ABCL-439 Subcutaneous Epcoritamab With Gemcitabine + Oxaliplatin (GemOx) Induced High Response Rates in Patients With Relapsed or Refractory (R/R) Diffuse Large B-Cell Lymphoma (DLBCL) Ineligible for Autologous Stem Cell Transplant (ASCT)

Context: Patients with R/R DLBCL who fail or are ineligible for ASCT have poor outcomes with standard palliative chemotherapy. Epcoritamab is a subcutaneously administered CD3xCD20 bispecific antibody that demonstrated substantial antitumor activity in R/R DLBCL. Objective: Evaluate the safety and efficacy of epcoritamab + GemOx in patients with R/R DLBCL who are ineligible for ASCT in arm 5 of a phase 1/2, open-label trial (EPCORE NHL-2; NCT04663347). Patients: Adults with R/R CD20+ DLBCL who failed or were ineligible for ASCT were included. As of December 1, 2021, 27 patients (median age, 71 y) were treated. Interventions: Patients received subcutaneous epcoritamab (QW, cycle [C] 1–3; Q2W, C4–9; Q4W, C≥10) and GemOx (Q2W, C1–4) until disease progression or unacceptable toxicity (28 d/C). Step-up dosing and prophylactic corticosteroids were required. Results: Of the 27 patients (epcoritamab 24 mg, n=3; 48 mg, n=24), most were stage IV (56%), primary refractory (56%), and/or refractory to last therapy (70%). Median number of prior therapies was 2 (range, 1–13), and median follow-up was 6.0 mo (range, 1.0–11.1), with treatment ongoing in 16 patients (59%). The most common treatment-emergent AEs were CRS (70%), thrombocytopenia (70%), neutropenia (56%), anemia (52%), and infections (52%). CRS events were all grade (G) 1–2, with most cases in C1; all cases resolved. One patient had ICANS (G3). Six patients (22%) had G5 AEs: unrelated to epcoritamab by the investigator in 4 patients; epcoritamab contribution could not be ruled out in 2 patients. The overall response rate for the 25 efficacy-evaluable patients was 92% by PET-CT; 60% had a complete metabolic response (CMR), and 32% had a partial metabolic response (PMR). At data cutoff, the longest duration of response was 6.9 mo. All 3 patients with prior CAR T remained on treatment and in response (2 had CMR and 1 had PMR). Conclusions: In this R/R population with high unmet need, no unexpected safety findings were observed for epcoritamab + GemOx. These initial data are encouraging and warrant further clinical evaluation. Funding: This study was funded by Genmab A/S and AbbVie.