Bitterroot Bio emerged last week, announcing a massive $145M Series A round and an equally massive mission to “rewrite the practice of cardiology” through cardio-immunology therapeutics.
Founded in 2021 and operating in stealth before now, Bitterroot Bio is taking a contrarian approach to CVD risk reduction, targeting immune response and inflammation pathways that they believe are the actual root causes of cardiovascular diseases (versus cholesterol, hypertension, etc).
Bitterroot placed more emphasis on its founders than you usually see in company launch announcements, and for good reason…
- Its Stanford-based founders were the first to discover that tumors use the CD47 protein to grow undetected by sending a misleading “don’t eat me” signal to immune cells.
- Their CD47 research led to the formation of their aptly named immuno-oncology biotech Forty Seven, which was acquired by Gilead in 2020 for nearly $5B.
- They later found that CD47 in blood vessels leads to “don’t eat me” signals that cause plaque buildup, and higher CD47 levels are associated with greater risks of stroke and heart attacks.
- While researching Forty Seven’s oncology products, they found that CD47 cancer therapy has unexpected CVD benefits.
Based on this evidence, the founders theorized that blocking CD47 might help fight cardiovascular disease, leading to their formation of Bitterroot Bio.
The company’s lead product, BRB-002, is a protein biologic that targets the CD47/SIRPα pathway to address the underlying causes of atherosclerosis and vascular inflammation, and is currently on pace for clinical trials within the next year.
Bitterroot Bio will use its new funding – reportedly the largest-ever for a preclinical CVD biotech startup – to bring BRB-002 through its Phase 1 and Phase 2a trials, evaluate BRB-002’s potential for other cardiovascular diseases, and explore complementary acquisitions.
The Takeaway
Bitterroot emerges as one of cardiology’s most novel startups, as you’d be hard pressed to find other cardio-immunology efforts in the Cardiac Wire archives, and +$100M Series A rounds for CVD treatment startups are equally rare.
That unique starting point will create many hurdles on Bitterroot’s path towards developing the first cardio-immunology treatments, but it would also mean that the company could have a uniquely large impact on cardiovascular disease care if things go right.
