Anthropic's Claude Designs Drug-Binding Proteins at 35% Hit Rate, Crushing Human Experts
Claude autonomously designed protein binders against 14 of 15 drug targets with hit rates roughly double the field standard, backed by wet lab validation.
- Claude designed protein binders for 14 out of 15 drug targets, autonomously and end-to-end.
- Hit rates hit 22-35% versus the 10-15% industry baseline for de novo binder design.
- Against RBX1, Claude scored 40% vs 3.7% for human competition entrants, beating the winning design.
- Opus 4.8 produced cross-species TNFα binders, a target that has defeated multiple expert groups.
- Wet lab validation done independently by Adaptyv Bio and Twist Bioscience.
- Prompts and data open-sourced on Hugging Face; life-science access is gated pending a scientist program.
Designing a molecule that latches onto a specific protein target is one of the ugliest bottlenecks in drug discovery. It normally takes an expert weeks or months per target, sifting through thousands of candidates. Anthropic just handed that job to Claude, and the results have real teeth.
In a new campaign detailed in Anthropic's research post, Claude was given a protein design prompt and left to run autonomously. Claude (Mythos Preview and Opus 4.8) designed protein binders against 15 targets, and succeeded against 14 of them. The hit rates land well above what the field currently produces.
The numbers that matter
A quick primer: a minibinder is a small protein engineered to grab tightly onto a target protein. Binding is the mechanism behind a huge fraction of modern drugs, which either block, activate, or deliver payloads to their targets. Designing one from scratch is called de novo design, and until recently it was the domain of specialists running week-long computational pipelines.
The headline metrics from the campaign:
- Mythos Preview and Opus 4.8 achieve overall hit rates of 26.7% and 22.6% respectively when designing against all targets simultaneously in a 48-hour session
- Mythos Preview achieves an overall hit rate of 35.1% when designing against each target separately using multiple 24-hour sessions
- Industry baseline sits at 10 to 15% in typical protein design campaigns today
- Includes high-affinity binders (sub-10 nM dissociation constants) against at least six targets, and binders matching or exceeding the best reported affinity against at least four targets
Wet lab validation was outsourced to keep Anthropic honest. External evaluators Adaptyv Bio and Twist Bioscience independently produced and tested Claude's designs in the lab.
How the campaign was actually run
This was not a chatbot spitting out sequences. Claude was operating inside Claude Science as an agent, orchestrating a full pipeline of specialist tools. It chose where on each protein target to design against, generated candidate structures and sequences by orchestrating several structure design, sequence design, and co-folding models, ran the designs through multiple cycles of in silico optimization, and computationally screened for novel, diverse candidates that would express, stay soluble, and bind.