Chai Discovery, a biotech startup backed by OpenAI, raised $130 million in a Series B funding round at a $1.3 billion valuation. The round was led by General Catalyst and Oak HC/FT, with participation from Menlo Ventures, Thrive Capital, OpenAI, Dimension, Neo, SV Angel, and new investors including Glade Brook and Emerson Collective. The financing brings the company’s total funding to more than $225 million.
Founded in 2024, Chai Discovery is part of a growing wave of biotech firms applying AI to accelerate drug development. The company builds foundation models designed to predict biochemical interactions and enable the creation of novel molecules. Menlo Ventures previously led Chai’s $70 million Series A in August, describing the company’s technology as a platform for reprogramming molecular interactions to develop new therapies.
Chai’s latest model, Chai 2, follows last year’s release of Chai 1 and focuses on de novo antibody design, which involves creating custom antibodies from scratch. The company said Chai 2 has demonstrated higher success rates than traditional approaches. CEO and co-founder Josh Meier, a former OpenAI researcher and ex-Facebook engineer, said the models are capable of designing molecules with properties required for real-world drug candidates and targeting previously unreachable biological challenges.
