BigHat Biosciences raises $75M Series C

DFJ Growth and Premji Invest co-led the round, with Catalio Capital Management, LG Technology Ventures and Sigmas Group joining. Returning backers include Andreessen Horowitz, Amgen Ventures, Eli Lilly and Merck's venture fund. Proceeds support BHB810, a CDH17-directed antibody-drug conjugate for gastric and other gastrointestinal cancers. It entered a Phase I dose-escalation study, with the first patient dosed in September 2026. A CEACAM6 T-cell engager, BHB299, is nearing the end of preclinical development. Valuation was not disclosed in the sources reviewed. The round follows a Series B in 2022 and a $44 million Series B extension in 2025. BigHat's Milliner platform pairs machine learning with an automated, high-throughput wet lab. Model-proposed designs are made and measured, and the results feed back into training. Axios Pro noted the company is among the first AI drug developers to have a drug in clinical trials. For AI founders, the round shows where late-stage money is going in AI drug design: companies that own the loop between models and lab-generated data, and that can show a clinical asset. BigHat describes its own data generation as the base for its protein design models. Investors are paying for proprietary data and human trial results, not model architecture alone. Pharma-affiliated investors on the cap table also point to a partnership route for startups that can show those results.