Real-world efficacy and safety of the carfilzomib-pomalidomide-dexamethasone regimen in patients with relapsed/refractory multiple myeloma: A multicenter retrospective study.

Relapsed and refractory multiple myeloma (RRMM) is generally associated with a poor prognosis. This real-world study aims to evaluate the efficacy and safety of the carfilzomib-pomalidomide-dexamethasone (KPd) regimen in patients with RRMM. A multicenter, retrospective study was conducted in four centers in China. RRMM patients who received at least 1 cycle of KPd across four centers were retrospectively included and stratified by prior lines of treatment, survival outcomes and safety profile were analyzed. A total of 82 patients were enrolled. Based on the lines of treatment (LOT) at KPd initiation, patients were stratified into second-line (2L, n=39), third-line (3L, n=26), and fourth-line or beyond (4L+, n=17) groups. Among 72 response-evaluable patients, the overall response rate (ORR) was 69.4%, with ORRs of 79.4%, 73.9%, and 40.0% in the 2L, 3L, and 4L+ groups, respectively. After a median follow-up of 10.8 months, the median progression-free survival (mPFS) for the entire cohort was 22.5 months, while the median overall survival (mOS) was not reached (NR). The mPFS was NR, 22.5, and 10.1 months (P=0.178), and the mOS was NR, NR, and 11.6 months (P=0.019) for patients receiving KPd in the 2L, 3L, and 4L+ settings, respectively. Multivariable analysis identified elevated lactate dehydrogenase (LDH) level (HR=3.489, 95% CI: 1.557-7.823) and LOT ≥4 (HR=2.791, 95% CI: 1.086-7.177) as independent predictors of inferior PFS (P<0.05), while LOT ≥4 (HR=3.917, 95% CI: 1.258-12.200) was also associated with worse OS (P=0.019). Grade ≥3 adverse events (AEs) occurred in 12.8%, 50.0%, and 47.1% of patients in the 2L, 3L, and 4L+ groups, respectively. The KPd regimen demonstrated favorable clinical efficacy and manageable toxicity in RRMM, particularly in those with early-line relapse.