OpenEvidence, the clinical AI search engine used by a large share of American doctors, has raised $250 million at a $15 billion valuation — and is quietly expanding from answering physicians' questions into developing cancer drugs. The round lifts the company's value 25% from the $12 billion it commanded in January and confirms healthcare as one of the hottest corners of the AI economy.
The raise was first reported by Business Insider on September 24 and followed by Axios and others. Reports say the money came from Andreessen Horowitz and undisclosed hospital systems, while Dealroom lists a16z and Byers Capital as leads. OpenEvidence itself disclosed the round only in a single sentence inside a partnership announcement.
A Steep Valuation Curve
OpenEvidence's rise has been among the fastest in AI. According to published reporting, the company's funding history runs:
- February 2025 — about $75 million Series A at a $1 billion valuation
- July 2025 — $210 million Series B at $3.5 billion
- October 2025 — $200 million Series C at $6 billion
- January 2026 — $250 million led by Thrive Capital and DST Global at $12 billion
- September 2026 — $250 million at $15 billion
The company has raised more than $1 billion over the past year from backers including Thrive, DST, GV, Kleiner Perkins, Sequoia Capital and Nvidia. It is not the top price it chased, though: The Information had reported the company explored raising at a $20 billion valuation before settling at $15 billion.
From Search Engine to Drug Developer
The bigger surprise is strategic. CEO Daniel Nadler told Forbes that OpenEvidence plans to develop cancer drugs, with a focus on rare cancers. He said the first candidate should enter clinical trials before the end of the year, with three to five more planned for next year.
That is a significant leap. OpenEvidence built its business as an evidence-retrieval tool that helps clinicians find and summarise medical literature at the point of care. Moving into therapeutics puts it alongside a growing group of AI-first drug developers — and exposes it to the long timelines and high failure rates of clinical research.
The Memorial Sloan Kettering Deal
The round surfaced alongside a partnership with Memorial Sloan Kettering Cancer Center (MSK). MSK is integrating OpenEvidence into its Epic electronic health record workflows, where around 70% of its faculty already use the tool. In exchange, OpenEvidence will make MSK's OncoKB precision-oncology knowledge base available to clinicians beyond MSK.
The deal gives OpenEvidence access to one of the world's most respected cancer knowledge sources — useful both for its search product and, potentially, for its new drug ambitions.
Why It Matters
OpenEvidence shows that vertical AI — tools built deeply for one profession — can command valuations once reserved for general-purpose platforms. Business Insider reported that roughly 40% of US physicians use the product, and the company reportedly passed $100 million in annualised revenue in January. That combination of distribution and trust among doctors is hard for horizontal chatbots to replicate.
The competitive pressure is real, however. OpenAI and Anthropic are pushing further into healthcare, and established players such as Doximity are growing their own AI search and scribe products; Doximity reported AI search queries up 25% quarter over quarter on its latest earnings call. Investors appear to be betting that deep clinical integration and proprietary data partnerships like the MSK deal will protect specialised players.
The pivot into drug development also reflects a broader pattern in the AI economy: companies with strong data positions are trying to capture more of the value chain rather than remaining software vendors. The same week, AI-driven biotech Enveda raised $311 million to push natural-compound drug candidates into trials, underscoring how much capital is flowing into AI-enabled drug discovery.
What to Watch
Key milestones include whether the first OpenEvidence drug candidate enters trials by year-end as promised, how many more health systems follow MSK into deep integration, and whether reports that the company is weighing strategic options, including a possible sale, develop further. For now, the $15 billion price tag signals that investors see clinical AI as one of the most defensible businesses in the sector.
