C4 Therapeutics (CCCC) Status Update summary

Strategic development and market opportunity

• Cemsidomide is prioritized as a class-leading IKZF1/3 degrader, targeting high-value labels in multiple myeloma with a differentiated, efficient clinical plan.

• Projected $2.5–$4 billion peak revenue opportunity in relapsed/refractory multiple myeloma, aiming for significant market share in 2L+ and 4L+ settings.

• The RRMM market is projected to reach $46B by 2030, with cemsidomide leveraging combinations with BCMA BiTE and dexamethasone.

• Expanded pipeline beyond oncology and leveraging collaborations for financial milestones and capital formation.

• Cemsidomide’s differentiated safety and efficacy profile supports use across multiple lines of therapy, including heavily pre-treated populations.

Clinical trial design, results, and patient population

• Phase I enrolled heavily pretreated, relapsed/refractory multiple myeloma patients (median 7 prior therapies, 75% with prior BCMA therapy).

• Achieved 40% ORR at 75 mcg and 50% ORR at 100 mcg, with median DOR 9.3 months across all doses and not reached at highest doses.

• 67% of efficacy evaluable patients at the two highest dose levels remain on treatment, indicating durable benefit.

• Dose escalation completed up to 100 mcg, with 14 days on/14 days off regimen optimizing efficacy and neutrophil recovery.

• Safety and efficacy data support late-line development and combination strategies.

Safety and tolerability profile

• Cemsidomide plus dexamethasone showed a differentiated safety profile with manageable neutropenia and minimal dose reductions (6%).

• No discontinuations related to cemsidomide; grade 3 neutropenia in 24% and grade 4 in 33%, with low rates of febrile neutropenia and limited G-CSF use.

• Safety profile compares favorably to other IKZF1/3 degraders, with fewer treatment-disruptive adverse events.

• 32% of patients remained on treatment after eight cycles, indicating sustained benefit.

• Most myelosuppressive events occurred in early cycles.