Anthropic has acquired Mithril Medicine, a biotech company with a single full-time employee that has been developing treatments for two rare forms of muscular dystrophy. The AI company disclosed the deal on October 27, 2026, in a research post on its early work in drug development, and named the founder as Cody Tranbarger. According to R&D World, the acquisition closed in July.
Anthropic did not disclose the price or other terms. Mithril was based in Cambridge, Massachusetts, R&D World reported.
Tranbarger has joined Anthropic, where he is continuing Mithril's research and plans to start several new drug programs. Anthropic said that if the drug candidates keep holding up, one could be ready for human clinical trials as soon as late 2028.
What Mithril built
Mithril worked on bispecific antibodies for LAMA2-related congenital muscular dystrophy, an inherited muscle-wasting disease, and on a second program for alpha-dystroglycanopathy, according to R&D World and OfficeChai. Anthropic said the company took a possible treatment for one form of muscular dystrophy from an idea to promising results in mice in less than 18 months.
R&D World described the mouse data in more detail. Seven mice given one antibody format showed roughly twice the grip strength and peak triceps force of four untreated control mice. The study had clear limits: treatment was assigned by litter rather than at random, and the treated group was tested 126 to 161 days after the controls. Anthropic's technical report, which has not yet been peer reviewed, calls for a blinded repeat run at the same time as controls.
Mithril aims to choose formal drug candidates in 2027, R&D World reported. The LAMA2 program could reach human trials in late 2028 if development succeeds, and the alpha-dystroglycanopathy program as early as 2029.
“If we get it right, the result will be more programs, higher hit rates, and broader patient impact”
A company run with Claude
What made Mithril unusual was its size. Tranbarger was its only full-time employee, supported by eight paid consultants and advisers, according to R&D World. He used Claude, Anthropic's AI model, to organise contracts, logistics and experiments at 11 outside laboratories, which produced antibodies, measured binding, ran cell assays and carried out the mouse studies.
R&D World reported that Claude summarised a 341-page production report covering 113 antibody constructs in under eight minutes, and that Anthropic says planning a new program now takes two to three days with Claude, compared with one to two months without it. The team also reviewed six mistakes made by Claude. At least three of them reached the outside labs, and two errors in reviewing production data went unnoticed for more than four days.
Tranbarger calls the approach "Pipeline-in-a-Person": the idea that one scientist with enough AI help could run several drug programs in parallel, OfficeChai reported. Anthropic plans to test that model across more rare-disease programs.
The founder and the backers
Tranbarger holds a 2025 joint MS and MBA in biotechnology from Harvard, according to R&D World. He started as an investment banking analyst at Goldman Sachs and later worked at Casdin Capital and Prime Medicine before becoming an entrepreneur-in-residence at Atlas Venture, the Cambridge biotech venture firm.
OfficeChai reported that he founded Mithril with Atlas about 18 months before the acquisition and that Atlas provided a seed round. The amount was not disclosed. On the day of the announcement, Tranbarger also revealed that he was behind Professor Oak, a pseudonymous biotech and venture capital account on X that he had run for six years, OfficeChai said.
Why Anthropic is buying
Anthropic published the acquisition alongside early results from six drug-development partners: BigHat Biosciences, Bristol Myers Squibb, Divergence Labs, Enveda, Generate Biomedicines and The Column Group. Their work ranges from antibody design and lead optimisation to regulatory documents and clinical trial planning. Anthropic said most of it is still preclinical, and that it plans to extend Claude's role into clinical trials as programs advance.
OfficeChai noted that Mithril follows Anthropic's purchase of Coefficient Bio earlier in the year for roughly $400 million, and that Mithril's programs were folded into Anthropic's in-house drug discovery work. Tranbarger said he would use the move to see how many programs one person can realistically run at once, and to bring the model to the wider drug industry.
