralisib is 800 mg given orally once daily in combination with ibrutinib.

“One unanticipated benefit of doublet B-cell receptor pathway inhibition in this study was the ability to continue one drug when a characteristic toxicity required the other drug to be held,” the investigators wrote.

For MCL patients, 67% achieved OR and 19% achieved CR, figures similar to those reported for ibrutinib monotherapy. However, “the 2-year progression-free survival of 49% and overall survival of 58% suggest that patients who made it to 1 year progression-free had few events during the second year on therapy,” the investigators wrote. They also noted that this MCL population was high risk; more than one-quarter of patients had relapsed after prior autologous stem cell transplantation.

The study was limited by small sample size and a short duration of follow-up, so durability of response can’t yet be assessed. Also, neither pharmacokinetics nor resistance mutations were tracked for participants.

Currently, the doublet regimen is designed to be continuous therapy, and although it’s not known whether this regimen would be effective as time-limited therapy, it’s unlikely because 100% of patients who had CR still had detectable minimal residual disease, the investigators noted.

Umbralisib and ibrutinib are also being explored as part of triplet therapy, with the type 2 CD20 antibody ublituximab, for relapsed or refractory B-cell malignancies (NCT02006485).

“These novel drug-based approaches, along with several others in development, hold promise as highly effective and well-tolerated regimens with the potential to substantially improve outcomes for patients with B-cell malignancies,” the investigators wrote.

The study was supported by TG Therapeutics and the Leukemia and Lymphoma Society Therapy Accelerator Program. The authors reported financial relationships with several pharmaceutical companies, including TG Therapeutics.

[email protected]

SOURCE: Davids MS et al. Lancet Haemtol. 2019;6:e38-47.

Dual B-cell receptor pathway blockade was tolerable and efficacious for patients with relapsed or refractory chronic lymphocytic leukemia (CLL) or mantle cell lymphoma (MCL) who participated in a multicenter phase 1-1b clinical study that added umbralisib to ibrutinib.

The study “is the first successful combination for two drugs targeting the B-cell receptor pathway,” Matthew S. Davids, MD, of the Dana-Farber Cancer Institute in Boston and his colleagues wrote in the Lancet Haematology.

Of the 21 patients with CLL, 90% (n = 19) achieved an overall response (OR), 62% (n = 13) achieved partial response (PR) or PR with lymphocytosis, and 29% (n = 6) achieved complete response (CR). All patients in complete response still had minimal residual disease (MRD) in bone marrow. No CLL patients had progressive disease.

Of the 21 patients with MCL, 67% (n = 14) had an OR, with 19% (n = 4) showing CR and 48% (n = 10) achieving partial response. Three MCL patients (14%) had progressive disease.

Umbralisib is a next-generation phosphoinositide-3-kinase-delta inhibitor that, when added to the Bruton tyrosine kinase inhibitor (BTKi) ibrutinib, offers once-daily oral dosing. The combination affords the possibility of overcoming the resistance that can come with prolonged ibrutinib monotherapy.

A total of 44 patients were enrolled, and 42 patients (21 with CLL and 21 with MCL) received at least one dose of the study drug and were included in the analysis. At enrollment, patients had received a median of two previous therapies.

Diarrhea was the most frequent adverse event, seen in 22 patients (52%), and half of all patients (n = 21) had infections.

Hematologic toxicities included neutropenia, seen in 9 (43%) of the CLL patients and 8 (38%) of the MCL patients; thrombocytopenia, seen in 6 (29%) of the CLL patients and 10 (48%) of the MCL patients; and anemia, seen in 4 (19%) of the CLL and 9 (43%) of the MCL patients. Grade 3 and 4 hematologic toxicities of any type were less common, occurring in less than 20% of patients. One MCL patient developed febrile neutropenia. According to the study investigators, none of the hematologic toxicities were deemed related to the study drugs.

Adverse events did not appear to be dose-dependent for umbralisib, with the maximum tolerated dose not reached in the study, the investigators wrote. For phase 2 trials, the recommended dose of umbralisib is 800 mg given orally once daily in combination with ibrutinib.

“One unanticipated benefit of doublet B-cell receptor pathway inhibition in this study was the ability to continue one drug when a characteristic toxicity required the other drug to be held,” the investigators wrote.

For MCL patients, 67% achieved OR and 19% achieved CR, figures similar to those reported for ibrutinib monotherapy. However, “the 2-year progression-free survival of 49% and overall survival of 58% suggest that patients who made it to 1 year progression-free had few events during the second year on therapy,” the investigators wrote. They also noted that this MCL population was high risk; more than one-quarter of patients had relapsed after prior autologous stem cell transplantation.

The study was limited by small sample size and a short duration of follow-up, so durability of response can’t yet be assessed. Also, neither pharmacokinetics nor resistance mutations were tracked for participants.

Currently, the doublet regimen is designed to be continuous therapy, and although it’s not known whether this regimen would be effective as time-limited therapy, it’s unlikely because 100% of patients who had CR still had detectable minimal residual disease, the investigators noted.

Umbralisib and ibrutinib are also being explored as part of triplet therapy, with the type 2 CD20 antibody ublituximab, for relapsed or refractory B-cell malignancies (NCT02006485).

“These novel drug-based approaches, along with several others in development, hold promise as highly effective and well-tolerated regimens with the potential to substantially improve outcomes for patients with B-cell malignancies,” the investigators wrote.

The study was supported by TG Therapeutics and the Leukemia and Lymphoma Society Therapy Accelerator Program. The authors reported financial relationships with several pharmaceutical companies, including TG Therapeutics.

[email protected]

SOURCE: Davids MS et al. Lancet Haemtol. 2019;6:e38-47.

The University of Texas MD Anderson Cancer Center, Houston, and Ascentage Pharma of Suzhou, China, recently formed a 5-year strategic alliance to advance the development of novel cancer therapeutics, primarily for leukemia.

The collaboration, led by Hagop Kantarjian, MD, chair of leukemia at MD Anderson, will use Ascentage’s proprietary Protein-Protein Interaction drug discovery technology platform to develop the company’s apoptosis-targeted and tyrosine kinase inhibitor drug candidates.

The drug candidates will be studied as single-agent therapies and in combinations with other approved or investigational therapeutics. The candidates, chosen for their potential to treat acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphoblastic leukemia (ALL), myeloproliferative neoplasms, and myelofibrosis, include:

• HQP1351, a third-generation BCR-ABL inhibitor that has been shown to be safe and “highly active” in treating patients with chronic- or accelerated-phase CML, with or without the T3151 mutation. Preliminary results of the phase 1 study were presented at the 2018 annual meeting of the American Society of Hematology (Abstract 791).
• APG-1252, a highly potent Bcl-2 family inhibitor, has high binding affinities to Bcl-2, Bcl-xL and Bcl-w. It has achieved tumor regression in small cell lung cancer, colon, breast, and ALL xenografts. A phase 1, dose-escalating study is currently being conducted (NCT03387332).
• APG-2575, a selective Bcl-2 inhibitor, is being studied in a phase 1, multicenter, single-agent trial in patients with B-cell hematologic malignancies, including multiple myeloma, chronic lymphocytic leukemia, lymphoplasmacytic lymphoma, non-Hodgkin lymphomas, and AML (NCT03537482).
• APG-1387, an inhibitor of apoptosis protein, is being studied in solid tumors and hematologic malignancies (NCT03386526). Investigators asserted that combining it with an anti–programmed death 1 antibody would be “a very attractive approach” for cancer therapy. In advanced solid tumors it has been well tolerated with manageable adverse events, according to a study presented at the 2018 annual meeting of the American Society of Clinical Oncology (Abstract 2593).
• APG-115 is an MDM2-p53 inhibitor that, when combined with radiotherapy, has been shown to enhance the antitumor effect in gastric adenocarcinoma, according to a paper published in the Journal of Experimental & Clinical Cancer Research.

“We will be investigating this pipeline of candidate therapies, and we are interested in the novel mechanism of their actions,” Dr. Kantarjian said in a statement.

[email protected]

The University of Texas MD Anderson Cancer Center, Houston, and Ascentage Pharma of Suzhou, China, recently formed a 5-year strategic alliance to advance the development of novel cancer therapeutics, primarily for leukemia.

The collaboration, led by Hagop Kantarjian, MD, chair of leukemia at MD Anderson, will use Ascentage’s proprietary Protein-Protein Interaction drug discovery technology platform to develop the company’s apoptosis-targeted and tyrosine kinase inhibitor drug candidates.

