Chai Discovery, a biotech startup backed by OpenAI, has raised $70 million in a Series A funding round led by Menlo Ventures and its Anthology Fund in partnership with Anthropic. The company, founded in 2024 by Joshua Meier, Jack Dent, Matthew McPartlon, and Jacques Boitreaud, focuses on AI-driven molecular design and drug discovery. Its latest AI model, Chai-2, has demonstrated a breakthrough in antibody design, achieving a hit rate of approximately 15-20%, a substantial improvement compared to previous AI methods with a 0.1% hit rate. This model reportedly achieves a 1-in-6 binding success rate, compared to the traditional 1-in-1,000 rate, signaling a leap forward in generative AI for drug pipelines. Following this progress, Chai Discovery appointed a former Pfizer Chief Scientific Officer to its board. The funding round values the company at around $550 million and aims to support the development of new AI models to accelerate drug discovery. This development highlights ongoing advancements in AI applications within biotechnology, with other startups like Tahoe Therapeutics also raising funds to build AI models of living cells.