The FDA has placed a clinical hold on the phase 1 PLAT-08 trial, which is evaluating SC-DARIC33 as a treatment for pediatric patients and young adults with relapsed/refractory acute myeloid leukemia (AML). The hold was initiated due to a grade 5 serious adverse effect (SAE) that occurred during the study. The developers of SC-DARIC33 are working with the FDA to investigate the cause of the toxicity and make protocol changes to continue the trial.
In a presentation at the 2023 American Society of Gene & Cell Therapy Annual Meeting, investigators shared data on SC-DARIC33 from the PLAT-08 study. One patient showed expansion of SC-DARIC33 cells in the skin, leading to the destruction of leukemic cells. Another patient showed SC-DARIC33 cell expansion in the blood, resulting in a reduction in leukemic burden. These findings suggest the potential of SC-DARIC33 as a T-cell therapy approach for AML.
The PLAT-08 trial is an open-label, non-randomized phase 1 study that aims to assess the safety and manufacturing success of SC-DARIC33. The primary endpoint is the occurrence of adverse events, and the secondary endpoint is AML response in patients with CD33-positive leukemia. Patients aged 30 or younger with relapsed/refractory CD33-positive leukemia were eligible for enrollment in the trial if they met certain criteria.