Addition of Elotuzumab to Backbone Treatment Regimens for Multiple Myeloma: An Updated Meta-Analysis of Randomized Clinical Trials.

Background: The efficacy of elotuzumab, an anti-SLAMF7 monoclonal antibody, in treating relapsed/refractory multiple myeloma (RRMM) and newly-diagnosed multiple myeloma (NDMM) has varied in randomized controlled trials (RCTs). Moreover, there is limited data on its real-world application.

Methods: We conducted a systematic review and meta-analysis of RCTs investigating the addition of elotuzumab to backbone antimyeloma regimens. The primary outcome of interest was progression-free survival (PFS). Secondary efficacy outcomes included overall survival (OS), overall response rate (ORR), and rates of very good partial response or better (VGPR). Key toxicities were also evaluated.

Results: Three RRMM trials (n = 915) and 5 NDMM trials (n = 1790) were included, with 50% of the 2705 patients receiving elotuzumab-containing triplets or quadruplets. In RRMM settings, elotuzumab use significantly improved PFS (hazard ratio [HR], 0.70; 95% confidence interval [CI], 0.60-0.82; P < .001; I² = 0%). This benefit was consistent among patients with high-risk cytogenetics (HR, 0.62; 95% CI, 0.43-0.90; P = .01; I² = 0%) and was particularly evident in those previously treated with proteasome inhibitors (PIs) or immunomodulatory drugs (IMiDs). The RRMM cohort also demonstrated better OS, ORR, and ≥VGPR rate. However, the NDMM cohort showed no significant improvements in any efficacy outcomes. Despite an increase in severe (grade ≥3) infections, elotuzumab use did not adversely affect rates of severe cytopenias, severe cardiac disorders, or second primary malignancies.

Conclusions: Our results suggest that elotuzumab-containing regimens represent valuable therapeutic options for PI/IMiD-exposed patients with RRMM. In contrast, elotuzumab's role in frontline settings remains limited.