Trial in Progress: Phase 1 Trial Evaluating the Safety and Tolerability of Odronextamab in Combination with Cemiplimab in Relapsed/Refractory Aggressive B‑Cell Non-Hodgkin Lymphoma

Background and Significance

CD20×CD3 bispecific antibodies (bsAbs) have emerged as an important immunotherapeutic approach for relapsed/refractory (R/R) B-cell non-Hodgkin lymphoma (B-NHL). These agents have shown compelling efficacy in indolent B-NHL, with the CD20×CD3 bsAb odronextamab demonstrating 75% complete response (CR) rates and encouraging durability of responses (median duration of response [DoR], 20.5 months) in heavily pretreated patients with R/R follicular lymphoma in the ELM-2 study (Kim TM, et al. ASH. 2022). In comparison, patients with R/R diffuse large B-cell lymphoma who were treated with odronextamab in the same study demonstrated a CR rate of 31%, and median DoR was 10.2 months (Kim WS, et al. ASH. 2022). These data indicate an unmet need for treatment strategies that can improve the depth and durability of responses in patients with aggressive R/R B-NHL.

Combination therapy with drugs that complement the mechanism of action of CD20×CD3 bsAbs may provide an opportunity to address this unmet need. Cemiplimab is a human immunoglobulin G4 (IgG4) monoclonal antibody directed against programmed cell death protein 1 (PD-1), blocking PD-1- and programmed cell death ligand 1 (PD-L1)-driven inhibitory T-cell signaling. Combining odronextamab and cemiplimab provides an attractive therapeutic opportunity to improve anti-tumor efficacy while restricting T-cell exhaustion, and preliminary results for this combination provided proof of concept, with evidence of clinical activity and manageable tolerability in patients with B-lymphoid malignancies (n=12; Topp MS, et al. ASH. 2017). Here, we investigate whether the addition of cemiplimab to odronextamab can improve the depth and durability of response in patients with previously treated aggressive B-NHL.

Study Design and Methods

This is a Phase 1, open-label, multicenter, dose-escalation and -expansion study that will take place at up to 28 sites globally (NCT02651662). Intravenous (IV) odronextamab is administered in 21-day cycles, initially as monotherapy and with step-up dosing during Cycle (C) 1 to mitigate the risk of cytokine release syndrome (Figure). Full-dose odronextamab is administered on Day (D) 1, D8 and D15 of C2–C4, and then on D15 of each cycle during maintenance (C5 onwards) until disease progression or treatment discontinuation. IV cemiplimab starts on C2D15 at the specified dose level (DL1–DL7) and is administered on D15 of subsequent cycles. The dose-limiting toxicity (DLT) period is 28 days from the start of cemiplimab administration. At the end of dose escalation, a regimen will be selected for further investigation in dose expansion.

Approximately 60 patients will be enrolled. Patients will be aged ≥18 years with aggressive CD20+ B-NHL that is R/R after ≥2 lines of systemic therapy containing an anti-CD20 antibody and an alkylating agent. Patients must have measurable disease, Eastern Cooperative Oncology Group performance score (ECOG PS) ≤1, and adequate bone marrow and organ function. Exclusion criteria include primary central nervous system lymphoma, prior allogeneic stem cell transplantation, autoimmune disease, prior adverse events from anti-PD-1/PD-L1 therapy, and uncontrolled infections.

Primary endpoints are safety, tolerability, DLTs, and to determine the recommended Phase 2 dose of the combination regimen of odronextamab and cemiplimab. Secondary endpoints include pharmacokinetics, immunogenicity, and preliminary anti-tumor activity (overall response rate, CR rate, and DoR, according to the Lugano classification). There are no formal hypotheses for this study and analyses will be descriptive in nature.