ChainThink report, August 19: Anthropic enabled Claude to independently complete a round of protein design experimentation.

Claude Opus 4.8 and Mythos Preview designed small proteins capable of binding to 15 target proteins, successfully achieving binding in 14 cases.

In the experiment, researchers provided Claude with access to protein design and structure prediction tools, allowing it to autonomously research, select design sites, invoke tools, and iteratively screen and refine proposals—humans did not participate in specific design decisions.

Adaptyv Bio and Twist Bioscience subsequently synthesized and tested the proteins designed by Claude in the lab. Out of 1,320 designs, 354 were successful, yielding an overall hit rate of approximately 27%.

Anthropic notes that typical hit rates for such protein design tasks are generally between 10% and 15%. Anthropic also emphasized that successfully designing a protein capable of binding a target is merely an early stage in drug development, requiring extensive further experimentation and clinical validation.