OpenAI-Backed Biotech Startup Chai Discovery Raises $70 Million Led by Anthology

AI-driven biotech startup Chai Discovery has secured $70 million in series A funding, elevating its valuation to approximately $550 million.

The round was led by Menlo Ventures through its Anthology Fund—a joint effort with Anthropic—alongside new investors Yosemite, DST Global Partners, SV Angel, Avenir, DCVC, and contributions from returning backers Thrive Capital, OpenAI, Dimension, Neo, Lachy Groom, and Fred Ehrsam. 

The startup will use the funds to advance its flagship AI platform, including its latest model, Chai‑2, which delivers fully de novo antibody design with a ~20% hit rate—far above the ~0.1% success rate of traditional lab-based methods.

Mikael Dolsten, former chief scientific officer at Pfizer, who played a key role in advancing 150 molecules into clinical trials and delivering 36 approved drugs, has joined Chai’s board of directors. 

Founded in 2024 by Joshua Meier (formerly of Absci, Facebook AI, and OpenAI), Jack Dent (ex-Stripe), Matthew McPartlon, and Jacques Boitreaud, Chai’s mission is to transform biology from science into engineering, using AI to design novel therapeutic molecules from scratch. 

Chai is positioning itself against more established players like Isomorphic Labs, the drug discovery company born out of Google’s DeepMind. Led by Nobel laureate Demis Hassabis, Isomorphic secured $600 million in funding this March.

While Chai emerges as a formidable contender in the burgeoning AI-powered drug discovery space, it is yet to deliver the industry’s first AI-designed drug approval.