CytomX Varseta-M Achieves 32% ORR, 7.1-Month PFS; Q4 Results March 16
CytomX’s EpCAM PROBODY ADC varsetatug masetecan showed 20% ORR at 8.6 mg/kg and 32% ORR at 10 mg/kg with median PFS of 6.8 and 7.1 months in advanced colorectal cancer Phase 1 expansion. The company plans mid-year FDA meetings on registrational trial design and will release Q4 results March 16.
1. Phase 1 Expansion Results
As of the January 16, 2026 data cutoff, 56 efficacy-evaluable patients in Phase 1 expansion at 7.2, 8.6 and 10 mg/kg Q3W achieved confirmed ORRs of 6%, 20% and 32% respectively, with median PFS of 5.5, 6.8 and 7.1 months and an 88% disease control rate across cohorts.
2. Safety and Tolerability
In 20 patients receiving optimized anti-diarrheal prophylaxis at 8.6 and 10 mg/kg, Grade 3 diarrhea occurred in 10% of cases and no interstitial lung disease or febrile neutropenia was reported, supporting a manageable safety profile.
3. Planned Registrational Strategy
CytomX is targeting mid-year meetings with FDA to align on a registrational trial design for late-line colorectal cancer, has initiated a Phase 1 combination study with bevacizumab, and plans a Phase 1b/2 chemotherapy combination study by the end of 2026.
4. Upcoming Q4 Earnings Release
The company will release its fourth-quarter 2025 financial results before market open on March 16, following recent revisions from Wall Street analysts.