AI Proteins, a Boston-based biotech redefining how biologic therapies are created, has raised $41.5 million in Series A financing to accelerate development of medicines built entirely from first principles using artificial intelligence. The round was co-led by Mission BioCapital and Santé Ventures, with continued support from Lightchain Capital, Cobro Ventures, and other existing investors.
The company is pioneering a new therapeutic class based on AI-designed miniproteins engineered without reliance on natural templates. Its discovery platform integrates generative AI, synthetic biology, and advanced automation to deliver precise control over function, stability, and pharmacology. These compact biologics can be tailored for highly specialized mechanisms — including multispecific activity and targeted delivery — that extend beyond the limitations of traditional antibodies.
AI Proteins has already validated the scalability of its platform through partnerships and internal programs, including a collaboration with Bristol Myers Squibb valued up to $400 million. With this new capital, the company will advance its pipeline of therapeutic candidates and strengthen its technology foundation as it brings fully de novo biologic medicines closer to clinical reality.