The drug candidates will be studied as single-agent therapies and in combinations with other approved or investigational therapeutics. The candidates, chosen for their potential to treat acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphoblastic leukemia (ALL), myeloproliferative neoplasms, and myelofibrosis, include:

• HQP1351, a third-generation BCR-ABL inhibitor that has been shown to be safe and “highly active” in treating patients with chronic- or accelerated-phase CML, with or without the T3151 mutation. Preliminary results of the phase 1 study were presented at the 2018 annual meeting of the American Society of Hematology (Abstract 791).
• APG-1252, a highly potent Bcl-2 family inhibitor, has high binding affinities to Bcl-2, Bcl-xL and Bcl-w. It has achieved tumor regression in small cell lung cancer, colon, breast, and ALL xenografts. A phase 1, dose-escalating study is currently being conducted (NCT03387332).
• APG-2575, a selective Bcl-2 inhibitor, is being studied in a phase 1, multicenter, single-agent trial in patients with B-cell hematologic malignancies, including multiple myeloma, chronic lymphocytic leukemia, lymphoplasmacytic lymphoma, non-Hodgkin lymphomas, and AML (NCT03537482).
• APG-1387, an inhibitor of apoptosis protein, is being studied in solid tumors and hematologic malignancies (NCT03386526). Investigators asserted that combining it with an anti–programmed death 1 antibody would be “a very attractive approach” for cancer therapy. In advanced solid tumors it has been well tolerated with manageable adverse events, according to a study presented at the 2018 annual meeting of the American Society of Clinical Oncology (Abstract 2593).
• APG-115 is an MDM2-p53 inhibitor that, when combined with radiotherapy, has been shown to enhance the antitumor effect in gastric adenocarcinoma, according to a paper published in the Journal of Experimental & Clinical Cancer Research.

“We will be investigating this pipeline of candidate therapies, and we are interested in the novel mechanism of their actions,” Dr. Kantarjian said in a statement.

[email protected]

The University of Texas MD Anderson Cancer Center, Houston, and Ascentage Pharma of Suzhou, China, recently formed a 5-year strategic alliance to advance the development of novel cancer therapeutics, primarily for leukemia.

The collaboration, led by Hagop Kantarjian, MD, chair of leukemia at MD Anderson, will use Ascentage’s proprietary Protein-Protein Interaction drug discovery technology platform to develop the company’s apoptosis-targeted and tyrosine kinase inhibitor drug candidates.

The drug candidates will be studied as single-agent therapies and in combinations with other approved or investigational therapeutics. The candidates, chosen for their potential to treat acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphoblastic leukemia (ALL), myeloproliferative neoplasms, and myelofibrosis, include:

• HQP1351, a third-generation BCR-ABL inhibitor that has been shown to be safe and “highly active” in treating patients with chronic- or accelerated-phase CML, with or without the T3151 mutation. Preliminary results of the phase 1 study were presented at the 2018 annual meeting of the American Society of Hematology (Abstract 791).
• APG-1252, a highly potent Bcl-2 family inhibitor, has high binding affinities to Bcl-2, Bcl-xL and Bcl-w. It has achieved tumor regression in small cell lung cancer, colon, breast, and ALL xenografts. A phase 1, dose-escalating study is currently being conducted (NCT03387332).
• APG-2575, a selective Bcl-2 inhibitor, is being studied in a phase 1, multicenter, single-agent trial in patients with B-cell hematologic malignancies, including multiple myeloma, chronic lymphocytic leukemia, lymphoplasmacytic lymphoma, non-Hodgkin lymphomas, and AML (NCT03537482).
• APG-1387, an inhibitor of apoptosis protein, is being studied in solid tumors and hematologic malignancies (NCT03386526). Investigators asserted that combining it with an anti–programmed death 1 antibody would be “a very attractive approach” for cancer therapy. In advanced solid tumors it has been well tolerated with manageable adverse events, according to a study presented at the 2018 annual meeting of the American Society of Clinical Oncology (Abstract 2593).
• APG-115 is an MDM2-p53 inhibitor that, when combined with radiotherapy, has been shown to enhance the antitumor effect in gastric adenocarcinoma, according to a paper published in the Journal of Experimental & Clinical Cancer Research.

“We will be investigating this pipeline of candidate therapies, and we are interested in the novel mechanism of their actions,” Dr. Kantarjian said in a statement.

[email protected]

SAN DIEGO – A second-generation CD19-specific “armored” chimeric antigen receptor (CAR) T-cell construct was associated with high complete remission rates in diffuse large B-cell lymphoma (DLBCL) and indolent non-Hodgkin lymphoma (NHL) in a phase 1 trial.

Neil Osterweil/ MDedge News

The CAR T construct – labeled 1928z-41BBL – also induced “encouraging” complete remission rates in patients with chronic lymphocytic leukemia (CLL) with Richter’s transformation, reported Jae H. Park, MD, of Memorial Sloan Kettering Cancer Center (MSKCC), New York, and his colleagues.

“Interestingly and encouragingly, severe [cytokine release syndrome] was not seen and grade 3 neurotoxicity was observed in less than 10%, with no grade 4 neurotoxicity, so there appears to be a favorable side effect profile,” Dr. Park said at the annual meeting of the American Society of Hematology.

Just as armored cars are designed to protect their valuable contents from people with bad intent, armored CAR T cells are engineered to protect the modified T-cells from a hostile tumor microenvironment and simultaneously recruit non-modified T cells to the target to produce a more robust immune response against malignant cells.

MSKCC investigators had previously shown that in contrast to other CAR T-cell constructs, the 1928z-41BBL configuration, which consists of two signaling domains (CD28 and CD3zeta) and the 4-1BB ligand, hit the sweet spot between tumor-killing function and T-cell persistence (Cancer Cell. 2015 Oct 12;28[4]:415-28).

In the current study, they enrolled 35 adults with relapsed or refractory CD19-positive hematologic malignancies, 29 of whom eventually underwent CAR T-cell infusions. The treated population comprised 14 patients with CLL (4 of whom had Richter’s transformation), 9 with DLBCL, 5 with indolent NHL, and 1 with acute lymphoblastic leukemia.

The patients with CLL had received a median of 5.5 prior lines of therapy, including ibrutinib (Imbruvica) and venetoclax (Venclexta).

There were 15 complete remissions (CR), with CR rates of 78% in DLBCL, 20% in CLL, 67% in CLL with Richter’s transformation, 60% in patients with indolent NHL, as well as CR in the single patient with ALL.

There were eight partial remissions. One patient with CLL had stable disease, and four patients had disease progression (one patient each with DLBCL, CLL, CLL with Richter’s, and indolent NHL).

Dr. Park noted that T cells are being detected in peripheral blood more than 6 months after T-cell infusion.

There were no cases of severe cytokine release syndrome, defined as requiring vasopressors and/or mechanical ventilation for hypoxia, and just three cases of grade 3 neurotoxicity. There were no cases of grade 4 neurotoxicity, no deaths related to neurotoxicity, and no cases of cerebral edema – a serious complication that has been seen in earlier CAR T-cell studies.

Split or multiple infusions of CAR T cells or incorporation of the technique into earlier lines of therapy might generate higher response rates, Dr. Park said.

The study was supported by Juno Therapeutics. Dr. Park reported consulting for and research funding from Juno, and financial relationships with other companies.
 

SOURCE: Park JH et al. ASH 2018, Abstract 224.

SAN DIEGO – A second-generation CD19-specific “armored” chimeric antigen receptor (CAR) T-cell construct was associated with high complete remission rates in diffuse large B-cell lymphoma (DLBCL) and indolent non-Hodgkin lymphoma (NHL) in a phase 1 trial.

Neil Osterweil/ MDedge News

The CAR T construct – labeled 1928z-41BBL – also induced “encouraging” complete remission rates in patients with chronic lymphocytic leukemia (CLL) with Richter’s transformation, reported Jae H. Park, MD, of Memorial Sloan Kettering Cancer Center (MSKCC), New York, and his colleagues.

“Interestingly and encouragingly, severe [cytokine release syndrome] was not seen and grade 3 neurotoxicity was observed in less than 10%, with no grade 4 neurotoxicity, so there appears to be a favorable side effect profile,” Dr. Park said at the annual meeting of the American Society of Hematology.

Just as armored cars are designed to protect their valuable contents from people with bad intent, armored CAR T cells are engineered to protect the modified T-cells from a hostile tumor microenvironment and simultaneously recruit non-modified T cells to the target to produce a more robust immune response against malignant cells.

MSKCC investigators had previously shown that in contrast to other CAR T-cell constructs, the 1928z-41BBL configuration, which consists of two signaling domains (CD28 and CD3zeta) and the 4-1BB ligand, hit the sweet spot between tumor-killing function and T-cell persistence (Cancer Cell. 2015 Oct 12;28[4]:415-28).

In the current study, they enrolled 35 adults with relapsed or refractory CD19-positive hematologic malignancies, 29 of whom eventually underwent CAR T-cell infusions. The treated population comprised 14 patients with CLL (4 of whom had Richter’s transformation), 9 with DLBCL, 5 with indolent NHL, and 1 with acute lymphoblastic leukemia.

The patients with CLL had received a median of 5.5 prior lines of therapy, including ibrutinib (Imbruvica) and venetoclax (Venclexta).

There were 15 complete remissions (CR), with CR rates of 78% in DLBCL, 20% in CLL, 67% in CLL with Richter’s transformation, 60% in patients with indolent NHL, as well as CR in the single patient with ALL.

There were eight partial remissions. One patient with CLL had stable disease, and four patients had disease progression (one patient each with DLBCL, CLL, CLL with Richter’s, and indolent NHL).

