Equecabtagene autoleucel shows antitumour activity in heavily pretreated RRMM

The fully human-derived B-cell maturation antigen-targeting chimeric antigen receptor (CAR) T-cell therapy equecabtagene autoleucel (eque-cel) appears to induce early, deep, and lasting responses in patients with heavily pretreated relapsed or refractory multiple myeloma (RRMM), according to the results of the phase Ib/II FUMANBA-1 trial.

A total of 103 adult patients (median age 58 years, 53.4 percent male) with RRMM who received at least three prior courses of therapy were given a single infusion of eque-cel at 1.0 × 106 CAR-positive T cells/kg after the lymphodepletion. Researchers evaluated the drug’s efficacy (primary), as well as its safety, pharmacokinetics, and pharmacodynamics.

Among the 101 patients who were evaluable for efficacy, the overall response rate was 96.0 percent over a median follow-up of 13.8 months. Of note, nearly three-fourths of patients achieved a complete response or better (75 of 103, 74.3 percent). Nine of 12 patients (75 percent) who had prior CAR T-cell treatment responded to eque-cel treatment.

The median progression-free survival (PFS) was not reached, and the 12-month progression-free survival was 78.8 percent (95 percent confidence interval, 68.6–86.0). At a sensitivity threshold of 10−5, minimal residual disease negativity was reported in 96 patients (95.0 percent).

In terms of safety, adverse events were favourable. Cytokine release syndrome occurred in 96 of 103 patients (93.2 percent; grade 1 to 2 in 95 patients [92.3 percent]), while immune effector cell–associated neurotoxicity syndrome (grade 1 to 2) occurred in two patients (1.9 percent). All these events were resolved with treatment. There were 20 patients (19.4 percent) who had antidrug antibodies.

CAR-positive T cells were confirmed by cellular kinetic analysis in all patients, with the longest duration at 735 days.