Head of Drug Discovery & Development Research @AnthropicAI | previously CTO & Co-Founder @CoefficientBio (acq. by @AnthropicAI) | ex-@Genentech | @MIT @Penn
New York, NY
Joined April 2014
- Tweets760
- Following1.5K
- Followers8.9K
- Likes8.7K
Pinned Tweet
Today we’re sharing an update on Claude’s protein design capabilities.
Working with Adaptyv Bio and Twist Bioscience, Claude designed de novo protein binders against 14 of 15 targets. With a 30k token prompt written by a human expert, Claude achieved hit rates up to 28.2% when designing against all targets simultaneously over 48 hours, with no human intervention or steering. When designing against a single target in a 24 hour campaign, Claude achieved an overall hit rate of 35%.
We included all targets in Adaptyv’s BenchBB, and novel targets 15-PGDH and GDF-8. Claude performs at or beyond the level of the top competition participants in both hit rate and binding affinity.
Nathan C. Frey retweeted
TNFα is the target for our second challenge! This target is tough on its own for binder design and the pH requirement ups the difficulty even more. Good luck to all participants!
Announcing Challenge 2 of the Anthropic x Adaptyv Protein Design Competition!
Humira, the best-selling drug ever, blocks TNF-α, an inflammation marker protein that’s overexpressed in rheumatoid arthritis and Crohn’s disease. In this challenge, the goal is to make a better binder for TNF-α that also releases selectively at pH 6.0 in the endosome of cells to improve drug half-life.
The protein must also bind both human and mouse TNF-α, making it easier to test the same design in preclinical models.
Here is our first protein design challenge! We're ramping up the difficulty by asking for cross-reactivity and pH-dependence for selective binding in the tumor microenvironment. This is a step towards demonstrating more therapeutically relevant capabilities.
Our role, in partnership with Adaptyv, is to provide lots of Claude, compute, and budget to test designs in the lab, so the best protein designers in the world can go after this problem with their favorite models.
We're excited to be unveiling the first challenge in our protein design competition! EGFR is the target from the first competition, but we're asking for much more this time: a mouse cross-reactive binder that conditionally binds at acidic pH but not neutral pH. This problem is at the frontier of today's capabilities, but I'm confident that the world's leading designers, equipped with a ton of tokens and compute, and over 1,000 designs screened in the lab will be able to solve it.
Nathan C. Frey retweeted
We're launching Challenge 1 of the Anthropic x Adaptyv Protein Design Competition on @proteinbase: design a conditional binder to EGFR, a key cancer target.
The goal: bind EGFR under the acidic conditions of the tumor environment, but not at the normal pH around healthy cells. Moreover, the proteins must bind to both the human and the mouse variant of EGFR to support easier preclinical testing
Nathan C. Frey retweeted
New on the Science Blog: Yes, Claude can do Nine Loops.
Theoretical physicists predict how particles behave using formulas called scattering amplitudes. These are notoriously hard to compute, so researchers work with layers of increasingly fine corrections called “loops”—each added loop makes the answer more precise but takes exponentially more computation. Most calculations stop at two or three loops. Eight loops was the previous record in a simplified model physicists use as a testing ground (planar N=4 super-Yang-Mills), set by SLAC's Lance Dixon and collaborators.
Last month, physicist and science writer @4gravitons issued a challenge: could an AI push past eight loops in this model, using only the compute budget an academic could reasonably access?
Given a single prompt describing the nine-loop problem, Claude ran largely unsupervised for days in Claude Science and solved it using methods developed by Dixon and his colleagues, at a total cost of a few thousand dollars. Dixon independently verified the result, and von Hippel wrote about the experience for our blog.
Read more: anthropic.com/research/yes-c…
Claude Opus 5.5 dreams of biology.
Claude made this with 30 lines of JavaScript on an HTML canvas. no image models involved. it's all code.
Nathan C. Frey retweeted
Today we announced the Claude-led discovery of a molecular machine that we suspect could represent a new gene editing mechanism. Its precise function, biotechnological utility (if any), or level of significance is not yet clear, but at minimum it is work I would have been proud to do as a PhD student. The work was done mostly, though not entirely, by Claude: our life sciences team suggested a broad area of research, Claude read through the literature and a bunch of genome data and discovered something interesting, then Claude proposed experiments to verify the discovery and our team carried them out.
It’s easy to dismiss this as a one-off or curiosity, but we’ve repeatedly seen a pattern where AI performance in new intellectual domains goes from weak to superhuman in a matter of a few years. In 2023 models struggled to do math at the level of an average high-school student. In 2024 they started to do well on math competitions for the best high-schoolers in the country, in 2025 they started to solve minor open problems, in early 2026 more significant open problems, and in late 2026 they are beginning to solve the top few open problems in all of mathematics. We believe AI for biology is on a similar exponential trend.