Dr. Park noted that T cells are being detected in peripheral blood more than 6 months after T-cell infusion.

There were no cases of severe cytokine release syndrome, defined as requiring vasopressors and/or mechanical ventilation for hypoxia, and just three cases of grade 3 neurotoxicity. There were no cases of grade 4 neurotoxicity, no deaths related to neurotoxicity, and no cases of cerebral edema – a serious complication that has been seen in earlier CAR T-cell studies.

Split or multiple infusions of CAR T cells or incorporation of the technique into earlier lines of therapy might generate higher response rates, Dr. Park said.

The study was supported by Juno Therapeutics. Dr. Park reported consulting for and research funding from Juno, and financial relationships with other companies.
 

SOURCE: Park JH et al. ASH 2018, Abstract 224.

SAN DIEGO – A second-generation CD19-specific “armored” chimeric antigen receptor (CAR) T-cell construct was associated with high complete remission rates in diffuse large B-cell lymphoma (DLBCL) and indolent non-Hodgkin lymphoma (NHL) in a phase 1 trial.

Neil Osterweil/ MDedge News

The CAR T construct – labeled 1928z-41BBL – also induced “encouraging” complete remission rates in patients with chronic lymphocytic leukemia (CLL) with Richter’s transformation, reported Jae H. Park, MD, of Memorial Sloan Kettering Cancer Center (MSKCC), New York, and his colleagues.

“Interestingly and encouragingly, severe [cytokine release syndrome] was not seen and grade 3 neurotoxicity was observed in less than 10%, with no grade 4 neurotoxicity, so there appears to be a favorable side effect profile,” Dr. Park said at the annual meeting of the American Society of Hematology.

Just as armored cars are designed to protect their valuable contents from people with bad intent, armored CAR T cells are engineered to protect the modified T-cells from a hostile tumor microenvironment and simultaneously recruit non-modified T cells to the target to produce a more robust immune response against malignant cells.

MSKCC investigators had previously shown that in contrast to other CAR T-cell constructs, the 1928z-41BBL configuration, which consists of two signaling domains (CD28 and CD3zeta) and the 4-1BB ligand, hit the sweet spot between tumor-killing function and T-cell persistence (Cancer Cell. 2015 Oct 12;28[4]:415-28).

In the current study, they enrolled 35 adults with relapsed or refractory CD19-positive hematologic malignancies, 29 of whom eventually underwent CAR T-cell infusions. The treated population comprised 14 patients with CLL (4 of whom had Richter’s transformation), 9 with DLBCL, 5 with indolent NHL, and 1 with acute lymphoblastic leukemia.

The patients with CLL had received a median of 5.5 prior lines of therapy, including ibrutinib (Imbruvica) and venetoclax (Venclexta).

There were 15 complete remissions (CR), with CR rates of 78% in DLBCL, 20% in CLL, 67% in CLL with Richter’s transformation, 60% in patients with indolent NHL, as well as CR in the single patient with ALL.

There were eight partial remissions. One patient with CLL had stable disease, and four patients had disease progression (one patient each with DLBCL, CLL, CLL with Richter’s, and indolent NHL).

Dr. Park noted that T cells are being detected in peripheral blood more than 6 months after T-cell infusion.

There were no cases of severe cytokine release syndrome, defined as requiring vasopressors and/or mechanical ventilation for hypoxia, and just three cases of grade 3 neurotoxicity. There were no cases of grade 4 neurotoxicity, no deaths related to neurotoxicity, and no cases of cerebral edema – a serious complication that has been seen in earlier CAR T-cell studies.

Split or multiple infusions of CAR T cells or incorporation of the technique into earlier lines of therapy might generate higher response rates, Dr. Park said.

The study was supported by Juno Therapeutics. Dr. Park reported consulting for and research funding from Juno, and financial relationships with other companies.
 

SOURCE: Park JH et al. ASH 2018, Abstract 224.

SAN DIEGO – Longer-term follow-up of patients treated with CD19-targeted chimeric antigen receptor (CAR) T cells for hematologic malignancies indicates that the altered cells are generally safe, with most late events being mild in nature and possibly related to therapies delivered before or after CAR T cells, investigators reported.

Among patients treated with CD19-targeted CAR T cells for relapsed or refractory chronic lymphocytic leukemia (CLL) or non-Hodgkin lymphoma (NHL), the most frequent late adverse event was hypogammaglobulinemia, which occurred in 29 of 48 patients evaluated, reported Ana Cordeiro, MD, from the Fred Hutchinson Cancer Research Center in Seattle.

“Our results suggest that CD19 CAR T cells are safe,” Dr. Cordeiro said at the annual meeting of the American Society of Hematology. “However, continuing with prospective systematic and long-term follow-up of these patients is required for better understanding of these late effects.”

Dr. Cordeiro and colleagues studied a total of 60 patients who were enrolled in a phase 1/2 trial at their center of a CD19-targeted CAR T-cell construct and survived for at least 1 year.

The goal of the study was to describe complications that occurred or persisted beyond 90 days after CAR T-cell infusion.

The cohort included 43 patients treated for NHL and 17 treated for CLL. Patients with CLL were followed for a median of 27.5 months, and patients with NHL were followed for a median of 23.8 months.

As of September 2018, 47 patients were still alive, including 15 patients with CLL (88%) and 32 patients with NHL (74%). Of the 17 patients who died, 10 died from progressive disease (2 from CLL and 8 from NHL), and 3 patients died from nonrelapse causes associated with complications from subsequent allogeneic stem cell transplantation (allo-HCT), including 1 patient from graft-versus-host disease (GVHD) and infection, 1 from infection, and 1 from cerberovascular accident/thrombotic microangiopathy.

Of 38 patients who received additional therapies, 17 had subsequent CAR T-cell infusions under the same protocol, and 16 went on to allo-HCT. Treatments for the remaining five patients were not specified.

Of the 22 patients who did not receive additional treatment for their primary malignancies, 21 were in ongoing complete remission following a single CAR T-cell infusion after a median follow-up of 28 months. However, two patients in this group did require treatment for therapy-related myelodysplastic syndrome (t-MDS). The remaining patient had a small CLL clone at last follow-up.

Late adverse events included the following:

• Late significant cytopenias in three of 19 patients evaluated.
• Late hypogammaglobulinemia in 29 of 48 evaluated patients.
• A total of 138 late infections in 31 of the 60 patients.
• Subsequent malignancies in 10 of the 60 patients, including t-MDS, nonmelanoma skin cancer, and noninvasive bladder cancer.
• Late immune-related events in seven patients.
• Late neurogenic/psychiatric events, including one case each of transient ischemic attack at 3.8 months, encephalopathy and myoclonic seizure in the setting of chemotherapy, and a fatal cerebrovascular accident in the setting of allo-HCT and thrombotic microangiopathy. These patients did not have acute neurotoxicity after CAR T-cell therapy, Dr. Cordeiro noted. In addition, three patients experienced exacerbation of depression or anxiety following infusion.
• GVHD in nine patients at a median time from allo-HCT to first CAR T-cell infusion of 46.3 months (range, 6.7 months to 11 years).

Focusing on those patients who achieve complete remissions after CAR T-cell therapy could help investigators isolate late events that are most likely related to CAR T cells, Dr. Cordeiro said.

Dr. Cordeiro reported having no relevant conflicts of interest.

SOURCE: Cordeiro A et al. ASH 2018, Abstract 223.

SAN DIEGO – Longer-term follow-up of patients treated with CD19-targeted chimeric antigen receptor (CAR) T cells for hematologic malignancies indicates that the altered cells are generally safe, with most late events being mild in nature and possibly related to therapies delivered before or after CAR T cells, investigators reported.

Among patients treated with CD19-targeted CAR T cells for relapsed or refractory chronic lymphocytic leukemia (CLL) or non-Hodgkin lymphoma (NHL), the most frequent late adverse event was hypogammaglobulinemia, which occurred in 29 of 48 patients evaluated, reported Ana Cordeiro, MD, from the Fred Hutchinson Cancer Research Center in Seattle.

“Our results suggest that CD19 CAR T cells are safe,” Dr. Cordeiro said at the annual meeting of the American Society of Hematology. “However, continuing with prospective systematic and long-term follow-up of these patients is required for better understanding of these late effects.”

Dr. Cordeiro and colleagues studied a total of 60 patients who were enrolled in a phase 1/2 trial at their center of a CD19-targeted CAR T-cell construct and survived for at least 1 year.

The goal of the study was to describe complications that occurred or persisted beyond 90 days after CAR T-cell infusion.

The cohort included 43 patients treated for NHL and 17 treated for CLL. Patients with CLL were followed for a median of 27.5 months, and patients with NHL were followed for a median of 23.8 months.

As of September 2018, 47 patients were still alive, including 15 patients with CLL (88%) and 32 patients with NHL (74%). Of the 17 patients who died, 10 died from progressive disease (2 from CLL and 8 from NHL), and 3 patients died from nonrelapse causes associated with complications from subsequent allogeneic stem cell transplantation (allo-HCT), including 1 patient from graft-versus-host disease (GVHD) and infection, 1 from infection, and 1 from cerberovascular accident/thrombotic microangiopathy.

