C4 Therapeutics Advances Cemsidomide in Combination Trial for Relapsed Myeloma

Event summary

  • First patient dosed in Phase 1b trial of cemsidomide + elranatamab for relapsed/refractory multiple myeloma.
  • Trial will enroll up to 54 patients, evaluating 50 µg, 75 µg, and 100 µg doses of cemsidomide.
  • Primary endpoint: safety and tolerability; secondary endpoints include overall response rate and MRD-negative complete response.
  • Phase 1b data expected mid-2027; trial supported by Pfizer’s no-cost supply of elranatamab.
  • Part of broader strategy including the Phase 2 MOMENTUM trial for later-line myeloma treatment.

The big picture

C4 Therapeutics is expanding cemsidomide’s potential as a foundational therapy in multiple myeloma, combining it with Pfizer’s elranatamab to enhance immune responses. This Phase 1b trial is part of a broader push to integrate targeted protein degradation with immune-directed approaches, addressing the unmet need for more durable treatments in relapsed/refractory patients. The collaboration with Pfizer underscores the strategic importance of combination therapies in oncology.

What we're watching

Clinical Efficacy
Whether cemsidomide’s combination with elranatamab delivers deeper, more durable responses in earlier lines of therapy.
Regulatory Pathway
The pace at which Phase 1b data could accelerate cemsidomide’s development across multiple myeloma treatment lines.
Competitive Positioning
How C4T’s strategy of leveraging IKZF1/3 degraders differentiates it in the evolving multiple myeloma treatment landscape.