The Phase II KarMMA study results of the bb2121 CAR T therapy (ideacabtagene vicleucel, also called ide-cel) in patients with relapsed myeloma showed a response rate in almost 75% of patients. The results were recently published in the New England Journal of Medicine. The trial results support the FDA application currently under review, with a decision date set for March 27, 2021. 

Dr. Nikhil Munshi, MD of the Dana-Farber Cancer Institute said in a press release: 

“Despite numerous advances in the treatment of multiple myeloma, relapses are common. Patients whose disease continues to worsen after receiving standard therapy have relatively few treatment options that provide high response rates. The results of this trial represent a true turning point in the treatment of this disease. In my 30 years of treating myeloma, I have not seen any other therapy as effective in this group of patients.”

In this Phase II study, the investigators sought to confirm the efficacy and safety of ide-cel in patients with relapsed and refractory myeloma. The study included relapsed patients with at least three previous regimens including a proteasome inhibitor, an immunomodulatory agent, and an anti-CD38 antibody were enrolled. The study included 128 patients who received ide-cel. 

Study results included the following: 

• At a median follow-up of 13.3 months, 94 of 128 patients (73%) had a response, and 42 of 128 (33%) had a complete response or better
• Minimal residual disease (MRD)–negative status (<10⁻⁵ nucleated cells) was confirmed in 33 patients, representing 26% of all 128 patients who were treated and 79% of the 42 patients who had a complete response or better
• The median progression-free survival was 8.8 months (95% confidence interval, 5.6 to 11.6)
• Common toxic effects among the 128 treated patients included neutropenia in 117 patients (91%), anemia in 89 (70%), and thrombocytopenia in 81 (63%)
• Cytokine release syndrome was reported in 107 patients (84%), including 7 (5%) who had events of grade 3 or higher
• Neurotoxic effects developed in 23 patients (18%) and were of grade 3 in 4 patients (3%); no neurotoxic effects higher than grade 3 occurred
• Cellular kinetic analysis confirmed CAR+ T cells in 29 of 49 patients (59%) at 6 months and 4 of 11 patients (36%) at 12 months after infusion