Of 38 patients who received additional therapies, 17 had subsequent CAR T-cell infusions under the same protocol, and 16 went on to allo-HCT. Treatments for the remaining five patients were not specified.

Of the 22 patients who did not receive additional treatment for their primary malignancies, 21 were in ongoing complete remission following a single CAR T-cell infusion after a median follow-up of 28 months. However, two patients in this group did require treatment for therapy-related myelodysplastic syndrome (t-MDS). The remaining patient had a small CLL clone at last follow-up.

Late adverse events included the following:

• Late significant cytopenias in three of 19 patients evaluated.
• Late hypogammaglobulinemia in 29 of 48 evaluated patients.
• A total of 138 late infections in 31 of the 60 patients.
• Subsequent malignancies in 10 of the 60 patients, including t-MDS, nonmelanoma skin cancer, and noninvasive bladder cancer.
• Late immune-related events in seven patients.
• Late neurogenic/psychiatric events, including one case each of transient ischemic attack at 3.8 months, encephalopathy and myoclonic seizure in the setting of chemotherapy, and a fatal cerebrovascular accident in the setting of allo-HCT and thrombotic microangiopathy. These patients did not have acute neurotoxicity after CAR T-cell therapy, Dr. Cordeiro noted. In addition, three patients experienced exacerbation of depression or anxiety following infusion.
• GVHD in nine patients at a median time from allo-HCT to first CAR T-cell infusion of 46.3 months (range, 6.7 months to 11 years).

Focusing on those patients who achieve complete remissions after CAR T-cell therapy could help investigators isolate late events that are most likely related to CAR T cells, Dr. Cordeiro said.

Dr. Cordeiro reported having no relevant conflicts of interest.

SOURCE: Cordeiro A et al. ASH 2018, Abstract 223.

SAN DIEGO – Longer-term follow-up of patients treated with CD19-targeted chimeric antigen receptor (CAR) T cells for hematologic malignancies indicates that the altered cells are generally safe, with most late events being mild in nature and possibly related to therapies delivered before or after CAR T cells, investigators reported.

Among patients treated with CD19-targeted CAR T cells for relapsed or refractory chronic lymphocytic leukemia (CLL) or non-Hodgkin lymphoma (NHL), the most frequent late adverse event was hypogammaglobulinemia, which occurred in 29 of 48 patients evaluated, reported Ana Cordeiro, MD, from the Fred Hutchinson Cancer Research Center in Seattle.

“Our results suggest that CD19 CAR T cells are safe,” Dr. Cordeiro said at the annual meeting of the American Society of Hematology. “However, continuing with prospective systematic and long-term follow-up of these patients is required for better understanding of these late effects.”

Dr. Cordeiro and colleagues studied a total of 60 patients who were enrolled in a phase 1/2 trial at their center of a CD19-targeted CAR T-cell construct and survived for at least 1 year.

The goal of the study was to describe complications that occurred or persisted beyond 90 days after CAR T-cell infusion.

The cohort included 43 patients treated for NHL and 17 treated for CLL. Patients with CLL were followed for a median of 27.5 months, and patients with NHL were followed for a median of 23.8 months.

As of September 2018, 47 patients were still alive, including 15 patients with CLL (88%) and 32 patients with NHL (74%). Of the 17 patients who died, 10 died from progressive disease (2 from CLL and 8 from NHL), and 3 patients died from nonrelapse causes associated with complications from subsequent allogeneic stem cell transplantation (allo-HCT), including 1 patient from graft-versus-host disease (GVHD) and infection, 1 from infection, and 1 from cerberovascular accident/thrombotic microangiopathy.

Of 38 patients who received additional therapies, 17 had subsequent CAR T-cell infusions under the same protocol, and 16 went on to allo-HCT. Treatments for the remaining five patients were not specified.

Of the 22 patients who did not receive additional treatment for their primary malignancies, 21 were in ongoing complete remission following a single CAR T-cell infusion after a median follow-up of 28 months. However, two patients in this group did require treatment for therapy-related myelodysplastic syndrome (t-MDS). The remaining patient had a small CLL clone at last follow-up.

Late adverse events included the following:

• Late significant cytopenias in three of 19 patients evaluated.
• Late hypogammaglobulinemia in 29 of 48 evaluated patients.
• A total of 138 late infections in 31 of the 60 patients.
• Subsequent malignancies in 10 of the 60 patients, including t-MDS, nonmelanoma skin cancer, and noninvasive bladder cancer.
• Late immune-related events in seven patients.
• Late neurogenic/psychiatric events, including one case each of transient ischemic attack at 3.8 months, encephalopathy and myoclonic seizure in the setting of chemotherapy, and a fatal cerebrovascular accident in the setting of allo-HCT and thrombotic microangiopathy. These patients did not have acute neurotoxicity after CAR T-cell therapy, Dr. Cordeiro noted. In addition, three patients experienced exacerbation of depression or anxiety following infusion.
• GVHD in nine patients at a median time from allo-HCT to first CAR T-cell infusion of 46.3 months (range, 6.7 months to 11 years).

Focusing on those patients who achieve complete remissions after CAR T-cell therapy could help investigators isolate late events that are most likely related to CAR T cells, Dr. Cordeiro said.

Dr. Cordeiro reported having no relevant conflicts of interest.

SOURCE: Cordeiro A et al. ASH 2018, Abstract 223.

SAN DIEGO – There was a mountain of data presented at the annual meeting of the American Society of Hematology on the use of novel agents – both as frontline therapy and in combination – for the treatment of chronic lymphocytic leukemia (CLL).

In a video interview at the meeting, Brian T. Hill, MD, PhD, of the Cleveland Clinic and Anthony Mato, MD, of Memorial Sloan Kettering Cancer Center, New York, summed up the key studies and what they mean in practice. They also looked ahead at what data are still missing that could aid in making important treatment decisions.

Dr. Hill highlighted the late-breaking abstract on the ECOG-ACRIN Cancer Research Group E1912 trial comparing ibrutinib-rituximab to a chemotherapy regimen of fludarabine, cyclophosphamide, and rituximab (FCR) in previously untreated patients under age 70 years (Abstract LBA-4). Not only was there a progression-free survival benefit with the use of the ibrutinib regimen, but there was an overall survival benefit as well, he noted.

Dr. Mato pointed to notable results from the Alliance A041202 trial of older patients with previously untreated disease that compared ibrutinib alone or in combination with rituximab, with bendamustine plus rituximab (Abstract #6). The ibrutinib-containing regimens resulted in superior progression-free survival.

The two trials taken together show a movement away from chemotherapy in the frontline setting and toward targeted agents for CLL, Dr. Mato said. “What that agent or combination of agents will be, remains to be seen,” he said. “We have now a real message about the fact that we’re ending, potentially, the era of chemotherapy for patients with CLL, which is a very welcome change.”

Dr. Mato and Dr. Hill will be discussing these trials and more CLL data during a Twitter chat on Jan. 31, 2019, from 7 p.m. to 8 p.m. EST. Join in the conversation by using and following #MDedgeChats.

[email protected]

SAN DIEGO – There was a mountain of data presented at the annual meeting of the American Society of Hematology on the use of novel agents – both as frontline therapy and in combination – for the treatment of chronic lymphocytic leukemia (CLL).

In a video interview at the meeting, Brian T. Hill, MD, PhD, of the Cleveland Clinic and Anthony Mato, MD, of Memorial Sloan Kettering Cancer Center, New York, summed up the key studies and what they mean in practice. They also looked ahead at what data are still missing that could aid in making important treatment decisions.

Dr. Hill highlighted the late-breaking abstract on the ECOG-ACRIN Cancer Research Group E1912 trial comparing ibrutinib-rituximab to a chemotherapy regimen of fludarabine, cyclophosphamide, and rituximab (FCR) in previously untreated patients under age 70 years (Abstract LBA-4). Not only was there a progression-free survival benefit with the use of the ibrutinib regimen, but there was an overall survival benefit as well, he noted.

Dr. Mato pointed to notable results from the Alliance A041202 trial of older patients with previously untreated disease that compared ibrutinib alone or in combination with rituximab, with bendamustine plus rituximab (Abstract #6). The ibrutinib-containing regimens resulted in superior progression-free survival.

The two trials taken together show a movement away from chemotherapy in the frontline setting and toward targeted agents for CLL, Dr. Mato said. “What that agent or combination of agents will be, remains to be seen,” he said. “We have now a real message about the fact that we’re ending, potentially, the era of chemotherapy for patients with CLL, which is a very welcome change.”

Dr. Mato and Dr. Hill will be discussing these trials and more CLL data during a Twitter chat on Jan. 31, 2019, from 7 p.m. to 8 p.m. EST. Join in the conversation by using and following #MDedgeChats.

[email protected]

SAN DIEGO – There was a mountain of data presented at the annual meeting of the American Society of Hematology on the use of novel agents – both as frontline therapy and in combination – for the treatment of chronic lymphocytic leukemia (CLL).

