Granite Bio AG, a clinical-stage immunology company based in Basel, Switzerland, and San Francisco, California, emerged from stealth in April 2025 with $100 million in funding. This capital comprises a $30 million Series A led by Versant Ventures and Novartis Venture Fund, and a $70 million Series B led by Forbion and Sanofi Ventures. ​

The company is developing first-in-class antibody therapies targeting fundamental drivers of inflammation, autoimmunity, and fibrosis. Its lead candidate, GRT-001, depletes pro-inflammatory monocytes implicated in autoimmune diseases. As of Q2 2025, Phase Ia trials with healthy volunteers are being conducted, GRT-001 is expected to enter a Phase Ib trial in patients with inflammatory bowel disease later in 2025. The second candidate, GRT-002, targets interleukin-3, a cytokine involved in autoimmune and type II inflammation, with plans to initiate clinical trials in 2026. 

Both antibodies were developed in collaboration with Versant’s Ridgeline Discovery Engine and originated from the laboratory of Professor Matthias Mack at the University of Regensburg. Granite Bio is led by CEO Patrick Loustau, formerly of Amolyt Pharma, with a leadership team experienced in immunology and drug development.