|The following article features coverage from the 2021 American Society of Hematology Annual Meeting. Click here to read more of Cancer Therapy Advisor’s conference coverage.|
Combination treatment with naratuximab emtansine and rituximab produces durable responses in patients with relapsed/refractory B-cell non-Hodgkin lymphoma (B-NHL), a phase 2 study suggests.
Naratuximab emtansine is the most advanced CD37-targeting antibody-drug conjugate in clinical development for relapsed/refractory diffuse large B-cell lymphoma (DLBCL) and other relapsed/refractory NHLs, said Moshe Y. Levy, MD, of Baylor Charles A. Sammons Cancer Center in Dallas, Texas.
Dr Levy presented the results with naratuximab emtansine and rituximab at the 2021 American Society of Hematology (ASH) Annual Meeting.
The phase 2 trial (ClinicalTrials.gov Identifier: NCT02564744) of the combination included 100 patients with relapsed/refractory B-NHLs who were not candidates for stem cell transplant and had received 1-6 prior lines of treatment.
Patients had DLBCL (n=80), follicular lymphoma (FL, n=14), or mantle cell lymphoma (MCL, n=6).
All 20 patients with FL/MCL and 50 patients with DLBCL received naratuximab emtansine every 3 weeks, given at 0.7 mg/kg on day 1 of a 21-day cycle, followed by rituximab at 375 mg/m2. The remaining 30 DLBCL patients received naratuximab emtansine every week — 0.4 mg/kg on day 1 and 0.2 mg/kg on days 8 and 15 — plus rituximab at 375 mg/m2 on day 1.
In the DLBCL cohort, 76 patients were evaluable for efficacy. The overall response rate (ORR) in this group was 44.7%, and the complete response (CR) rate was 31.6%.
Among DLBCL patients who received treatment every 3 weeks, the ORR was 50.0%, and the CR rate was 43.3%. Among patients who received treatment every week, the ORR was 50.0%, and the CR rate was 33.3%.
At a median follow-up of 19.4 months, the median duration of response was not reached in the DLBCL cohort. Two-thirds of responders had a response lasting more than 12 months.
Among the 14 patients with FL, the ORR was 57.1%. There were 5 patients with a CR, 3 with a partial response, 3 with stable disease, and 3 with progressive disease.
At a median follow-up of 21.8 months, the median duration of response was not reached in patients with FL.
Among the 6 patients with MCL, 4 patients were evaluable for efficacy. Two had CRs, and 2 had progressive disease.
In the overall cohort, the most common grade 3-4 treatment-emergent adverse events (TEAEs) were neutropenia (54%), leukopenia (19%), lymphopenia (17%), and thrombocytopenia (12%).
TEAEs leading to naratuximab emtansine dose reductions occurred in 6% of patients, and TEAEs leading to discontinuation of study treatment occurred in 8%.
Ten patients had grade 5 TEAEs, and 2 of them were considered related to naratuximab emtansine.
“The safety profile of nara plus rituximab was tolerable and manageable,” Dr Levy said. “Nara plus rituximab could certainly represent a new treatment option for relapsed/refractory non-Hodgkin lymphoma, especially relapsed/refractory DLBCL.”
Disclosures: This research was supported by Debiopharm International SA. Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
Read more of Cancer Therapy Advisor’s coverage of the ASH 2021 meeting by visiting the conference page.
Levy MY, Jagadeesh D, Popova Z, et al. Safety and efficacy of CD37-targeting naratuximab emtansine plus rituximab in diffuse large B-cell lymphoma and other non-Hodgkin’s B-cell lymphomas – A phase 2 study. Presented at ASH 2021; December 11-14, 2021. Abstract 526.