C4 Therapeutics' Cemsidomide Shows 53% Response Rate in Relapsed Myeloma Trial
Event summary
- C4 Therapeutics presented Phase 1 data for cemsidomide at EHA 2026, showing a 53% overall response rate in heavily pretreated relapsed/refractory multiple myeloma patients at the 100 µg dose.
- The trial included 73 patients with a median of seven prior lines of therapy, 75% of whom had received prior BCMA or CAR-T therapy.
- Cemsidomide demonstrated deepening responses over time, with some patients achieving minimal residual disease (MRD) negativity.
- The drug was well tolerated, with no discontinuations related to safety and minimal dose reductions.
The big picture
C4 Therapeutics' Phase 1 data for cemsidomide underscores the growing importance of targeted protein degradation in treating relapsed/refractory multiple myeloma. The results position cemsidomide as a potential best-in-class therapy, addressing a critical unmet need in a disease characterized by high recurrence rates. The company's focus on combination therapies could further differentiate cemsidomide in a competitive oncology landscape.
What we're watching
- Clinical Development
- Whether cemsidomide can maintain its response rates in larger, more diverse patient populations as it advances to Phase 2 trials.
- Combination Therapies
- The potential of cemsidomide in combination with other approved therapies, particularly immune-based treatments like elranatamab.
- Market Positioning
- How C4 Therapeutics positions cemsidomide against existing IKZF1/3 degraders in the relapsed/refractory multiple myeloma space.