The $15 billion ad-powered AI startup your doctor may already be using

Ars Technica News

Summary

OpenEvidence, an ad-supported AI startup valued at $15 billion, is being widely adopted by doctors for clinical decision-making, even as studies yield mixed results on its effectiveness compared to general-purpose models like Gemini and GPT, and as OpenAI and Anthropic push further into healthcare.

<p>Nearly two-thirds of US doctors are turning to an AI-powered search engine to make patient decisions, propelling a little-known tech startup to a $15 billion valuation while prompting a debate over the future of patient care.</p> <p>Miami-based OpenEvidence, founded by serial entrepreneur Daniel Nadler in 2022, said that many of America’s 1 million physicians processed more than 42 million prompts last month. Doctors are using the company’s chatbot to scour medical journals and clinical guidelines to help diagnose and treat patients.</p> <p>The ads-powered platform has grown largely by word of mouth, penetrating a sector where few tools have seen similar traction. “We’re the first viral consumer internet app in healthcare,” Nadler told the FT in an interview.</p><p><a href="https://arstechnica.com/ai/2026/10/the-15-billion-ad-powered-ai-startup-your-doctor-may-already-be-using/">Read full article</a></p> <p><a href="https://arstechnica.com/ai/2026/10/the-15-billion-ad-powered-ai-startup-your-doctor-may-already-be-using/#comments">Comments</a></p>
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# The $15 billion ad-powered AI startup your doctor may already be using Source: [https://arstechnica.com/ai/2026/10/the-15-billion-ad-powered-ai-startup-your-doctor-may-already-be-using/](https://arstechnica.com/ai/2026/10/the-15-billion-ad-powered-ai-startup-your-doctor-may-already-be-using/) “The end game is literature\-based drug discovery,” Nadler said, referencing the field of data mining scientific literature for insights\. “The economic value of that as a company is going to dwarf by orders of magnitude whatever we could have charged hospitals or advertisers\.” Alexander Tarashansky, the creator of Claude Science, an Anthropic platform that supports research scientists, has also joined the company to support its clinical work\. The company needs to see off competition from frontier AI companies such as OpenAI, which has also made a play for the space with ChatGPT for healthcare\. Anthropic has also released healthcare tools, though it recently partnered with OpenEvidence to bring the tools to 100 low\- and middle\-income countries\. “The fact that doctors are adopting and using a piece of software of their own volition means there is a degree of differentiation that OpenEvidence can really lean on,” said Nworah Ayogu, a partner at investor Thrive Capital\. But analysis of OpenEvidence’s effectiveness has led to mixed results\. One study by the Mayo Clinic, an investor in the startup, found that it “provided accurate, evidence\-based recommendations” in all five patient case studies that were sampled, although its impact on treatment decisions was more limited\. Other research, including a June paper published in Nature, found that it underperformed general\-purpose AI models such as Google’s Gemini and OpenAI’s GPT on clinical benchmarks\. Eric Oermann, a neurosurgeon at NYU Langone, said there was a lack of research into the performance of individual AI tools and scant guidance on how to implement the tools in a clinical setting\. There are also widely held concerns that more junior doctors could fall foul by relying too heavily on OpenEvidence and other systems without first mastering basic knowledge of particular conditions and their prescribed treatment options\. “It’s a fun, friendly competitive pressure to play with benchmarks… \[But\] there’s no question of what AI tool physicians trust and use,” Nadler said\. *Additional reporting by George Hammond in San Francisco\.* *[© 2026 The Financial Times Ltd](https://www.ft.com/)\.[All rights reserved](https://www.ft.com/)\. Not to be redistributed, copied, or modified in any way\.*

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