In a video interview at the meeting, Brian T. Hill, MD, PhD, of the Cleveland Clinic and Anthony Mato, MD, of Memorial Sloan Kettering Cancer Center, New York, summed up the key studies and what they mean in practice. They also looked ahead at what data are still missing that could aid in making important treatment decisions.

Dr. Hill highlighted the late-breaking abstract on the ECOG-ACRIN Cancer Research Group E1912 trial comparing ibrutinib-rituximab to a chemotherapy regimen of fludarabine, cyclophosphamide, and rituximab (FCR) in previously untreated patients under age 70 years (Abstract LBA-4). Not only was there a progression-free survival benefit with the use of the ibrutinib regimen, but there was an overall survival benefit as well, he noted.

Dr. Mato pointed to notable results from the Alliance A041202 trial of older patients with previously untreated disease that compared ibrutinib alone or in combination with rituximab, with bendamustine plus rituximab (Abstract #6). The ibrutinib-containing regimens resulted in superior progression-free survival.

The two trials taken together show a movement away from chemotherapy in the frontline setting and toward targeted agents for CLL, Dr. Mato said. “What that agent or combination of agents will be, remains to be seen,” he said. “We have now a real message about the fact that we’re ending, potentially, the era of chemotherapy for patients with CLL, which is a very welcome change.”

Dr. Mato and Dr. Hill will be discussing these trials and more CLL data during a Twitter chat on Jan. 31, 2019, from 7 p.m. to 8 p.m. EST. Join in the conversation by using and following #MDedgeChats.

[email protected]

SAN DIEGO – The combination of ibrutinib and rituximab was associated with a two-thirds reduction in chronic lymphocytic leukemia (CLL) progression, compared with standard chemoimmunotherapy in patients younger than 70 years old, interim results of a phase 3 randomized trial showed.

Among 529 patients with previously untreated, symptomatic CLL randomly assigned to ibrutinib-rituximab (IR) or to chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab (FCR), the IR regimen was associated with a 65% reduction in risk for disease progression, which was the trial’s primary endpoint.

The IR regimen was also associated with better overall survival out to 4 years of follow-up, reported Tait D. Shanafelt, MD, of Stanford (Calif.) University.

“This establishes ibrutinib-based therapy as the most effective treatment tested to date in this disease for untreated patients,” he said at a media briefing prior at the annual meeting of the American Society of Hematology.

The study results are likely to dethrone FCR as the most active chemoimmunotherapy regimen against CLL, Dr. Shanafelt said.

In the ECOG-ACRIN Cancer Research Group E1912 trial, 529 patients aged 70 or younger with previously untreated CLL were enrolled and randomly assigned on a 2:1 basis to either standard therapy with six cycles of FCR according to standard protocols (175 patients), or IR, with ibrutinib 420 mg daily for each cycle, and rituximab delivered 50 mg/m² intravenously on day 1 of cycle 2, and 325 mg/m² on day 2 of the same cycle, and 500 mg/m² on day 1 for all remaining cycles (354 patients).

From cycle 8 until progression, patients in the IR arm received daily ibrutinib 420 mg.

Dr. Shanafelt presented results from both an intention-to-treat analysis and a per-protocol analysis excluding 22 patients in the IR arm and 9 patients in the FCR arm who were randomized but later found not to meet eligibility criteria.

After a mean follow-up of 34 months, there were 37 PFS events in the IR arm, compared with 40 events in the FCR arm in an intention-to-treat analysis. The difference translated into a hazard ratio for progression of 0.35 with IR (P less than .00001).

The results were similar in the per-protocol analysis, with an HR of 0.32 favoring IR (P less than .00001).*

There were four deaths in the IR arm, compared with 10 in the FCR arm at the time of the data lock, translating into a hazard ratio (HR) for overall survival of 0.17 (P less than .0003) in the intention-to-treat analysis, and 0.13 in the per-protocol analysis (P less than .0001).

Dr. Shanafelt noted that although the overall number of deaths was relatively small, there were twice as many patients enrolled in the IR arm as in the FCR arm, meaning that the rate of deaths in the FCR arm was fivefold higher than in the IR arm.

In a subgroup analysis of PFS, IR was superior to FCR regardless of patient age, sex, performance status, disease stage, or the presence or absence of the 11q23.3 deletion.

PFS was also significantly better with IR in patients with unmutated immunoglobulin heavy chain variable (IGHV) regions (HR 0.26, P less than .00001), but not in patients with mutated IGHV.*

Grade 3 or greater treatment-related adverse events occurred in 58.5% of patients in the IR arm, compared with 72.1% of patients in the FCR arm. Specific events that occurred significantly less often with IR included neutropenia (22.7% vs. 43.7%), anemia (2.6% vs. 12.0%), thrombocytopenia (2.9% vs. 13.9%), any infection (7.1% vs. 19.0%), and neutropenic fever (2.3% vs. 15.8%; P less than .001 for all comparisons).

Events that occurred more frequently with IR than FCR included atrial fibrillation (2.9% vs. 0%, P = .04), and hypertension (7.4% vs. 1.9%, P = .01).

Dr. Shanafelt acknowledged that one possible barrier to the IR regimen is cost; the monthly cost of ibrutinib maintenance is about $10,000, he said, although he noted that cost considerations were not studied in the trial.

“Future trials testing novel agent combinations to see if we can eliminate the need for chronic therapy should be pursued,” he said.

The trial was sponsored by the National Cancer Institute with additional support from Pharmacyclics. Dr. Shanafelt reported patents and royalties from the Mayo Clinic, and research funding from Celgene, GlaxoSmithKline, Genentech, Abbvie, Pharmacyclics, and Janssen.

SOURCE: Shanafelt TD et al. ASH 2018, Abstract LBA-4.

*Correction, 12/12/2018: An earlier version of this story misstated the P value in two comparisons.

SAN DIEGO – The combination of ibrutinib and rituximab was associated with a two-thirds reduction in chronic lymphocytic leukemia (CLL) progression, compared with standard chemoimmunotherapy in patients younger than 70 years old, interim results of a phase 3 randomized trial showed.

Among 529 patients with previously untreated, symptomatic CLL randomly assigned to ibrutinib-rituximab (IR) or to chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab (FCR), the IR regimen was associated with a 65% reduction in risk for disease progression, which was the trial’s primary endpoint.

The IR regimen was also associated with better overall survival out to 4 years of follow-up, reported Tait D. Shanafelt, MD, of Stanford (Calif.) University.

“This establishes ibrutinib-based therapy as the most effective treatment tested to date in this disease for untreated patients,” he said at a media briefing prior at the annual meeting of the American Society of Hematology.

The study results are likely to dethrone FCR as the most active chemoimmunotherapy regimen against CLL, Dr. Shanafelt said.

In the ECOG-ACRIN Cancer Research Group E1912 trial, 529 patients aged 70 or younger with previously untreated CLL were enrolled and randomly assigned on a 2:1 basis to either standard therapy with six cycles of FCR according to standard protocols (175 patients), or IR, with ibrutinib 420 mg daily for each cycle, and rituximab delivered 50 mg/m² intravenously on day 1 of cycle 2, and 325 mg/m² on day 2 of the same cycle, and 500 mg/m² on day 1 for all remaining cycles (354 patients).

From cycle 8 until progression, patients in the IR arm received daily ibrutinib 420 mg.

Dr. Shanafelt presented results from both an intention-to-treat analysis and a per-protocol analysis excluding 22 patients in the IR arm and 9 patients in the FCR arm who were randomized but later found not to meet eligibility criteria.

After a mean follow-up of 34 months, there were 37 PFS events in the IR arm, compared with 40 events in the FCR arm in an intention-to-treat analysis. The difference translated into a hazard ratio for progression of 0.35 with IR (P less than .00001).

The results were similar in the per-protocol analysis, with an HR of 0.32 favoring IR (P less than .00001).*

There were four deaths in the IR arm, compared with 10 in the FCR arm at the time of the data lock, translating into a hazard ratio (HR) for overall survival of 0.17 (P less than .0003) in the intention-to-treat analysis, and 0.13 in the per-protocol analysis (P less than .0001).

Dr. Shanafelt noted that although the overall number of deaths was relatively small, there were twice as many patients enrolled in the IR arm as in the FCR arm, meaning that the rate of deaths in the FCR arm was fivefold higher than in the IR arm.

In a subgroup analysis of PFS, IR was superior to FCR regardless of patient age, sex, performance status, disease stage, or the presence or absence of the 11q23.3 deletion.

PFS was also significantly better with IR in patients with unmutated immunoglobulin heavy chain variable (IGHV) regions (HR 0.26, P less than .00001), but not in patients with mutated IGHV.*

Grade 3 or greater treatment-related adverse events occurred in 58.5% of patients in the IR arm, compared with 72.1% of patients in the FCR arm. Specific events that occurred significantly less often with IR included neutropenia (22.7% vs. 43.7%), anemia (2.6% vs. 12.0%), thrombocytopenia (2.9% vs. 13.9%), any infection (7.1% vs. 19.0%), and neutropenic fever (2.3% vs. 15.8%; P less than .001 for all comparisons).

