Granite Bio has emerged from stealth with $100 million in funding to develop novel treatments for inflammatory and autoimmune diseases, conditions that disproportionately affect women. The clinical-stage immunology company secured a $30 million Series A led by founding investors Versant Ventures and Novartis Venture Fund, followed by a $70 million Series B led by Forbion and Sanofi Ventures.
The company’s approach targets fundamental drivers of inflammation, autoimmunity, and fibrosis—biological processes that contribute to conditions in which women represent the majority of patients. Autoimmune diseases such as rheumatoid arthritis, lupus, multiple sclerosis, and inflammatory bowel disease affect approximately 8% of the global population, with women accounting for nearly 80% of these cases.
Granite’s lead antibody, GRT-001, depletes pro-inflammatory monocytes that drive autoimmunity and inflammation. The company reports that in non-human primate studies, GRT-001 efficiently depleted these cells while sparing tissue-resident macrophages important for maintaining healthy tissue function. The antibody is currently in Phase 1a testing in healthy volunteers and is expected to enter a Phase 1b trial in patients with inflammatory bowel disease later this year.
“Granite is pioneering a new approach to tackling inflammation, autoimmunity, and fibrosis by addressing fundamental disease drivers at their source,” said Patrick Loustau, president and CEO. “With the support of an exceptional investor syndicate and a world-class team, we are advancing a pipeline of first-in-class therapies with the potential to transform patient outcomes.”
The company’s second antibody, GRT-002, blocks interleukin-3, a key player in autoimmune inflammation and type II inflammation. This approach offers potential new treatments for conditions involving itch and allergy, including atopic dermatitis—another condition with higher prevalence in women. GRT-002 is in preclinical development with clinical trials expected to begin in 2026.
Both antibodies were developed in collaboration with Versant’s Ridgeline Discovery Engine in Basel, Switzerland, and originated from the laboratories of Professor Matthias Mack at University of Regensburg.
“Despite multiple immunology-based therapeutic approaches currently commercialized, patients with inflammatory disorders continue to experience a lack of symptom control and relapse,” said Nigel Sheail, partner at Versant and Granite board member. “Granite has the potential to enable a real step change for patients with its innovative programs that target key fundamental disease pathways.”
The substantial funding reflects growing investor interest in addressing autoimmune conditions, particularly as research continues to uncover sex-based disparities in immune function. Women’s stronger immune responses, while beneficial against infections, may contribute to their increased susceptibility to autoimmune disorders. This biological difference is thought to be influenced by sex hormones, genetic factors related to the X chromosome, and microbiome variations.
Granite Bio has assembled an experienced leadership team including Patrick Loustau as president and CEO, Dominik Hartl, M.D. as CMO, Gijs van den Brink, M.D., Ph.D. as CSO, and Eliot Forster as chairperson of the board. This team brings extensive experience in immunology, drug development, and company building.
As autoimmune diseases represent a significant burden for women’s health globally, Granite Bio’s novel approaches could offer meaningful advances in treatment options for this underserved patient population.
