Phase 2 primary analysis results presented in ASH oral session demonstrated a 52% objective response rate (ORR), with 31% achieving a complete response (CR)

Results from a Phase 1 expansion cohort showed a 48% ORR and 30% CR in patients who had progressed on CAR-T

Additional exploratory data from the Phase 2 trial presented in an oral session showed an association between circulating tumor DNA (ctDNA) negativity and progression-free survival

TARRYTOWN, N.Y., Dec. 10, 2023 (GLOBE NEWSWIRE) -- Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) today announced new and updated data for odronextamab in patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). The data from the pivotal Phase 2 trial (ELM-2) and Phase 1 trial (ELM-1) were shared in several presentations – including two orals – at the 65th American Society of Hematology (ASH) Annual Meeting and Exposition from December 9 to 12 in San Diego, CA. Odronextamab is an investigational CD20xCD3 bispecific antibody designed to bridge CD20 on cancer cells with CD3-expressing T cells to facilitate local T-cell activation and cancer-cell killing.

“Diffuse large B-cell lymphoma has a high risk of relapse, which is why it is so critical to demonstrate continued disease control over the long term. The totality of the odronextamab data at ASH reinforces its potential as a promising treatment option for patients with this aggressive blood cancer,” said Sabarish Ram Ayyappan, M.D., medical director of hematologic malignancies, City of Hope Atlanta, and a trial investigator. “The primary analysis from the pivotal trial of odronextamab demonstrated impressive response rates, including in certain high-risk subgroups. Furthermore, these responses were durable and consistent with those seen in a Phase 1 trial in patients who had previously progressed on CAR-T therapy, a population with a very poor prognosis.”

As presented in an oral session, the primary Phase 2 analysis was performed by independent central review (ICR) among 127 DLBCL patients treated with odronextamab when all had the opportunity for ≥36 weeks of follow-up. Results were as follows:

• 52% objective response rate (ORR), with 31% achieving a complete response (CR).
• Responses were observed across high-risk subgroups, including those with International Prognosis Index (IPI) high-risk scores of 3 to 5, high-grade lymphoma that is double-hit and triple-hit, and transformed DLBCL.
• Median duration of response(DoR) was 10 months (95% confidence interval [CI]: 5 to 18 months), with a 30-month median duration of follow-up for efficacy evaluable patients (95% CI: 20 to 33 months). The median duration of CR was 18 months (95% CI: 10 months to not estimable [NE]).
• The most common adverse events (AE) in ≥30% patients were cytokine release syndrome (CRS; 55%), pyrexia (43%), anemia (39%) and neutropenia (31%).
• In 60 patients that received the recommended step-up regimen, 53% experienced CRS. All cases were resolved with supportive measures, with a median duration of 2 days (range: 1 to 7 days). Among these patients, 40% (n=24) had Grade 1 CRS, 12% (n=7) had Grade 2 CRS, and 2% (n=1) had Grade 3 CRS.
• No events of immune effector cell-associated neurotoxicity syndrome (ICANS) were reported.

An additional analysis from the Phase 1 trial demonstrated encouraging and durable antitumor activity with odronextamab in heavily pretreated patients who had progressed after CAR-T therapy. Median duration of exposure was 11 weeks (range: