Allogene Modifies Lymphoma Trial After Patient Death
Allogene Therapeutics has announced a major change to its ALPHA3 clinical trial for large B-cell lymphoma (LBCL), choosing to use standard chemotherapy for lymphodepletion following the death of a patient attributed to its investigational ALLO-647, an anti-CD52 monoclonal antibody. Lymphodepletion is described as the process by which a patient receives chemotherapy to temporarily reduce the number of lymphocytes in their body before undergoing CAR T-cell therapy treatment.
The company says it will now proceed with the trial using only fludarabine and cyclophosphamide (FC) — a commonly used conditioning regimen — ahead of its off-the-shelf CAR T therapy, cemacabtagene ansegedleucel (cema-cel). The change follows recommendations from the study’s data and safety monitoring board, steering committee, and a consultation with FDA, it says.
Enrollment has been halted in the trial arm testing the combination of FC and ALLO-647. Allogene says the decision was made before a planned futility analysis, following a fatal adverse event in the ALLO-647 group. The patient died from hepatic failure on Day 54 after receiving cema-cel, it says, adding that the death was believed to be the result of disseminated adenovirus infection due to immune suppression, and was not linked to cema-cel itself.
According to the company, severe viral infections have been rare in its trials but, when they have occurred, they’ve typically been associated with immune suppression caused in part by ALLO-647. There have been no recorded cases of adenoviral infection or liver failure in patients treated with the standard FC regimen alone.
The revised ALPHA3 trial now moves forward as a randomized study comparing cema-cel following FC lymphodepletion versus observation — currently the standard of care — in patients receiving first-line consolidation therapy for LBCL. The structure and statistical design of the trial remain unchanged, with a futility analysis expected in the first half of 2026.