Solstice Oncology

Solstice Oncology is a clinical-stage immuno-oncology company built around the neoadjuvant treatment setting, the point in a patient's disease course where the company believes the opportunity to improve cure rates and long-term survival is greatest.

Founded in February 2026, Solstice is led by a team with decades of experience building and advancing successful immunotherapy drugs in oncology.

The company is advancing porustobart, a second-generation Fc-enhanced CTLA-4 antibody, across two clinical indications: a Phase 2 study in combination with pembrolizumab in the neoadjuvant setting for clinical stage II-III MSS colon cancer, and a second, undisclosed clinical indication. Solstice's initial investors include Forbion, RA Capital, and Canaan Partners.