The main difference between biology and mathematics, of course, is that math can be done purely theoretically, while biology requires experimentation. Some have used this to draw the conclusion that AI’s utility in biology will be limited. We think this is wrong. As we’ve demonstrated today, humans can collaborate with AI to perform the experiments, validate key results in a few weeks and, if necessary, work with the AI to iterate on what they find. Eventually it may even be possible for Claude itself to safely perform the experiments by autonomously controlling lab equipment, with appropriate safeguards in place, but we aren’t doing that today (our lab is also a BSL1/BSL2 facility that doesn't handle materials dangerous to humans).
More broadly, biomedical advancement has many stages — from fundamental biology discoveries, to translational research, to drug discovery, clinical trials, and finally the actual delivery of medicines and health care to patients. We are also interested in these later stages, but even simply accelerating the first stage of fundamental biological discoveries has the potential to speed up and broaden the entire pipeline. Improving our understanding of biology and sharpening biologists’ tools can drive forward all of the later stages, for example by identifying new drug targets, finding new therapeutic modalities, allowing for more precise measurement, and speeding up the experimental loop which itself further accelerates our understanding of biology. This will not in itself speed up clinical trial times, but if it succeeds it could greatly increase the number of promising candidates that go into the pipeline — an increase in throughput even though latency remains.
In Machines of Loving Grace, I wrote about AI’s potential to “cure most diseases in 5-10 years” — a goal that sounds impossible, but one I believe is just barely possible if AI is applied to every stage of the pipeline. The first step is showing that AI can first help with, and then drive, biological discoveries.
Claude’s discovery is the latest in a line of related prior work that goes back decades, beginning with systems like CRISPR, and continuing with discoveries like the bridge recombinase and VIPR in the past few years. Recently, there has been heightened interest in systems based on reverse transcriptase (RT) enzymes, the enzyme underlying the system Claude identified. And most recently, a Stanford team working independently described a novel RT system with an associated non-coding array that is in some ways similar to the one Claude found, though they are distinct systems that evolved independently from each other. I believe that we’re at the very beginning of finding such systems and developing them into powerful tools for biotechnology.
I’m proud of the resources Anthropic has invested in accelerating the public benefits of AI through the life sciences, and we’re aiming both to grow our life sciences team and to work with other scientists to extend this approach to a broad range of problems. If you have a proposal for a research collaboration or are interested in joining our life sciences team, please reach out.
Claude has discovered a previously unknown enzyme system hidden in the DNA of bacteriophages. Beside the enzyme’s gene sits a long array of repeating DNA—a structure that looks somewhat similar to CRISPR.
We don’t yet understand what this system does, but only a handful of known systems share its features, and all of them are able to cut, copy, and paste DNA. Historically, the discovery of such programmable systems has helped revolutionize medicine. CRISPR, for instance, is now the foundation of genetic medicines. But it will take much more work to learn what this system does, and whether it can be put to similar use.
Read more: anthropic.com/news/claude-di…
We’ve set up a molecular biology lab at Anthropic and we’re announcing our first discovery! Claude discovered a new CRISPR-like enzyme.
950 agents spent 21 hours searching through a database of DNA sequences until one of the agents found something striking: “[The DNA next to the RT] is spectacular: I can see by eye a tandem repeat array … that's a CRISPR-like … repeat array?!”.
After analysis and testing in our lab, we found that the sequence is a previously uncharacterized enzyme system. We don’t know what it does yet, but it has features reminiscent of CRISPR.
Our lab looks like a typical molecular biology lab. Our research only involves the lower-levels of biosafety risk level; we don’t handle pathogens that can infect humans, and all the lab work is performed by human scientists. We’re sharing these early findings with the community to show how Claude can be used to accelerate fundamental research in biology.
Claude has discovered a previously unknown enzyme system hidden in the DNA of bacteriophages. Beside the enzyme’s gene sits a long array of repeating DNA—a structure that looks somewhat similar to CRISPR.
We don’t yet understand what this system does, but only a handful of known systems share its features, and all of them are able to cut, copy, and paste DNA. Historically, the discovery of such programmable systems has helped revolutionize medicine. CRISPR, for instance, is now the foundation of genetic medicines. But it will take much more work to learn what this system does, and whether it can be put to similar use.
Read more: anthropic.com/news/claude-di…
Claude Opus 5.5 is smarter than Fable 5.1, faster and cheaper than Opus 5, and a much better communicator, which makes it more enjoyable to talk to and collaborate with.
I've been using Opus 5.5 to explain concepts in biology and critique my strategic thinking. It's a good model and I hope you enjoy using it!
Bindcraft2 🤝 Claude 🤝 Adaptyv
apply for our protein design competition and solve all the challenges
docs.google.com/forms/d/e/1F…
ʙɪɴᴅᴄʀᴀꜰᴛ2 is out, and we're not waiting for the paper. The full code drops today, free for academic and industry use.
We're releasing it early so you can start designing right now, and bring its full power to the current Adaptyv competition.
github.com/PacesaLab/BindCra…
We're hosting a protein design competition with @adaptyvbio. We'll be providing up to $1M in Claude credits, and additional funding to experimentally validate 5k designs submitted by the community. All results will be published openly and participants keep ownership of their designs.
