Bristol Myers’s Mezigdomide Regimen Extends PFS to 18 Months with 80% ORR
BMY•Bristol Myers Squibb’s investigational mezigdomide regimen extended median PFS to 18.0 months versus 8.3 months and achieved an 80.2% overall response rate in R/R multiple myeloma Phase III SUCCESSOR-2 trial. Higher Grade 3/4 toxicities at 83.7% versus 56.5% may temper commercial uptake and limit use to post-CD38, post-lenalidomide patients.
1. Phase III SUCCESSOR-2 Trial Results
Bristol Myers Squibb presented updated data from the global, multicenter Phase III SUCCESSOR-2 trial comparing mezigdomide plus carfilzomib and dexamethasone (MeziKd) against carfilzomib and dexamethasone (Kd) alone in relapsed/refractory multiple myeloma patients pretreated with lenalidomide and anti-CD38 therapy. MeziKd extended median progression-free survival to 18.0 months versus 8.3 months (52% risk reduction) and improved the overall response rate to 80.2% versus 53.4%, with complete response or better in 26.7% versus 8.9%; overall survival remains immature but favors MeziKd.
2. Commercial and Competitive Outlook
Any-grade treatment-emergent adverse events occurred in 99.3% of MeziKd patients versus 95.7% with Kd alone, while Grade 3/4 events rose to 83.7% versus 56.5%, driven by neutropenia and infections. These safety findings may influence prescriber adoption, positioning MeziKd as a non-cellular option for post-CD38, post-lenalidomide patients outside specialized centers, while competition from CAR-T and bispecific therapies intensifies as the multiple myeloma market approaches $29 billion by 2032.