Events that occurred more frequently with IR than FCR included atrial fibrillation (2.9% vs. 0%, P = .04), and hypertension (7.4% vs. 1.9%, P = .01).

Dr. Shanafelt acknowledged that one possible barrier to the IR regimen is cost; the monthly cost of ibrutinib maintenance is about $10,000, he said, although he noted that cost considerations were not studied in the trial.

“Future trials testing novel agent combinations to see if we can eliminate the need for chronic therapy should be pursued,” he said.

The trial was sponsored by the National Cancer Institute with additional support from Pharmacyclics. Dr. Shanafelt reported patents and royalties from the Mayo Clinic, and research funding from Celgene, GlaxoSmithKline, Genentech, Abbvie, Pharmacyclics, and Janssen.

SOURCE: Shanafelt TD et al. ASH 2018, Abstract LBA-4.

*Correction, 12/12/2018: An earlier version of this story misstated the P value in two comparisons.

SAN DIEGO – The combination of ibrutinib and rituximab was associated with a two-thirds reduction in chronic lymphocytic leukemia (CLL) progression, compared with standard chemoimmunotherapy in patients younger than 70 years old, interim results of a phase 3 randomized trial showed.

Among 529 patients with previously untreated, symptomatic CLL randomly assigned to ibrutinib-rituximab (IR) or to chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab (FCR), the IR regimen was associated with a 65% reduction in risk for disease progression, which was the trial’s primary endpoint.

The IR regimen was also associated with better overall survival out to 4 years of follow-up, reported Tait D. Shanafelt, MD, of Stanford (Calif.) University.

“This establishes ibrutinib-based therapy as the most effective treatment tested to date in this disease for untreated patients,” he said at a media briefing prior at the annual meeting of the American Society of Hematology.

The study results are likely to dethrone FCR as the most active chemoimmunotherapy regimen against CLL, Dr. Shanafelt said.

In the ECOG-ACRIN Cancer Research Group E1912 trial, 529 patients aged 70 or younger with previously untreated CLL were enrolled and randomly assigned on a 2:1 basis to either standard therapy with six cycles of FCR according to standard protocols (175 patients), or IR, with ibrutinib 420 mg daily for each cycle, and rituximab delivered 50 mg/m² intravenously on day 1 of cycle 2, and 325 mg/m² on day 2 of the same cycle, and 500 mg/m² on day 1 for all remaining cycles (354 patients).

From cycle 8 until progression, patients in the IR arm received daily ibrutinib 420 mg.

Dr. Shanafelt presented results from both an intention-to-treat analysis and a per-protocol analysis excluding 22 patients in the IR arm and 9 patients in the FCR arm who were randomized but later found not to meet eligibility criteria.

After a mean follow-up of 34 months, there were 37 PFS events in the IR arm, compared with 40 events in the FCR arm in an intention-to-treat analysis. The difference translated into a hazard ratio for progression of 0.35 with IR (P less than .00001).

The results were similar in the per-protocol analysis, with an HR of 0.32 favoring IR (P less than .00001).*

There were four deaths in the IR arm, compared with 10 in the FCR arm at the time of the data lock, translating into a hazard ratio (HR) for overall survival of 0.17 (P less than .0003) in the intention-to-treat analysis, and 0.13 in the per-protocol analysis (P less than .0001).

Dr. Shanafelt noted that although the overall number of deaths was relatively small, there were twice as many patients enrolled in the IR arm as in the FCR arm, meaning that the rate of deaths in the FCR arm was fivefold higher than in the IR arm.

In a subgroup analysis of PFS, IR was superior to FCR regardless of patient age, sex, performance status, disease stage, or the presence or absence of the 11q23.3 deletion.

PFS was also significantly better with IR in patients with unmutated immunoglobulin heavy chain variable (IGHV) regions (HR 0.26, P less than .00001), but not in patients with mutated IGHV.*

Grade 3 or greater treatment-related adverse events occurred in 58.5% of patients in the IR arm, compared with 72.1% of patients in the FCR arm. Specific events that occurred significantly less often with IR included neutropenia (22.7% vs. 43.7%), anemia (2.6% vs. 12.0%), thrombocytopenia (2.9% vs. 13.9%), any infection (7.1% vs. 19.0%), and neutropenic fever (2.3% vs. 15.8%; P less than .001 for all comparisons).

Events that occurred more frequently with IR than FCR included atrial fibrillation (2.9% vs. 0%, P = .04), and hypertension (7.4% vs. 1.9%, P = .01).

Dr. Shanafelt acknowledged that one possible barrier to the IR regimen is cost; the monthly cost of ibrutinib maintenance is about $10,000, he said, although he noted that cost considerations were not studied in the trial.

“Future trials testing novel agent combinations to see if we can eliminate the need for chronic therapy should be pursued,” he said.

The trial was sponsored by the National Cancer Institute with additional support from Pharmacyclics. Dr. Shanafelt reported patents and royalties from the Mayo Clinic, and research funding from Celgene, GlaxoSmithKline, Genentech, Abbvie, Pharmacyclics, and Janssen.

SOURCE: Shanafelt TD et al. ASH 2018, Abstract LBA-4.

*Correction, 12/12/2018: An earlier version of this story misstated the P value in two comparisons.

SAN DIEGO – It was banner year for new hematology drug approvals, according to R. Angelo de Claro, MD, of the Food and Drug Administration.

So far in 2018 there have been 32 new malignant hematology and nonmalignant hematology drug approvals by the FDA, including 12 first-time approvals, 5 new biosimilars, and 15 new indications for previously approved drugs, Dr. de Claro, clinical team leader in the FDA’s division of hematology products in Silver Spring, Md., said during an overview of the approvals at the annual meeting of the American Society of Hematology.

These include six new approvals for first-line treatment, and eight for pediatric indications, he said.

Highlights were discussed at two ASH-FDA joint symposia at the meeting, including one focused on the malignant hematology approvals, and another on the nonmalignant hematology approvals. In a video interview, Dr. de Claro provides some additional insight into their importance and about what might lie ahead.

“I think what’s exciting is that you have drug development occurring in more common conditions such as chronic lymphocytic leukemia, as well as in rare conditions, including hairy cell leukemia – and the first-ever approval in hemophagocytic lymphohistiocytosis,” he said. “It’s been very busy at the FDA; stay tuned ... the year’s not done yet. There could be more coming and we certainly anticipate more applications in the future.”

Dr. de Claro is an FDA employee. He reported having no other relevant disclosures.

[email protected]

SAN DIEGO – It was banner year for new hematology drug approvals, according to R. Angelo de Claro, MD, of the Food and Drug Administration.

So far in 2018 there have been 32 new malignant hematology and nonmalignant hematology drug approvals by the FDA, including 12 first-time approvals, 5 new biosimilars, and 15 new indications for previously approved drugs, Dr. de Claro, clinical team leader in the FDA’s division of hematology products in Silver Spring, Md., said during an overview of the approvals at the annual meeting of the American Society of Hematology.

These include six new approvals for first-line treatment, and eight for pediatric indications, he said.

Highlights were discussed at two ASH-FDA joint symposia at the meeting, including one focused on the malignant hematology approvals, and another on the nonmalignant hematology approvals. In a video interview, Dr. de Claro provides some additional insight into their importance and about what might lie ahead.

“I think what’s exciting is that you have drug development occurring in more common conditions such as chronic lymphocytic leukemia, as well as in rare conditions, including hairy cell leukemia – and the first-ever approval in hemophagocytic lymphohistiocytosis,” he said. “It’s been very busy at the FDA; stay tuned ... the year’s not done yet. There could be more coming and we certainly anticipate more applications in the future.”

Dr. de Claro is an FDA employee. He reported having no other relevant disclosures.

[email protected]

SAN DIEGO – It was banner year for new hematology drug approvals, according to R. Angelo de Claro, MD, of the Food and Drug Administration.

So far in 2018 there have been 32 new malignant hematology and nonmalignant hematology drug approvals by the FDA, including 12 first-time approvals, 5 new biosimilars, and 15 new indications for previously approved drugs, Dr. de Claro, clinical team leader in the FDA’s division of hematology products in Silver Spring, Md., said during an overview of the approvals at the annual meeting of the American Society of Hematology.

These include six new approvals for first-line treatment, and eight for pediatric indications, he said.

Highlights were discussed at two ASH-FDA joint symposia at the meeting, including one focused on the malignant hematology approvals, and another on the nonmalignant hematology approvals. In a video interview, Dr. de Claro provides some additional insight into their importance and about what might lie ahead.

“I think what’s exciting is that you have drug development occurring in more common conditions such as chronic lymphocytic leukemia, as well as in rare conditions, including hairy cell leukemia – and the first-ever approval in hemophagocytic lymphohistiocytosis,” he said. “It’s been very busy at the FDA; stay tuned ... the year’s not done yet. There could be more coming and we certainly anticipate more applications in the future.”

Dr. de Claro is an FDA employee. He reported having no other relevant disclosures.

