It'S The Response That Matters: Real-World Data Of Multiple Myeloma Patients Treated Without Upfront Stem Cell Transplant

Context The treatment paradigm of newly diagnosed multiple myeloma (NDMM) has changed in the last decade. We report treatment outcomes among NDMM patients in the era of proteasome inhibitors (PI) and newer immunomodulatory drugs (IMiDs) in an Indian cohort who were not planned for upfront stem cell transplant. Objectives The primary objective was to determine the progression-free survival (PFS) of NDMM patients. Secondary objectives included objective response rates (ORR), (≥ partial response [PR]), and factors for relapse. Design Single-center ambispective study of NDMM patients diagnosed between January 2014 and December 2019 and followed until May 2021. Setting A North Indian tertiary cancer referral center. Patients Records of 650 NDMM patients were screened for the study. All received initial induction therapy followed by maintenance treatment. Two hundred forty-eight (39.2%) patients with incomplete induction therapy and significant missing data were excluded; 402 patients were included in study. Results Median age was 59.4 years (range: 23 to 84 years), and the male:female ratio was 1.9:1. Two hundred twenty-five (56%) patients had an IgG subtype, 248 (61.7%) patients had ISS stage III, 323 (80.3%) patients received triplet-based induction regimen, and 79 (19.7%) with doublets. VRd was the most common regimen, used in 123 (32.1%) patients. Following induction, 222 (52.2%) patients were treated with bortezomib, 142 (35.3%) received IMiDs, and 12% received no maintenance. ORR was 84.9% (67/79) with doublets and 95.2% (302/323) with triplets. Complete response was observed in 31.4% (103/323) patients on triplets and 29.1% (23/79) patients on doublets. After a median follow-up of 32.9 months (range: 0–102 months), median PFS did not differ by type of induction (22.8 vs 28.5 months in doublets; hazard ratio [HR] 1.06, 95% CI 0.71–1.58; p=0.8). Multivariate Cox proportion analysis suggested that response to induction ( Conclusion In NDMM patients, we suggest that depth of response, irrespective of induction and treatment with IMiDs, predicts a better PFS. However, these findings require validation by a randomized, controlled trial.