Xilio Therapeutics' Vilastobart Achieves 40% ORR in MSS mCRC Patients

Xilio Therapeutics reported a 40% objective response rate (ORR) in heavily pre-treated patients with microsatellite stable (MSS) metastatic colorectal cancer (mCRC) without liver metastases. The company also estimates that 55% of patients with MSS CRC have high plasma tumor mutational burden (TMB), representing a significant population with unmet need. The data was from the Phase 2 clinical trial evaluating vilastobart, a tumor-activated, Fc-enhanced anti-CTLA-4, in combination with atezolizumab.