[email protected]

SAN DIEGO – A recurrent mutation in BCL2, the therapeutic target of venetoclax (Venclexta), appears to be a major contributor to drug resistance in patients with chronic lymphocytic leukemia (CLL), investigators reported.

The mutation has been detected in some patients with CLL up to 2 years before resistance to venetoclax actually develops, said lead author Piers Blombery, MBBS, from the Peter MacCallum Cancer Center in Melbourne.

“We have identified the first acquired BCL2 mutation developed in patients clinically treated with venetoclax,” he said in a late-breaking oral abstract session at the annual meeting of the American Society of Hematology.

The mutation, which the investigators have labeled BCL2 Gly101Val, “is a recurrent and frequent mediator of resistance and may be detected years before clinical relapse occurs,” he added.

The paper was published online in Cancer Discovery (2018 Dec 4. doi: 10.1158/2159-8290.CD-18-1119) to coincide with the presentation at ASH.

Despite the demonstrated efficacy of venetoclax as continuous therapy in patients with relapsed or refractory CLL, the majority of patients experience disease progression, prompting the investigators to explore molecular mechanisms of secondary resistance.

To do this, they analyzed paired samples from 15 patients with CLL, enrolled in clinical trials of venetoclax, collected both before the start of venetoclax therapy and at the time of disease progression.

In seven of the patients, they identified a novel mutation that showed up at the time of progression, but was absent from the pre-venetoclax samples. The mutation first became detectable from about 19 to 42 months after the start of therapy and preceded clinical progression by as much as 25 months, the investigators found.

They pinned the mutation down to the BH3-binding groove on BCL2, the same molecular site targeted by venetoclax. They found that the mutation was not present in samples from 96 patients with venetoclax-naive CLL nor in any other B-cell malignancies. Searches for references to the mutation in both a cancer database (COSMIC) and a population database (gnomAD) came up empty.

In other experiments, they determined that cell lines overexpressing BCL2 Gly101Val are resistant to venetoclax, and that in the presence of venetoclax in vitro, BCL2 Gly101Val-expressing cells have a growth advantage, compared with wild type cells.

Additionally, they showed that the mutation results in impaired venetoclax binding in vitro.

“BCL2 Gly101Val is observed subclonally, implicating multiple mechanisms of venetoclax resistance in the same patient,” Dr. Blombery said.

In an interview, Dr. Blombery said that the identification of the resistance mutation is a strong rationale for using combination therapy to treat patients with relapsed or refractory CLL to help prevent or attenuate selection pressures that lead to resistance.

The investigators were supported by the Wilson Center for Lymphoma Genomics, Snowdome Foundation, National Health Medical Research Council, Leukemia and Lymphoma Society, Leukemia Foundation, Cancer Council of Victoria, and Australian Cancer Research Foundation. Dr. Blombery reported having no relevant disclosures.

SOURCE: Blombery P et al. ASH 2018, Abstract LBA-7.

SAN DIEGO – A recurrent mutation in BCL2, the therapeutic target of venetoclax (Venclexta), appears to be a major contributor to drug resistance in patients with chronic lymphocytic leukemia (CLL), investigators reported.

The mutation has been detected in some patients with CLL up to 2 years before resistance to venetoclax actually develops, said lead author Piers Blombery, MBBS, from the Peter MacCallum Cancer Center in Melbourne.

“We have identified the first acquired BCL2 mutation developed in patients clinically treated with venetoclax,” he said in a late-breaking oral abstract session at the annual meeting of the American Society of Hematology.

The mutation, which the investigators have labeled BCL2 Gly101Val, “is a recurrent and frequent mediator of resistance and may be detected years before clinical relapse occurs,” he added.

The paper was published online in Cancer Discovery (2018 Dec 4. doi: 10.1158/2159-8290.CD-18-1119) to coincide with the presentation at ASH.

Despite the demonstrated efficacy of venetoclax as continuous therapy in patients with relapsed or refractory CLL, the majority of patients experience disease progression, prompting the investigators to explore molecular mechanisms of secondary resistance.

To do this, they analyzed paired samples from 15 patients with CLL, enrolled in clinical trials of venetoclax, collected both before the start of venetoclax therapy and at the time of disease progression.

In seven of the patients, they identified a novel mutation that showed up at the time of progression, but was absent from the pre-venetoclax samples. The mutation first became detectable from about 19 to 42 months after the start of therapy and preceded clinical progression by as much as 25 months, the investigators found.

They pinned the mutation down to the BH3-binding groove on BCL2, the same molecular site targeted by venetoclax. They found that the mutation was not present in samples from 96 patients with venetoclax-naive CLL nor in any other B-cell malignancies. Searches for references to the mutation in both a cancer database (COSMIC) and a population database (gnomAD) came up empty.

In other experiments, they determined that cell lines overexpressing BCL2 Gly101Val are resistant to venetoclax, and that in the presence of venetoclax in vitro, BCL2 Gly101Val-expressing cells have a growth advantage, compared with wild type cells.

Additionally, they showed that the mutation results in impaired venetoclax binding in vitro.

“BCL2 Gly101Val is observed subclonally, implicating multiple mechanisms of venetoclax resistance in the same patient,” Dr. Blombery said.

In an interview, Dr. Blombery said that the identification of the resistance mutation is a strong rationale for using combination therapy to treat patients with relapsed or refractory CLL to help prevent or attenuate selection pressures that lead to resistance.

The investigators were supported by the Wilson Center for Lymphoma Genomics, Snowdome Foundation, National Health Medical Research Council, Leukemia and Lymphoma Society, Leukemia Foundation, Cancer Council of Victoria, and Australian Cancer Research Foundation. Dr. Blombery reported having no relevant disclosures.

SOURCE: Blombery P et al. ASH 2018, Abstract LBA-7.

SAN DIEGO – A recurrent mutation in BCL2, the therapeutic target of venetoclax (Venclexta), appears to be a major contributor to drug resistance in patients with chronic lymphocytic leukemia (CLL), investigators reported.

The mutation has been detected in some patients with CLL up to 2 years before resistance to venetoclax actually develops, said lead author Piers Blombery, MBBS, from the Peter MacCallum Cancer Center in Melbourne.

“We have identified the first acquired BCL2 mutation developed in patients clinically treated with venetoclax,” he said in a late-breaking oral abstract session at the annual meeting of the American Society of Hematology.

The mutation, which the investigators have labeled BCL2 Gly101Val, “is a recurrent and frequent mediator of resistance and may be detected years before clinical relapse occurs,” he added.

The paper was published online in Cancer Discovery (2018 Dec 4. doi: 10.1158/2159-8290.CD-18-1119) to coincide with the presentation at ASH.

Despite the demonstrated efficacy of venetoclax as continuous therapy in patients with relapsed or refractory CLL, the majority of patients experience disease progression, prompting the investigators to explore molecular mechanisms of secondary resistance.

To do this, they analyzed paired samples from 15 patients with CLL, enrolled in clinical trials of venetoclax, collected both before the start of venetoclax therapy and at the time of disease progression.

In seven of the patients, they identified a novel mutation that showed up at the time of progression, but was absent from the pre-venetoclax samples. The mutation first became detectable from about 19 to 42 months after the start of therapy and preceded clinical progression by as much as 25 months, the investigators found.

They pinned the mutation down to the BH3-binding groove on BCL2, the same molecular site targeted by venetoclax. They found that the mutation was not present in samples from 96 patients with venetoclax-naive CLL nor in any other B-cell malignancies. Searches for references to the mutation in both a cancer database (COSMIC) and a population database (gnomAD) came up empty.

In other experiments, they determined that cell lines overexpressing BCL2 Gly101Val are resistant to venetoclax, and that in the presence of venetoclax in vitro, BCL2 Gly101Val-expressing cells have a growth advantage, compared with wild type cells.

Additionally, they showed that the mutation results in impaired venetoclax binding in vitro.

“BCL2 Gly101Val is observed subclonally, implicating multiple mechanisms of venetoclax resistance in the same patient,” Dr. Blombery said.

In an interview, Dr. Blombery said that the identification of the resistance mutation is a strong rationale for using combination therapy to treat patients with relapsed or refractory CLL to help prevent or attenuate selection pressures that lead to resistance.

The investigators were supported by the Wilson Center for Lymphoma Genomics, Snowdome Foundation, National Health Medical Research Council, Leukemia and Lymphoma Society, Leukemia Foundation, Cancer Council of Victoria, and Australian Cancer Research Foundation. Dr. Blombery reported having no relevant disclosures.

SOURCE: Blombery P et al. ASH 2018, Abstract LBA-7.

SAN DIEGO – Ibrutinib alone or in combination with rituximab resulted in superior progression-free survival (PFS) when compared with bendamustine plus rituximab in the randomized, phase 3 Alliance A041202 trial of older patients with previously untreated chronic lymphocytic leukemia (CLL).

Sharon Worcester/MDedge News

[email protected]

SOURCE: Woyach JA et al. ASH 2018, Abstract 6.

