Versant Ventures has unveiled its latest immunology-focused startup, Granite Bio, which emerges from stealth mode with $100 million in funding and two promising antibody drugs in its pipeline targeting inflammatory conditions.
The company, developed through Versant's Ridgeline Therapeutics discovery engine, has been operating quietly since 2021 when it secured a $30 million Series A financing led by Versant and Novartis' venture arm. Granite subsequently raised a $70 million Series B round in 2023, with participation from Forbion and Sanofi's venture fund.
Novel Approach to Inflammatory Bowel Disease
Granite's lead candidate, GRT-001, represents a potentially groundbreaking approach to treating inflammatory bowel disease (IBD). The antibody targets pro-inflammatory monocytes, white blood cells that play a crucial role in immune responses to infections and inflammation.
The drug is currently undergoing Phase 1 testing in healthy volunteers, with clinical trials in ulcerative colitis patients expected to commence later this year.
Patrick Loustau, CEO of Granite Bio, explained the scientific rationale behind their approach: "By targeting the cellular source of IBD, we believe GRT-001 has the potential to reset patients' immune systems, potentially leading to more durable and effective outcomes compared to existing therapies."
Loustau suggested that monocyte-depleting agents could impact the innate immune system in ways comparable to how B-cell targeting drugs affect the adaptive immune system, potentially opening treatment possibilities across multiple inflammatory conditions.
Expanding Beyond IBD with IL-3 Inhibition
The company's second development program, GRT-002, takes aim at a different immunological target. This antibody homes in on interleukin-3 (IL-3), a cytokine that differs from those targeted by established therapies such as Dupixent and Cosentyx.
According to Granite, IL-3 plays a significant role in both autoimmunity and type 2 inflammation, making it a promising target for conditions characterized by itch and allergies. Clinical trials for GRT-002 are expected to begin in 2026.
Versant's Growing Immunology Portfolio
Granite Bio joins Versant's expanding roster of immunology-focused biotechs. In 2024 alone, the venture firm has launched Santa Ana Therapeutics, which develops targeted immune therapies, and Borealis Biosciences, which concentrates on treatments for inflammatory kidney diseases.
This strategic focus reflects the broader industry trend of venture capitalists actively seeking novel immunology approaches to address unmet needs in inflammatory conditions.
Market Context and Potential Impact
The IBD treatment landscape has seen significant advances in recent years, yet substantial unmet needs remain. Current biologics and small molecule therapies often provide temporary relief but may lose efficacy over time or come with concerning safety profiles.
If successful, Granite's approach targeting the cellular sources of inflammation could potentially offer longer-lasting disease modification rather than just symptom management. This would represent a significant advancement for patients with ulcerative colitis and other inflammatory bowel conditions.
Similarly, the allergic disease space, while served by blockbuster therapies like Dupixent, still has room for novel mechanisms that might address patient populations who don't respond to existing treatments.
With $100 million in funding secured and two differentiated assets advancing toward clinical development, Granite Bio appears well-positioned to explore these novel immunological approaches and potentially deliver meaningful advances for patients with inflammatory and allergic conditions.
