O13-3 Subcutaneous epcoritamab in Japanese patients with relapsed/refractory diffuse large B-cell lymphoma: EPCORE NHL-3 data

Epcoritamab, a subcutaneously (SC) administered CD3xCD20 bispecific antibody, has shown deep, durable antitumor activity and manageable safety in patients (pts) with B-cell non-Hodgkin lymphomas (EHA 2022, abstract LB2364). We present data from arm 1 of the EPCORE NHL-3 phase 1/2 trial (NCT04542824) evaluating epcoritamab monotherapy in Japanese pts with relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL). Pts with R/R CD20+ DLBCL received SC epcoritamab 48 mg in 28-d cycles (QW, cycle [C] 1–3; Q2W, C4–9; Q4W, C≥10) until disease progression or unacceptable toxicity. Step-up dosing (day [D] 1, 0.16 mg; D8, 0.8 mg; D15, 48 mg) and corticosteroids were required in C1 for CRS mitigation. As of January 31, 2022, 36 pts with R/R DLBCL (median age, 69 y) had received epcoritamab. The median number of prior treatment (Tx) lines was 3 (range, 2–8); 56% had primary refractory disease and 81% were refractory to their last Tx line. Tx was ongoing in 14/36 (39%) pts, with a median follow-up of 8.4 mo (range, 1.5+ to 12.0). CRS (83%), injection-site reactions (58%), decreased neutrophil count (36%), hypokalemia (28%), and decreased lymphocyte count (25%) were the most common Tx-emergent AEs. Most CRS events occurred following the first full dose on C1D15 and were low grade (grade [G] 1, 18 pts; G2, 9 pts; G3, 3 pts; no G4–5); 10 pts received tocilizumab. All CRS events resolved (median time to resolution, 5 d); no pts discontinued Tx due to CRS. The 1 ICANS event (G1) resolved. Among 36 efficacy-evaluable pts, overall response rate and complete metabolic response rate (independent review committee, Lugano 2014) were 56% and 44%, respectively. Median duration of response and median overall survival were not reached. SC epcoritamab showed high response rates and a manageable safety profile in Japanese pts with highly refractory and heavily pretreated disease, supporting further evaluation of epcoritamab in pts with R/R DLBCL.