Phase II ELM-2 exploratory analysis: CR dynamics with odronextamab in R/R FL

Results from an exploratory analysis of the phase II ELM-2 study (NCT03888105), evaluating odronextamab in 128 patients with relapsed/refractory (R/R) follicular lymphoma (FL), were published in HemaSphere by Luminari et al. The primary objective of this analysis was to assess complete response (CR) dynamics in patients with a CR.

Key data: At a median follow-up of 20.1 months, the overall response rate (ORR) was 80.5%, with 73.4% of patients achieving a CR. The median time to CR was 2.7 months and the median duration of CR (DoCR) was 25.1 months (95% confidence interval [CI], 20.5–not evaluable [NE]). Among patients with high-risk features, the median time to CR was the same as the overall population, and the median DoCR was 23.7 months (95% CI, 18.2–NE). Median progression-free survival (PFS) was 27.8 months (95% CI, 23.0–NE) in patients with a CR compared with 20.7 months (95% CI, 17.2–27.5) in the overall population. In total, 46.8% of patients with a CR for ≥9 months transitioned to once every 4 weeks (Q4W) dosing; among these patients, 79.5% maintained CR at their last available response assessment. The most common treatment-emergent adverse events (TEAEs) of any grade in patients with a CR were cytokine release syndrome (CRS; 56.4%), pyrexia (44.7%), and neutropenia (41.5%).

Key learning: Odronextamab produced durable CRs in patients with R/R FL, including those with high-risk features, supporting its potential as a long-term treatment option.