SAN DIEGO – Ibrutinib alone or in combination with rituximab resulted in superior progression-free survival (PFS) when compared with bendamustine plus rituximab in the randomized, phase 3 Alliance A041202 trial of older patients with previously untreated chronic lymphocytic leukemia (CLL).

Sharon Worcester/MDedge News

[email protected]

SOURCE: Woyach JA et al. ASH 2018, Abstract 6.

SAN DIEGO – Ibrutinib alone or in combination with rituximab resulted in superior progression-free survival (PFS) when compared with bendamustine plus rituximab in the randomized, phase 3 Alliance A041202 trial of older patients with previously untreated chronic lymphocytic leukemia (CLL).

Sharon Worcester/MDedge News

[email protected]

SOURCE: Woyach JA et al. ASH 2018, Abstract 6.

The presence or absence in tumor cells of cortactin, a cytoskeleton-remodeling adapter protein, may be a marker to help pathologists distinguish between chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL), investigators suggest.

A study of cortactin expression in tumor samples from patients with B-cell CLL, MCL, and other hematologic malignancies showed that while cortactin was present in 14 of 17 CLL samples, it was not expressed on any of 16 MCL samples, reported Marco Pizzi, MD, PhD, from the University of Padova (Italy) and his colleagues.

“In particular, cortactin may contribute to the differential diagnosis between CLL and MCL, two neoplasms with similar histological features but very different clinical outcome. Further studies are needed to clarify the molecular mechanisms of deranged cortactin expression in MCL and CLL and to investigate any possible relationship between cortactin status and the biological features of these lymphomas,” they wrote in Human Pathology.

Overexpression of cortactin has been reported in several solid tumors, and increased expression of CTTN, the gene encoding for cortactin, has been associated with aggressive, poor prognosis disease, the investigators noted.

To characterize cortactin expression in lymphoid and hematopoietic cells and detect potential associations between cortactin and virulence of hematologic malignancies, the investigators performed immunohistochemical analysis on samples from 131 patients treated at their center. The samples included 17 cases of CLL, 16 of MCL, 25 of follicular lymphoma (FL), 30 of marginal zone lymphoma (MZL), 10 of hairy cell leukemia, three of splenic diffuse red pulp small B-cell lymphomas (SDRPBL), and 30 of diffuse large B-cell lymphoma (DLBCL).

They found that cortactin was expressed in 14 of the 17 CLL samples, all 10 of the HCL samples, and 22 of the 30 DLBCL samples. In contrast, there was no cortactin expression detected in any of either 16 MCL or three SDRPBL samples. The researchers found that 13 of 30 MZL samples had low-level staining. In FL, cortactin was expressed in 2 of the samples but in the remaining 23 cases the researchers found only scattered cortactin-positive lymphoid elements of non–B-cell lineage.

The investigators also found that cortactin expression in CLL correlated with other CLL-specific markers, and found that expression of two or more of the markers had 89.1% sensitivity, 100% specificity, a 100% positive predictive value, and 90.5% negative predictive value for a diagnosis of CLL.

In addition, they saw that the immunohistochemical results were similar to those for CTTN gene expression assessed by in silico analysis.

The investigators noted that CLL and MCL are challenging to differentiate from one another because of morphologic similarities and partially overlapping immunophenotypes.

“In this context, cortactin expression would strongly sustain a diagnosis of CLL over MCL, particularly in association with other CLL markers (i.e., LEF1 and CD200),” they wrote.

The study was internally supported. The authors declared no conflicts of interest.

SOURCE: Pizzi M et al. Hum Pathol. 2018 Nov 17. doi: 10.1016/j.humpath.2018.10.038.
 

The presence or absence in tumor cells of cortactin, a cytoskeleton-remodeling adapter protein, may be a marker to help pathologists distinguish between chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL), investigators suggest.

A study of cortactin expression in tumor samples from patients with B-cell CLL, MCL, and other hematologic malignancies showed that while cortactin was present in 14 of 17 CLL samples, it was not expressed on any of 16 MCL samples, reported Marco Pizzi, MD, PhD, from the University of Padova (Italy) and his colleagues.

“In particular, cortactin may contribute to the differential diagnosis between CLL and MCL, two neoplasms with similar histological features but very different clinical outcome. Further studies are needed to clarify the molecular mechanisms of deranged cortactin expression in MCL and CLL and to investigate any possible relationship between cortactin status and the biological features of these lymphomas,” they wrote in Human Pathology.

Overexpression of cortactin has been reported in several solid tumors, and increased expression of CTTN, the gene encoding for cortactin, has been associated with aggressive, poor prognosis disease, the investigators noted.

To characterize cortactin expression in lymphoid and hematopoietic cells and detect potential associations between cortactin and virulence of hematologic malignancies, the investigators performed immunohistochemical analysis on samples from 131 patients treated at their center. The samples included 17 cases of CLL, 16 of MCL, 25 of follicular lymphoma (FL), 30 of marginal zone lymphoma (MZL), 10 of hairy cell leukemia, three of splenic diffuse red pulp small B-cell lymphomas (SDRPBL), and 30 of diffuse large B-cell lymphoma (DLBCL).

They found that cortactin was expressed in 14 of the 17 CLL samples, all 10 of the HCL samples, and 22 of the 30 DLBCL samples. In contrast, there was no cortactin expression detected in any of either 16 MCL or three SDRPBL samples. The researchers found that 13 of 30 MZL samples had low-level staining. In FL, cortactin was expressed in 2 of the samples but in the remaining 23 cases the researchers found only scattered cortactin-positive lymphoid elements of non–B-cell lineage.

The investigators also found that cortactin expression in CLL correlated with other CLL-specific markers, and found that expression of two or more of the markers had 89.1% sensitivity, 100% specificity, a 100% positive predictive value, and 90.5% negative predictive value for a diagnosis of CLL.

In addition, they saw that the immunohistochemical results were similar to those for CTTN gene expression assessed by in silico analysis.

The investigators noted that CLL and MCL are challenging to differentiate from one another because of morphologic similarities and partially overlapping immunophenotypes.

“In this context, cortactin expression would strongly sustain a diagnosis of CLL over MCL, particularly in association with other CLL markers (i.e., LEF1 and CD200),” they wrote.

The study was internally supported. The authors declared no conflicts of interest.

SOURCE: Pizzi M et al. Hum Pathol. 2018 Nov 17. doi: 10.1016/j.humpath.2018.10.038.
 

The presence or absence in tumor cells of cortactin, a cytoskeleton-remodeling adapter protein, may be a marker to help pathologists distinguish between chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL), investigators suggest.

A study of cortactin expression in tumor samples from patients with B-cell CLL, MCL, and other hematologic malignancies showed that while cortactin was present in 14 of 17 CLL samples, it was not expressed on any of 16 MCL samples, reported Marco Pizzi, MD, PhD, from the University of Padova (Italy) and his colleagues.

“In particular, cortactin may contribute to the differential diagnosis between CLL and MCL, two neoplasms with similar histological features but very different clinical outcome. Further studies are needed to clarify the molecular mechanisms of deranged cortactin expression in MCL and CLL and to investigate any possible relationship between cortactin status and the biological features of these lymphomas,” they wrote in Human Pathology.

Overexpression of cortactin has been reported in several solid tumors, and increased expression of CTTN, the gene encoding for cortactin, has been associated with aggressive, poor prognosis disease, the investigators noted.

To characterize cortactin expression in lymphoid and hematopoietic cells and detect potential associations between cortactin and virulence of hematologic malignancies, the investigators performed immunohistochemical analysis on samples from 131 patients treated at their center. The samples included 17 cases of CLL, 16 of MCL, 25 of follicular lymphoma (FL), 30 of marginal zone lymphoma (MZL), 10 of hairy cell leukemia, three of splenic diffuse red pulp small B-cell lymphomas (SDRPBL), and 30 of diffuse large B-cell lymphoma (DLBCL).

They found that cortactin was expressed in 14 of the 17 CLL samples, all 10 of the HCL samples, and 22 of the 30 DLBCL samples. In contrast, there was no cortactin expression detected in any of either 16 MCL or three SDRPBL samples. The researchers found that 13 of 30 MZL samples had low-level staining. In FL, cortactin was expressed in 2 of the samples but in the remaining 23 cases the researchers found only scattered cortactin-positive lymphoid elements of non–B-cell lineage.

The investigators also found that cortactin expression in CLL correlated with other CLL-specific markers, and found that expression of two or more of the markers had 89.1% sensitivity, 100% specificity, a 100% positive predictive value, and 90.5% negative predictive value for a diagnosis of CLL.

In addition, they saw that the immunohistochemical results were similar to those for CTTN gene expression assessed by in silico analysis.

The investigators noted that CLL and MCL are challenging to differentiate from one another because of morphologic similarities and partially overlapping immunophenotypes.

“In this context, cortactin expression would strongly sustain a diagnosis of CLL over MCL, particularly in association with other CLL markers (i.e., LEF1 and CD200),” they wrote.

The study was internally supported. The authors declared no conflicts of interest.

SOURCE: Pizzi M et al. Hum Pathol. 2018 Nov 17. doi: 10.1016/j.humpath.2018.10.038.