Pathos AI raises $237m Series E led by Bristol Myers Squibb at about $3bn valuation

Pathos AI, which uses AI to pick and develop clinical drug candidates, said on 23 October 2026 that it had raised $237 million in a Series E round led by Bristol Myers Squibb, valuing the company at approximately $3 billion ¹². Existing investors also took part ¹.

On the same day Pathos signed a two-part neuroscience arrangement ¹. BMS will work with Pathos and Tempus AI to look for new drug candidates for neurological conditions, starting with Alzheimer's disease ¹². Separately, Pathos will pay Tempus $55 million under a five-year contract to build a dataset drawn from hundreds of thousands of patients with neurological conditions, intended to guide adaptive clinical trials ¹.

The platform and the pipeline

Pathos runs a proprietary model called Foundry, which operates thousands of AI agents that estimate the probability of success of its clinical assets ². The agents analyse clinical data, genomics, biological specimen data and competing programmes, and the output steers which drugs Pathos pursues, which populations it tests them in and how it designs its trials ². Chief executive Iker Huerga said the company is "building a platform to systematically improve the probability of success in drug development" ¹.

The pipeline so far is in oncology and has been assembled largely by in-licensing ¹. It includes a Phase 3 TROP2/HER3 bispecific antibody-drug conjugate, JSKN-106, licensed from Alphamab Oncology, which the company names as a priority for the new money ¹. Other priorities are AZD4241, a PROTAC partnered with AstraZeneca, and DO-2, a MET kinase inhibitor that came with a majority stake in Belgium's DeuterOncology ¹. Pathos also holds a CBP/p300 inhibitor licensed from Novo for prostate cancer and multiple myeloma ¹. Part of the Series E will go towards scaling Foundry ¹.

What it means for the market

The round shows a large pharma company taking the lead position in equity financing for an AI-first developer while also signing it as a research partner ¹². For BMS the structure combines an ownership stake with access to Pathos's platform and to the Tempus neurological data in Alzheimer's ¹². For Tempus the contract is a $55 million, five-year sale of a data asset to a drug developer ¹.

The valuation reflects steady growth in Pathos's funding. The Series E follows a $365 million Series D in May 2025 and a $62 million Series C in October 2024 ¹. The move into neurology widens Pathos's scope beyond oncology, where its programmes have been concentrated until now ².

The sources give no financial terms for the BMS collaboration and no list of investors beyond BMS ¹². They also give no clinical evidence that Foundry's estimates have improved trial outcomes, so the case for the platform still rests on the company's own description ¹². Neither source sets out a timeline for the first candidates from the Alzheimer's work ¹².