Subcutaneous epcoritamab monotherapy in Japanese patients with relapsed or refractory follicular lymphoma: primary results of the EPCORE NHL-3 trial.

An unmet need exists for patients with relapsed or refractory (R/R) follicular lymphoma (FL) whose disease remains incurable. Epcoritamab, a subcutaneous CD3xCD20 bispecific antibody, is approved for R/R FL and different types of R/R large B-cell lymphoma after ≥2 prior lines of therapy (pLOT) in the US, Europe, and Japan. Regional data are critical to contextualize global trial data. In the Japan-specific EPCORE NHL-3 trial (phase 1/2), 21 adults with R/R FL and ≥2 pLOT received subcutaneous epcoritamab (two step-up doses, then 48-mg full doses) until progression. Median follow-up was 21.2 months. Responses were frequent and deep (overall response rate, 95.2%; complete response rate, 76.2%), including in high-risk subgroups, as well as durable. Safety was manageable; cytokine release syndrome events had predictable timing and were mostly low grade, and no fatal treatment-emergent adverse events occurred. These results support epcoritamab as a new treatment option for Japanese patients with R/R FL.Clinical trial registration numbers: NCT04542824; JapicCTI-205408; jRCT2080225312.