OpenAI-backed biotech firm Chai Discovery raises $130M Series B at $1.3B valuation

Chai Discovery, a biotech startup with backing from OpenAI, announced a $130 million Series B round at a $1.3 billion valuation on Monday.

The round was led by General Catalyst and Oak HC/FT, the company said. Other participants include Menlo Ventures, OpenAI, Dimension, Thrive Capital, Neo, Yosemite venture fund, Lachy Groom, SV Angel, and new investors Glade Brook and Emerson Collective. The firm’s total funding now stands at over $225 million.

The company is one in a growing industry that sees AI as a faster route toward drug development. In August, Menlo Ventures announced it was leading Chai’s $70 million Series A round. The investor described Chai as a startup that was building foundation models tuned for drug discovery, specifically to predict interactions between biochemical molecules so they could be reprogramed for cures.

Chai says that its ambition is to “build the ‘computer-aided design suite’ for molecules.” Last year, the startup announced the Chai 1 AI model and is now offering Chai 2, it’s latest model. The company says Chai 2 is achieving significant improvements in success rates over other methods for de novo antibody design, meaning building custom antibodies from scratch, not modifying existing ones.

“Our latest models can design molecules that have properties we’d want from actual drugs, and tackle challenging targets that have been out of reach,” Josh Meier, Chai’s co-founder and CEO said in a prepared statement.

Previously, Meier, whose background is in machine learning, worked in research and engineering at Facebook and, prior to that, worked for OpenAI, according to his LinkedIn. Chai Discovery was founded in 2024, the profile notes.