Lancet Oncol

Background: In CARTITUDE-4, a single infusion of ciltacabtagene autoleucel (cilta-cel) significantly prolonged progression-free survival in patients with lenalidomide-refractory multiple myeloma. We report updated overall survival and longer-term efficacy and safety outcomes.

Methods: CARTITUDE-4 is an open-label, multicentre, randomised, phase 3 trial at 81 hospital sites in the USA, Europe, Asia, and Australia. Eligible patients were adults (aged >18 years) with lenalidomide-refractory multiple myeloma, with one to three previous treatment lines, including a proteasome inhibitor and an immunomodulatory drug, and an Eastern Cooperative Oncology Group performance status of 0 or 1. After the trial started, the threshold defining measurable disease was lowered to 0·5 g/dL from 1·0 g/dL serum monoclonal paraprotein on July 2, 2021, to increase trial access. Patients were randomly assigned (1:1) via a computerised algorithm and balanced with permuted blocks, with stratification by physician's choice of pomalidomide-bortezomib-dexamethasone versus daratumumab-pomalidomide-dexamethasone, International Staging System stage, and number of previous treatment lines. Patients were assigned to cilta-cel (apheresis, bridging therapy [at least one pomalidomide-bortezomib-dexamethasone or daratumumab-pomalidomide-dexamethasone cycle], lymphodepletion, then cilta-cel infusion [0·75 × 106 CAR T cells per kg]) or standard of care (pomalidomide-bortezomib-dexamethasone [21-day cycles: 4 mg/day oral pomalidomide on days 1-14; 1·3 mg/m2 subcutaneous bortezomib twice a week for 2 weeks for eight cycles, then once a week for 2 weeks per cycle; 20 mg or, if aged >75 years, 10 mg oral dexamethasone on days 1, 2, 4, 5, 8, 9, 11, and 12 for eight cycles, then days 1, 2, 8, and 9 per cycle] or daratumumab-pomalidomide-dexamethasone [28-day cycles: 1800 mg subcutaneous daratumumab weekly for 2 cycles, every 2 weeks for four cycles, then every 4 weeks; 4 mg/day oral pomalidomide on days 1-21; 40 mg/week or, if aged >75 years, 20 mg/week oral or intravenous dexamethasone]). The primary endpoint was progression-free survival, previously published. In this Article, we report a prespecified second interim analysis of overall survival and an updated analysis of progression-free survival in the intention-to-treat population. This trial was registered at ClinicalTrials.gov (NCT04181827) and is ongoing.

Findings: Patients were randomly assigned between July 10, 2020, and Nov 17, 2021, to receive cilta-cel (n=208) or standard of care (n=211). At a median follow-up of 33·6 months (IQR 20·3-35·0), median progression-free survival was not reached (95% CI 34·5 months-not evaluable) in the cilta-cel group versus 11·8 months (9·7-14·0) in the standard-of-care group (HR 0·29 [95% CI 0·22-0·39]). Median overall survival was not reached (95% CI not evaluable) with cilta-cel versus not reached (37·7 months-not evaluable) with standard of care (HR 0·55 [95% CI 0·39-0·79]; p=0·0009). 30 (14%) of 208 patients in the cilta-cel group and 77 (37%) of 208 in the standard-of-care group had maximum grade 3 treatment-emergent adverse events, most commonly anaemia (72 [35%]) in the cilta-cel group and neutropenia (59 [28%]) in the standard-of-care group. Rates of maximum grade 4 treatment-emergent adverse events were 156 (75%) with cilta-cel and 116 (56%) with standard of care, most commonly neutropenia (152 [73%] with cilta-cel and 112 [54%] with standard of care). Serious treatment-emergent adverse events occurred in 98 (47%) patients in each group. Deaths in the safety population occurred in 50 (24%) in the cilta-cel group and 82 (39%) in the standard-of-care group, including due to treatment-related adverse events in six (3%; four due to infection) in the cilta-cel group and five (2%; all due to infection) in the standard-of-care group.

Interpretation: The significantly improved overall survival and patient-reported measures in CARTITUDE-4 reinforce the use of cilta-cel in treating relapsed or refractory multiple myeloma as early as after first relapse.

Funding: Johnson & Johnson, Legend Biotech USA.