In a previously reported 1-year update on the trial, 42% of patients had ongoing responses, Dr. Neelapu said. In the present update, with a median follow-up of 27.1 months, ongoing responses were seen in 39%, most of whom (37%) were in complete response, according to the data presented.
Thirty-three patients in the phase 2 portion of ZUMA-1 were known to have double-expressor or high-grade B-cell lymphoma, according to the investigator. In this high-risk subset, 48% were in ongoing complete response at the 2-year follow-up.
Progression-free survival in ZUMA-1 plateaued at the 6 month-follow-up, according to Dr. Neelapu, who said that plateau has been largely maintained, with just 10 patients progressing since then. Median progression-free survival is 5.9 months and median overall survival has not been reached, with a 24-month overall survival of 51%.
Late-onset serious adverse events mainly consisted of manageable infections, none of which were considered related to axi-cel treatment, according to Dr. Neelapu.
The proportion of ongoing responders with detectable CAR T-cells has decreased over time, from 95% at 3 months to 66% at 24 months, Dr. Neelapu reported. Meanwhile, the proportion of ongoing responders with detectable B cells after axi-cel treatment has gone from 17% to 75%.
More details on the 2-year follow-up data from ZUMA-1 were reported recently in the Lancet Oncology (2019 Jan;20[1]:31-42).
Funding for ZUMA-1 came from Kite and the Leukemia & Lymphoma Society. Dr. Neelapu reported disclosures related to Kite, Celgene, Cellectis, Merck, Poseida, Acerta, Karus, Bristol-Myers Squibb, Novartis, and Unum Therapeutics.
The meeting was held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research. At its meeting, the American Society for Blood and Marrow Transplantation announced a new name for the society: American Society for Transplantation and Cellular Therapy (ASTCT).
SOURCE: Neelapu SS et al. TCT 2019, Abstract 82.