Bunkerhill Health nabs $55M to scale healthcare AI agents

The real challenge in medical AI has never been about building smarter models. It has always been about getting hospitals to actually use them. Bunkerhill Health is now armed with fresh capital to solve that exact problem.

The startup has secured a $25 million Series B led by Khosla Ventures, the company exclusively told Fortune. This brings its total funding to $55 million. Returning investors include Sequoia, Felicis, Optum Ventures, and Y Combinator.

The growth numbers speak for themselves. Over the last year, the company’s revenue multiplied 20 times, and it now counts more than a dozen health systems as clients, according to founder Nishith Khandwala.

Bunkerhill’s offering is a platform called Carebricks, which allows hospitals to build and deploy AI agents tailored to their specific needs. A hospital brings a problem , long wait times, missed follow-ups, or administrative paperwork , and turns that idea into a working agent. The platform is already live at 15 health systems, including Cleveland Clinic, Mayo Clinic, and Intermountain Health. It also hosts nine FDA-cleared clinical algorithms, one that detects silent heart-valve disease and another that flags osteoporosis risk.

The origin story is deeply personal. Khandwala began this work at Stanford in 2017, but nearly abandoned it after hospitals repeatedly turned him away. Then in 2020, his father suffered a heart attack. A cardiologist later told the family that an old scan had already indicated the risk. “I think we could have caught this earlier,” Khandwala recalled the doctor saying. He co-founded Bunkerhill with David Eng, and the core mission has not changed since.

“Medicine has advanced faster than our healthcare system’s ability to operationalize it,” Khandwala said. “Why should a hospital need to work with 100 different companies to solve 100 different problems?”

The results are tangible. At the University of Texas Medical Branch, 22 agents are currently in use. In their first month, one agent that reads coronary scans flagged a patient at imminent risk. Doctors sent him to cardiology for a triple bypass, and his care team credits the agent with saving his life. Other agents have cut nephrology wait times by more than half and accelerated follow-ups on lung findings by 80%. UTMB’s AI chief Peter McCaffrey describes the platform as “a shared brain” for the health system. “We don’t need superintelligence to solve our biggest problems,” he said. “We need average intelligence.”

Still, the field carries real risks. Concerns about accuracy and patient privacy persist, and Mayo Clinic now faces a lawsuit from a former research director over its AI oversight. McCaffrey insists that the doctor-patient relationship must remain “sacrosanct.”

Investment in healthcare AI continues to surge. Bunkerhill enters a wave alongside companies like Neko Health and a steady stream of medical-AI raises. Its lead backer knows the territory well: Vinod Khosla was an early OpenAI investor and has funded health startups for decades. “The bottleneck in healthcare AI was never the technology, it was getting a health system to actually run it,” Khosla said. “Bunkerhill closed that gap.”

Sequoia’s Alfred Lin, who led the seed round in 2023, is unfazed by the growing field. “I much prefer having 1,000 flowers bloom,” he said, “and the best ones will become durable over time.”