A study reported updated results from the CARTITUDE-1 trial, which previously showed that cilacabtagene autoleucel (cilta-cel) demonstrated early, deep, and durable responses in patients with relapsed/refractory multiple myeloma that had been heavily pretreated. The study was conducted by Thomas Martin, MD, and colleagues and was presented at the 2021 American Society of Hematology Annual Meeting.
The study sought to characterize cilta-cel safety, confirm the recommended phase II dose (from phase Ib), and evaluate cilta-cel efficacy (phase II). Researchers assessed 97 eligible patients with myeloma who received three or more prior therapies; whose disease was refractory to a proteasome inhibitor (PI) and an immunomodulatory drug (IMiD); and who had received a PI, IMiD, and an anti-CD38 antibody. The study population were administered a single cilta-cel infusion over 5 to 7 days following lymphodepletion.
The results show that, as of a data cut-off of February 11, 2021, the population of interest had received a median of six prior lines of therapy. The treatment has demonstrated robust efficacy, with an objective response rate (ORR) of 97.9%. The investigators observed that more than 80% of patients achieved stringent complete response (sCR), and around 95% achieved very good partial response or better. They noted that the median time to first response was 1 month (range = 0.9-10.7), suggesting rapid response. The median time to best response was 2.6 months (range = 0.9-15.2), and the median time to CR or better was also 2.6 months (range = 0.9-15.2).
Responses also appeared to be durable, with a median duration of response of 21.8 months, according to the researchers. The 18-month progression-free and overall survival rates were 66% and 80.9%, respectively.
In terms of the treatment’s safety profile, the most common grade 3/4 hematologic adverse events (AEs; occuring in ≥25% of patients) were neutropenia (94.8%), anemia (68.0%), leukopenia (60.8%), thrombocytopenia (59.8%), and lymphopenia (49.5%). There were no patient deaths related to cytopenias and no new safety signals.
The researchers concluded that, “cilta-cel demonstrated a manageable safety profile with no new safety signals observed with longer follow-up. Further investigations of cilta-cel are ongoing in earlier lines of therapy and in outpatient settings.”