With a massive user base of doctors, the company is now seeking formal relationships with health systems

Zachary Ziegler, Ph.D., co-founder and CTO of OpenEvidence, speaks with STAT’s Mario Aguilar at the Breakthrough Summit West on Tuesday in San Francisco.Jack Simpson for STAT

Katie covers the impact of health technology on patients, clinicians, and businesses. Her stories explore the price tag of clinical AI, digital health at the FDA, and the boom in direct-to-consumer telehealth. Confidential tips can be sent on Signal at palmer.01.

SAN FRANCISCO — OpenEvidence rode the wave of early enthusiasm for large language models by building a free chatbot for doctors. Physicians, especially trainees, have flocked to the platform to help make patient care decisions; the company claims that about 650,000 U.S. physicians use it actively.

In just four years, OpenEvidence has leveraged that popularity into a $12 billion valuation, going directly to clinicians and avoiding health tech’s traditional hospital procurement process. But the company is facing competitive pressures and questions about whether its ad-based business model can continue to propel the company forward.