Dr. Shah on Zamto-cel in R/R DLBCL

Nirav N. Shah, MD, associate professor, Medical College of Wisconsin, discusses findings from a preplanned interim futility analysis of the single-arm phase 2 DALY II USA trial (NCT04792489) in patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL).

The DALY II USA trial is investigating the efficacy and safety of freshly administered zamtocabtagene autoleucel (zamto-cel), a CD20/CD19-directed CAR T-cell therapy, in patients with DLBCL who had relapsed on or were refractory to at least 2 prior lines of therapy. The primary end point of this trial was overall response rate (ORR) at day 28. A total of 28 patients have enrolled to the trial, 22 of whom were included in the efficacy-evaluable population. Of the 6 remaining patients who were not included in the efficacy analysis, 1 received frozen zamto-cel, and 5 received CAR T-cell products that did not meet the protocol criteria.

At this interim analysis, the investigators observed similar outcomes between the evaluable population and the all treated population, with best ORRs of 82% with a 46% complete response (CR) rate and 79% with a 50% CR rate, respectively, Shah says. Additionally, the 28-day ORR was 78% in the evaluable population. In the evaluable population, the CR and partial response (PR) rates were 32% and 46% at day 28. When duration of response in the all treated population was assessed by an independent review committee, 4 patients with an initial PR had converted to a CR, and 2 patients with stable disease had converted to a PR.

The 6-month progression-free survival rates were 61% in all treated patients and 64% in the evaluable population, Shah explains. At a median follow-up of 10.3 months, the median overall survival was not reached. These findings are promising but limited, and longer follow-up is necessary to determine the durability of these responses, Shah concludes. The DALY II USA trial will continue to accrue patients.