A phase 1/2 study of favezelimab in combination with pembrolizumab for heavily pretreated anti–PD-1–refractory classical Hodgkin lymphoma (cHL): An updated analysis.
Authors: John Timmerman, David Lavie, Nathalie A. Johnson, Abraham Avigdor, Borchmann Peter, Charalambos Andreadis, Ali Bazargan, Gareth P. Gregory, Colm Keane, Inna Torzan, Vladan Vucinic, Pier Luigi Zinzani, Rachel Marceau West, Pallavi Pillai, Patricia Marinello, Alex Francisco Herrera
Journal: Journal of Clinical Oncology (2024)

7056 Background: PD-1 inhibitors are standard of care for relapsed or refractory (R/R) cHL, but patients (pts) often progress after anti–PD-1 therapy. The immune checkpoint receptor lymphocyte-activation gene 3 (LAG-3) is proposed to contribute to anti–PD-1 resistance. In a phase 1/2 study (NCT03598608) evaluating favezelimab (anti–LAG-3) plus pembrolizumab (anti–PD-1) for R/R hematologic malignancies, the combination provided antitumor activity and manageable safety in pts with heavily pretreated anti–PD-1–refractory cHL (cohort 2). Updated results after additional follow-up are presented. Methods: Eligible pts were aged ≥18 years with R/R cHL; prior treatment with or ineligibility for autologous stem cell transplantation or no response to salvage chemotherapy; an ECOG performance status of 0 or 1; and disease progression after ≥2 doses of anti–PD-1–based therapy and within 12 weeks of the last dose of anti–PD-1 therapy. The study comprised a safety lead-in (pembrolizumab 200 mg IV Q3W + favezelimab 200-mg starting dose, then dose escalation to 800 mg IV Q3W per a modified toxicity probability interval design) and a dose expansion phase (pembrolizumab + favezelimab at the established recommended phase 2 dose of 800 mg Q3W for ≤35 cycles). Primary end point was safety. ORR per IWG 2007 criteria by investigator review was a secondary end point. DOR and PFS per IWG 2007 criteria by investigator review and OS were exploratory. Results: Cohort 2 enrolled 34 pts. Median time from first dose to data cutoff (August 15, 2023) was 40.7 months (range, 20.4-54.8). Treatment-related AEs occurred in 28 pts (82%); the most common (≥15%) were hypothyroidism (18%), nausea (18%), and fatigue (15%). Grade 3 or 4 treatment-related AEs occurred in 6 pts (18%). Discontinuation due to treatment-related AEs occurred in 6 pts (18%). No deaths due to treatment-related AEs were reported. AEs of clinical interest occurred in 17 pts (50%); 2 pts (6%) had grade 3 events (encephalitis, hepatitis) and 1 pt (3%) had a grade 4 event (type 1 diabetes mellitus). ORR was 29% (10/34; 95% CI, 15-48), with 3 (9%) complete responses and 7 (21%) partial responses. ORR was 35% (6/17; 95% CI, 14-62) in pts with anti–PD-1 and 24% (4/17; 95% CI, 7-50) in pts with non–anti–PD-1 as most recent therapy. Median DOR was 21.9 months (range, 0.0+ to 26.1+) and an estimated 17% of responders remained in response at 24 months. Median PFS was 9.7 months (95% CI, 5.1-14.7); 24-month PFS rate was 21%. Median OS was 39.0 months (95% CI, 25.7-not reached); 24-month OS rate was 73%. Conclusions: After additional follow-up, favezelimab + pembrolizumab continued to demonstrate manageable safety and antitumor activity in pts with heavily pretreated anti–PD-1–refractory cHL. The phase 3 KEYFORM-008 study (NCT05508867) will evaluate a coformulation of favezelimab and pembrolizumab in pts with anti–PD-1–refractory cHL. Clinical trial information: NCT03598608 .