Phase I Trial Results With Immunotherapy bb21217 for Resistant Multiple Myeloma
Posted: Wednesday, February 12, 2020
According to findings presented at the 2019 American Society of Hematology (ASH) Annual Meeting & Exposition (Abstract 927) of the CRB-402 phase I trial, and published in the journal Blood, the chimeric antigen receptor (CAR) T-cell therapy bb21217 demonstrated “encouraging” therapeutic responses for patients with relapsed or refractory multiple myeloma. The adverse events observed by Jesus G. Berdeja, MD, of the Sarah Cannon Center for Blood Cancers, Nashville, and colleagues appeared to be consistent with toxicities of other CAR T-cell therapies.
“Emerging data demonstrate long-term persistence of CAR T cells in long-term responders,” the authors concluded.
In this ongoing, multicenter trial, the investigators enrolled patients with relapsed or refractory multiple myeloma who had received at least three prior regimens. As of April 2019, 22 patients had been treated with bb21217—12 at a dose level of 150 x 106 CAR T cells, 6 at a dose level of 300 x 106 CAR T cells, and 4 at a dose level of 450 x 106 CAR T cells. The median prior lines of therapy were 7 for all patients, and 11 exhibited a high tumor burden.
After a median follow-up to bb21217 infusion of 23 weeks, 13 patients had developed cytokine-release syndrome and responded to supportive care, tocilizumab, and/or corticosteroids, and 5 developed neurotoxicity. The investigators reported that 18 patients were evaluated for response within less than 2 months of follow-up or progressive disease within 2 months; 15 patients exhibited clinical response (with 6 subsequently experiencing disease progression), and 9 patients remained in response.
The investigators obtained minimal residual disease–negative results at 10-5 nucleated cells or better in 10 patients at 1 month. Of the eight patients evaluable at 6 months, and the two patients evaluable at 12 months, six and two patients, respectively, had detectable CAR T cells in their blood.
Disclosure: For full disclosures of the study authors, visit ashpublications.org.