Chai Discovery secured $70 million in Series A funding to advance its artificial intelligence platform that accelerates pharmaceutical development through computational molecular design. The biotechnology startup, which raised $30 million in seed funding last year, attracted backing from Menlo Ventures‘ Anthology Fund in partnership with Anthropic.
The funding round included new investors Yosemite, DST Global Partners, SV Angel, Avenir, and DCVC, alongside existing backers Thrive Capital, OpenAI, Dimension, Neo, Lachy Groom, and Fred Ehrsam.
AI Models Transform Antibody Discovery
The company’s breakthrough centers on Chai-2, its latest computational model that generates custom antibodies with unprecedented efficiency. Traditional laboratory screening methods require testing millions or billions of antibodies to identify viable candidates. Chai-2 achieves a 20% hit rate in antibody design, compared to the previous computational benchmark of 0.1%.
“Before Chai-2, the process was not unlike searching a giant bunch of keys for the right fit for a lock—but there are millions of keys. Now, it’s like having a master locksmith design exactly the right shape key, based only on your description of the lock” ~ Matthew McPartlon, co-founder.
The system requires only target antigen and epitope information to generate entirely new antibodies capable of precise binding. This approach enables scientists to design treatments for viruses, cancer cells, and other disease-causing proteins without existing antibody templates.
Experienced Leadership Drives Scientific Vision
Chai Discovery was co-founded in 2024 by Joshua Meier, formerly of AI drug discovery firm Absci, Facebook AI, and OpenAI; Jack Dent from Stripe; and AI researchers Matthew McPartlon and Jacques Boitreaud. Their combined expertise spans machine learning, structural biology, and large-scale product development.
Mikael Dolsten, former Chief Scientific Officer at Pfizer, recently joined the company’s board of directors. During his Pfizer tenure, Dolsten oversaw 150 molecules advancing to clinical trials and 36 medicine approvals “I’m proud to join Chai Discovery and redefine biology from science into engineering” Dolsten said.
Rapid Development Timeline Proves Technology
The company’s technology has already demonstrated real-world impact. McPartlon cited an example where a company spent over three years and $5 million on a particular problem. Using Chai-2, his team identified an experimentally validated solution within two weeks.
Chai Discovery previously released Chai-1, an open-source foundation model for molecular structure prediction that established leadership in its category. The progression from Chai-1 to Chai-2 represents significant advancement in computational drug discovery capabilities.
Strategic Focus on Platform Expansion
The Series A funding will support expanding platform capabilities to tackle previously inaccessible biological targets. The company plans to onboard select partners for collaborative research programs, building broader adoption in the biopharmaceutical sector.
“Progress towards game-changing drugs and treatments is far too slow, stymied by costly trial-and-error experiments. Chai Discovery exists to push the boundaries of what’s possible in this field, applying frontier AI to transform biology from science to engineering” ~ Joshua Meier, CEO and co-founder.
Greg Yap, Partner at Menlo Ventures, noted strong industry interest: “Chai is an exceptional technical team building foundation models for biology to transform drug discovery. We have seen a meaningful fraction of the biotech industry already apply for Chai-2 access“