Agenus reports 3-year survival data in colorectal cancer study

• Agenus (NASDAQ:AGEN) reported 3-year Phase 1b data for botensilimab plus balstilimab in metastatic colorectal cancer.
• The study showed 21.2-month median overall survival and a 33% 3-year overall survival rate.
• No new safety signals were observed, and 98% of immune-mediated colitis cases resolved with treatment.

Agenus (NASDAQ:AGEN) reported updated Phase 1b clinical data for its botensilimab (BOT) and balstilimab (BAL) combination in patients with refractory microsatellite-stable metastatic colorectal cancer without active liver metastases.

The fully enrolled 123-patient cohort showed a median overall survival of 21.2 months and a 33% three-year overall survival rate, based on extended follow-up data presented at the 2026 ESMO GI Congress.

Researchers reported that 17% of patients were alive and off all systemic anticancer therapy at last follow-up, suggesting durable treatment-free survival in a subset of patients.

The safety analysis showed no new safety signals, no treatment-related deaths, and a 98% resolution rate for immune-mediated diarrhea and colitis cases.

The study included heavily pretreated patients, many of whom had received multiple prior lines of therapy with limited remaining treatment options.

Agenus said the findings support continued development of the BOT+BAL combination in the ongoing Phase 3 BATTMAN trial.