Comparison of Standard of Care with or Without a PD-1/PD-L-1 Inhibitor for the Treatment of Multiple Myeloma: A Systematic Review and Meta-Analysis of Phase II and III Randomized Controlled Trials.

backgroundDespite recent advances in the treatment of multiple myeloma (MM), the disease remains incurable. Agents targeting the programmed death-1 (PD-1) axis have become key treatments for many cancers; however, monotherapies with PD-1/PD-L-1 inhibitors (PD-1i) have shown a limited efficacy in MM patients. We conducted a meta-analysis to evaluate the safety and efficacy of PD-1i in combination with standard of care (SOC) therapies for MM.

methodsA systematic search identified phase II and III randomized clinical trials involving MM patients treated with PD-1i, using terms such as "Relapsed Multiple Myeloma" and "PD-1 inhibitors." The search included trials published in English after 2016 using the PubMed, CINAHL, and Cochrane databases. Data were analyzed using RStudio v4.4.2, with survival data assessed using Kaplan-Meier methods and Cox proportional hazards analysis.

resultsOur search yielded 19 total trials, of which 5 (representing 889 unique patients) met the criteria for inclusion. A total of 488 patients received PD-1i + SOC, and 401 received SOC alone. The median progression-free survival (PFS) was 6.26 months for the PD-1i + SOC group and 7.34 months for the SOC alone group (HR, 1.2; 95% CI: 0.95-1.41;

conclusionThis analysis highlights the limited efficacy and increased toxicity of adding PD-1i to SOC in MM patients. Further research is needed to explore whether targeting the PD-1/PD-L1 axis in combination with novel therapies can safely enhance the therapeutic efficacy in MM patients.