Compass Therapeutics rises after pipeline updates

Shares of Compass Therapeutics (NASDAQ:CMPX) added ~21% on Monday after the cancer drug developer, with its Q2 2025 results, announced a lower-than-expected number of mortalities in a Phase 2/3 trial for its lead asset tovecimig in biliary tract cancer.

Citing topline data from its COMPANION-002, the Boston-based biotech announced in April that the bispecific antibody reached the trial’s main goal related to overall response rate. At the time, the company planned to analyze the trial's secondary endpoints, including progression-free survival, in Q4 2025.

However, given the low number of deaths observed to date, Compass (NASDAQ:CMPX) has now pushed back that timeline with plans to do the analysis in Q1 2026.

“Because the analysis of the secondary endpoints of progression-free survival and overall survival is triggered by total deaths in the study (80% pooled mortality), we are updating our guidance on the secondary endpoint analyses to Q1 2026,” CEO Thomas Schuetz remarked.

Additionally, the company disclosed two deep and confirmed partial responses in a Phase 1 dose-escalation study designed to test its solid tumor candidate CTX-8371 in a post-checkpoint inhibitor setting.

Citing data from the study’s first four initial cohorts, CMPX said that a patient with non-small cell lung cancer achieved a complete resolution and another with triple negative breast cancer experienced over 90% reduction in target lesions.

Compass (NASDAQ:CMPX) expects to begin cohort expansions for NSCLC, TNBC, and other cancer patients in Q4 2025 with plans to release their data next year.