Efficacy and tolerability of elotuzumab-based three-drug regimens for high-risk multiple myeloma: A meta-analysis.

Abstract

e20550 Background: Efficacy of elotuzumab (E) based regimens in high risk multiple myeloma (MM) (i.e, ISS stage II/III and t(4;14) or (del17p) has not been thoroughly investigated. The aim of this study was to assess the efficacy of E based 3-drug regimens compared to non-E based regimens in high risk MM. Methods: A systematic review of literature was done to identify randomized controlled trials (RCTs) which reported overall response rates (ORR), progression free survival (PFS) and overall survival (OS) of MM patients (pts) with E based 3-drug regimens. Odds ratios (OR) of ORR were computed and hazard ratios (HR) of PFS and OS (along with 95% confidence intervals; CI) were extracted to compute a pooled HR using RevMan v.5.3 to report the efficacy of E based 3-drug regimens. A random effects model was employed only when there was significant heterogeneity among studies ( > 40%, as assessed by I-squared). Results: After screening 604 studies, 04 RCTs were included (n = 986 patients). E was evaluated with lenalidomide (L), pomalidomide (P), bortezomib (B) and dexamethasone (d). ELd regimen was studied in 359, EPd in 60 and EBd in 77 pts. Total 496 pts were evaluated with E. Pooled analysis of E based 3-drug regimens showed improved PFS (HR 0.69, 95% CI 0.59-0.81; p < 0.00001, I2 = 0%) and ORR (OR 1.92, 95% CI 1.33-2.78; p = 0.0005; I2 = 25%) as compared to non-E 2-drug regimens. Relapsed/refractory MM pts (n = 456) also showed improved ORR in E vs non-E groups (OR 1.88, 95% CI 1.19-2.97; p = 0.007; I2 = 47%). Sub-group analysis showed 30% reduction in progression in high risk MM pts (HR 0.70, 95% CI 0.53-0.94; p = 0.02; I2 = 0%) and 31% in standard risk pts (HR 0.69, 95% CI 0.53-0.88; p = 0.003, I2 = 0%). OS showed 25% reduction in risk of death with E based regimens (HR 0.75, 95% CI 0.62-0.91; p = 0.004, I2 = 0%). E proved to be clinically safe across all patients (OR 1.10, 95% CI 0.78-1.57; p = 0.58; I2 = 71%). Conclusions: Elotuzumab based 3-drug regimens appear to abrogate high risk features in MM compared to 2 drug regimens.