Abstract

Chimeric antigen receptor (CAR) T-cell therapies have shown clinical benefit for patients with relapsed/refractory (R/R) large B-cell lymphoma (LBCL), yet approximately 60% of patients do not respond or eventually relapse. We investigated the safety and feasibility of the CD19-directed CAR T-cell therapy axicabtagene ciloleucel (axi-cel) in combination with the 4-1BB agonist antibody utomilumab as an approach to improve efficacy of CAR T-cell therapy.In Phase 1 of the single-arm ZUMA-11 trial, patients with R/R LBCL received a single axi-cel infusion (target dose: 2×106 cells/kg) plus utomilumab 10-200 mg intravenously every 4 weeks for up to 6 months in a dose-escalation design. The primary endpoint was incidence of dose-limiting toxicities (DLTs) with utomilumab. Key secondary endpoints were safety, antitumor activity, pharmacokinetics, and pharmacodynamics.No DLTs were observed among patients treated with axi-cel and utomilumab (n=12). Grade =3 adverse events occurred in 10 patients (83%); none were Grade =3 cytokine release syndrome or neurologic events. The objective response rate was 75% and 7 patients (58%) had a complete response. Peak CAR T-cell levels increased in a utomilumab dose-dependent manner up to 100 mg. Patients who received utomilumab 100 mg had persistently increased CAR T cells on Days 57-168 compared with other dose levels. Utomilumab was associated with dose-dependent increases in IL-2, IFN?, and IL-10.Utomilumab-mediated 4-1BB agonism combined with axi-cel therapy had a manageable safety profile. Dual 4-1BB and CD28 costimulation is a feasible therapeutic approach that may enhance CAR T-cell expansion in patients with LBCL.

View details for DOI 10.1158/1078-0432.CCR-23-0916

View details for PubMedID 37527011