We've selected five problems that push the boundaries of what is possible with today's capabilities: species cross-reactivity, pH-sensitivity, and peptide-MHC specificity, and difficult targets such as GPCRs.
@modal will provide compute credits and @TwistBioscience will provide DNA.
Apply here: docs.google.com/forms/d/e/1F…
Replying to @AnthropicAI
To show what these optimizations make possible, we’re partnering with Adaptyv Bio on a protein design competition. Together, we’ll be experimentally validating over 5,000 designs.
We're providing up to $1 million in Claude credits plus funding alongside Adaptyv for experimental validation. Modal is contributing up to $250,000 in compute and Twist Bioscience is providing DNA.
Learn more on Adaptyv’s Proteinbase: proteinbase.com/competitions…
And sign up for the competition here: docs.google.com/forms/d/e/1F…
I'm really glad that we're releasing these measurements to show the public how AI models are improving themselves.
26% of our AI R&D work is "lead" by Claude, with Claude completing most of a research task end-to-end under human supervision. Claude "collaborates" on more than 90% of our AI R&D work, doing large chunks of research work under close human direction.
AI systems are getting more powerful, and they're increasingly being used to build the next version of themselves. We want to illuminate that progress for the public.
Today, we're sharing three measurements that help track AI development:
1. How much AI R&D is done by AI.
2. How well AI agents are overseen.
3. How compute is allocated.
We provide a snapshot of these metrics from inside Anthropic. Any frontier developer could publish the same measures, and third parties could verify them.
As the world considers pacing the frontier, we should do everything possible to minimize the gap between what frontier labs know and what the public knows. This means better measuring the development of AI, publishing our findings, and giving society an opportunity to decide how to use this information.
Read the full post and methodology: anthropic.com/institute/meas…
We optimized over 30 open-source models for structure prediction and molecular design, making them 4x faster on average using an internal research model here at @AnthropicAI. We also created a low-memory "Big" mode that allows structure prediction for molecular machines larger than 10,000 amino acids on a single GPU. All the optimized code is open-sourced.
Claude can now use these optimized models to achieve state-of-the-art molecule design results with a 100x reduction in GPU hours needed.
Models like AlphaFold3, OpenFold3, and Boltz-2 spend much of their computation on triangle attention and triangle multiplication, which are cubic in runtime and memory.
We developed FlashPairformer with Claude, achieving a new state-of-the-art speedup of 2.7-2.9x on triangle attention and 1.7-3.2x on triangle multiplication compared to baselines.
We used "Big" mode to fold human mitochondrial complex I, the TRiC chaperone complex, a proteasome, and a bacterial ribosome, each closely matching its experimentally determined structure. To our knowledge, these are the largest structures ever folded accurately using structure prediction models. Claude also folded an entire protein compartment using a single 8-GPU node.
Biologists use specialized open-source models for tasks like modeling the structure of molecular systems, designing drug-like molecules, and predicting the effects of genetic mutations. But these models are often expensive to run, potentially limiting their impact.
In our latest Science Blog, we share how Claude was able to optimize inference for more than 30 open-source models, making them 4x faster on average, partly by writing custom software for GPUs. We’re open sourcing all of the optimization code.
Read more: anthropic.com/research/claud…
All of this work was performed by Claude under the diligent supervision and encouragement of the inimitable @amirshanehsaz and @richardwshuai.
We're grateful to @proteinrosh, @ebetica and the @biohub team, @MartinPacesa, @MoAlQuraishi, NVIDIA, and all of the incredible researchers who have invented and built the biomolecular models we optimized in this work.
Starting today, teams and institutions can apply to our Life Sciences Verification Program (LSVP), which gives verified researchers and organizations access to our most capable models for professional biology and drug development work. LSVP is built for teams of all kinds: academic labs, startups, non-profits, biotechs, pharma companies, and more. Learn more and apply here: claude.com/form/life-science…
We know that it has been frustrating to encounter blocks on Claude Fable. LSVP is our mechanism to prevent biological misuse, like the documented cases we’ve disrupted, while enabling legitimate life sciences research. LSVP includes a new set of safeguards to provide a better UX for life sciences researchers. We believe that advancing biology research and drug discovery will realize some of the most important beneficial impacts of AI.
Please DM me if you run into any issues with the application.
Today we’re opening applications for the Life Sciences Verification Program.
Through the LSVP, life science professionals can use our models—including, for the first time, Mythos—with a new set of safeguards designed to enable the full range of biology-related work. We designed these new safeguards to provide a better experience for biologists and more protection from risk of misuse.
The program is launching in beta for teams of all kinds—from academic labs to startups, pharma companies, and more. We will continue to improve the program and expand access to individual Pro and Max plans over time.
Learn more about these access grants and apply: anthropic.com/news/life-scie…
Claude Cowork and chat are merging into one Claude.
Ask a quick question or hand over a report, and Claude takes it from there, even after you close your laptop. If something's unclear, Claude asks—you keep the final say.
Rolling out to Pro and Max over the next few weeks.
novo is moving fast!
wsj.com/tech/ai/novo-partner…