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

Chai Discovery, a biotech startup backed by 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 company’s total funding now exceeds $225 million.

The company is one in a growing industry that sees AI as a faster route to drug development. In August, Menlo Ventures announced it led Chai’s $70 million Series A round. The investor described Chai as a startup that built basic models tailored to drug discovery, specifically to predict interactions between biochemical molecules so they could be reprogrammed for healing.

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

“Our latest models can design molecules that have properties we expect from real medicines and tackle challenging targets that have been out of reach,” Josh Meier, co-founder and CEO of Chai, said in a prepared statement.

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