- First Phase III Study Results of a CELMoD Agent Presented as a Breakthrough Abstract at the 2026 ASCO Annual Meeting
- SUCCESSOR-2 Study Data Further Support the Potential of CELMoD Therapy to Improve Clinical Outcomes in Patients with Relapsed or Refractory Multiple Myeloma
ShanghaiMay 29, 2026 /PRNewswire/ — Bristol Myers Squibb today announced positive breakthrough results from the Phase III study SUCCESSOR-2 (NCT05552976), evaluating the CELMoD (cereblon E3 ligase modulator) agent mezigdomide in combination with carfilzomib and dexamethasone (MeziKd) versus carfilzomib plus dexamethasone alone (Kd) in patients with relapsed or refractory multiple myeloma (RRMM). Results showed that MeziKd achieved a clinically meaningful and statistically significant improvement in progression-free survival (PFS), with a median PFS of 18 months versus 8.3 months, and a hazard ratio of 0.48 (p<0.0001), representing a 52% reduction in the risk of disease progression or death compared to Kd.
These data represent the first Phase III results for mezigdomide and were presented as a breakthrough oral report (Abstract #LBA7506) at the 2026 American Society of Clinical Oncology (ASCO®) Annual Meeting.
“The MeziKd combination regimen demonstrated an encouraging median progression-free survival of 18 months across various treatment settings for relapsed or refractory multiple myeloma, along with a safety profile consistent with prior findings, the convenience of oral administration, and broad applicability in diverse treatment environments,” said Paul Richardson, M.D., Clinical Research Director and Clinical Program Leader, Jerome Lipper Multiple Myeloma Center, Dana-Farber Cancer Institute, and RJ Corman Professor of Medicine, Harvard Medical School. “For patients with relapsed or refractory multiple myeloma, maintaining durable disease control becomes increasingly challenging as lines of therapy increase and drug resistance deepens. Therefore, achieving a progression-free survival of up to one and a half years holds particularly significant clinical value. These exciting results presented at ASCO further underscore the therapeutic potential of MeziKd, especially for patients who urgently need more treatment options following early and late relapses.”
The study results also showed that MeziKd achieved significant PFS improvements in second- and third-line treatments, as well as in patients with high-risk disease. The objective response rate (80.2% vs 53.4%) and rate of complete response or better (26.7% vs 8.9%) were also superior in the MeziKd arm compared to the control arm. Median overall survival has not yet been reached. The safety profile of MeziKd was consistent with the known profiles of mezigdomide and the combination regimen. In the MeziKd and Kd arms, the incidence of Grade 3–4 treatment-emergent adverse events was 83.7% and 56.5%, respectively; neutropenia occurred in 61.1% and 9.1% of patients, and infections occurred in 34.0% and 15.6% of patients.
“Multiple myeloma is a relentless disease, and patients face urgent unmet needs from the time of their first relapse,” said Cristian Massacesi, M.D., Executive Vice President, Chief Medical Officer, and Head of Research and Development, Bristol Myers Squibb. “Equally important, these data further validate the importance of our targeted protein degradation platform and cereblon as a key therapeutic target in multiple myeloma. Mezigdomide is a highly potent oral CELMoD agent, and we remain committed to advancing it as a potential new standard of care across various treatment settings for relapsed or refractory multiple myeloma.”
The results of the SUCCESSOR-2 study will be shared with health regulatory authorities. Bristol Myers Squibb extends its sincere gratitude to the patients and investigators who participated in the clinical trial.