Bristol Myers Squibb’s Mezigdomide Delivers Positive Phase 3 Results, Potentially Opening the Door for More CELMoDs in Myeloma Treatment

March 9, 2026—According to a press release today from Bristol-Myers Squibb,"Positive interim Phase 3 results from the SUCCESSOR-2 study (NCT05552976). In the trial, oral mezigdomide in combination with carfilzomib and dexamethasone (MeziKd) demonstrated statistically significant and clinically meaningful improvement in progression-free survival (PFS) versus carfilzomib and dexamethasone alone (Kd) in patients with relapsed or refractory multiple myeloma (RRMM). Safety findings were consistent with the known profile of mezigdomide and the combination regimen. Patients will continue to be followed for survival and safety."

The SUCCESSOR-2 (NCT05552976) trial is a seamless Phase 2/3, multicenter, randomized, open-label study evaluating the oral CELMoD agent mezigdomide in combination with carfilzomib and dexamethasone (MeziKd) for patients with relapsed or refractory multiple myeloma (RRMM). The study compares this three-drug regimen with the standard combination of carfilzomib and dexamethasone (Kd).

The primary endpoint of the Phase 3 portion is progression-free survival (PFS). Key secondary endpoints include overall survival (OS), overall response rate (ORR), duration of response (DoR), time to progression (TTP), time to next treatment (TTNT), minimal residual disease (MRD) negativity, and health-related quality of life (HR-QoL).

These positive results of CELMoD mezigdomide for RRMM may signal the potential use of more of this class of drug in the treatment of multiple myeloma. Read the full press release from the button below.