I’m delighted to announce @chaidiscovery's collaboration with @pfizer. Their scientists will deploy our AI platform to accelerate drug discovery, including early access to our latest frontier model Chai-3. You can learn more about this partnership and our momentum in @amyfeldman's feature in @Forbes out today forbes.com/sites/amyfeldman/…

Fun to sit down with my friend @SabrinaHalper and talk about Chai's journey. Thanks for having me on!

Memo: What If We're Right? We recently wrote a private letter to partners & friends of a common failure mode: the inability to consistently reason through the daisy chain of downstream consequence when non-consensus, low-probability, events actually occur pages: 1-3

Grateful to share the stage with @robzirk and @BenjamineYLiu at PhRMA Forum today. We are at a critical inflection point for the industry. AI deployment is taking off, and 2026 will be the year get a glimpse of how it will transform the future of medicine.

Great opportunity to work with some of the best in the business

Great coverage from @xiaofei_lin on our deal with @EliLillyandCo and the start of the "year of deployment".

Congrats to @joshim5 @jackdent @chaidiscovery on their first major deal announcement with Eli Lilly! Always amazing to see their pace to adoption. 2026 looks like the tipping point in pharma adoption of AI tools up and down the stack! endpoints.news/eli-lilly-cha…

I’m proud to announce Chai Discovery’s partnership with Eli Lilly to accelerate the discovery of next-generation therapeutics. Through this collaboration, we'll deploy our frontier models, train custom models on Lilly's proprietary data, and create an entirely new toolchain for discovering life-changing medicines.

I'm very excited that we now have results from an almost two-year randomized controlled trial that we ran across thousands of businesses on Stripe: those that accepted a loan from @Stripe Capital grew annual revenue around 27% faster. (Two years isn't that long in the scheme of things, but it is when you're waiting for the results of an experiment you're interested in.) We had two kinds of controls: businesses to whom we offered loans but didn't accept them, and a holdout group of businesses to whom we randomly did not offer loans but which were otherwise identical to those to which we did. As such, we feel confident in the causal nature of this conclusion. While this might not sound like news ("capital increases growth"), I think the finding is a good reminder that many businesses are still quite capital-starved (this effect is on top of all of the other sources of capital that businesses have access to), and it is consistent with what we hear directly from businesses in surveys. Beyond Stripe, inefficient capital allocation at economy-wide scale is likely a major bottleneck to growth around the world. We have an ambitious roadmap planned and we're very much looking forward to expanding worldwide access to growth capital.

The team is @chaidiscovery is truly exceptional... it's a joy to go to work every day with my polymathic group of colleagues.

The @chaidiscovery team is at NeurIPS this week and co-hosting an event Friday night. Ping me if you're interested in AI that transforms drug discovery into an engineering discipline.

autumn @newlimit -- we've advanced our 1st reprogramming medicine through optimization highlights - 8X specificity, 1.6X potency for our lead prototype medicine - 2 TF sets that restore liver function, 20 that restore phenotype - 0 -> 1 preclinical models of endothelial age # engineering therapeutic molecules in september, we selected our first prototype medicine for liver aging to advance toward the clinic. this initiated our first lead optimization campaign to improve the potency & specificity of our prototype. our RNA medicines allow for engineering at the sequence level. RNAs are not translated into proteins equally across cell types, and we can design sequences to maximize activity in our target cells (hepatocytes) and minimize activity elsewhere. our campaign achieved an 8X increase in the specificity of our prototype & a 1.6X increase in the potency within hepatocytes. we believe these optimizations will yield a safer, more effective medicine. # restoring youthful resilience alongside progressing our first asset, we've continued to discover reprogramming payloads that restore youthful function. in october, we discovered 2 payloads that restore youthful resilience to alcohol damage in old livers. these payloads emerged from our discovery screens & validated as prototype RNA medicines. each month, more of these payloads emerge from Discovery Engine, giving us confidence that the well of potential reprogramming medicines is deep. # in vivo T cell reprogramming hepatic reprogramming is only one of several therapeutic applications we’re pursuing. we’ve previously discovered reprogramming payloads that restore youthful cytotoxic capacity and stem-like states to old human T cells. the next stage in the development of these payloads is to test whether they can rescue function in a more complex animal model. before we can test their effects directly, we need to build molecular tools to deliver reprogramming payloads to T cells in vivo. after a series of engineering iterations, we've developed a lipid chemistry that can carry our RNA medicines into T cells in animals. our chemistry is now nearly matching the current state-of-the-art. # measuring endothelial cell age our most recent therapeutic program is focused on restoring function in endothelial cells of the vasculature. we believe improving endothelial function could create renal, cardiovascular, and cognitive health. endothelial cell aging is dramatic enough that we’ve been able to discover functional impairments in just our first few experiments. human endothelial cells are less regenerative in simple in vitro systems, and endothelial injury leads to more dramatic renal damage in old animals. even these early tools allow us to start testing the effect of reprogramming on aged endothelial function, in addition to phenotypes. # join our team we're recruiting talented scientists & engineers across our therapeutic programs and technology teams. reach out if you're excited to create a new class of medicines that add healthy, happy years for ~everyone.

This is an amazing BioAI advance! Antibodies are among the most important biological drugs and save millions of lives; advances in designing them with AI are world changing impact! “86% of our designs possess industry-standard drug-quality properties without any optimization”

after months of antibody design papers that only work on single chains, we are seeing much-needed progress on full IgG congrats to the chai team!

🎉 Thrilled to release our latest technical update. Our latest models can now design antibodies against challenging targets with atomic precision, with developability characteristics on par with approved therapeutics. 💻These results provide a glimpse of a new paradigm, where medicines are design on the computer, and predictive models approach the precision of the wet lab.

We developed a general recipe that allows VLAs to improve from experience. RL is back. (yes, this is 13 hours of coffee making)

Our model can now learn from its own experience with RL! Our new π*0.6 model can more than double throughput over a base model trained without RL, and can perform real-world tasks: making espresso drinks, folding diverse laundry, and assembling boxes. More in the thread below.

Awesome recognition for all the great work the @modal team has done to make building software a delight

🚀 Chai Discovery has been named to the 2025 #Endpoints11 list of the most promising companies in biotech! In just 12 months since our first funding round, we’ve raised $100M and launched Chai-2 — our AI model that can design antibodies with double-digit success rates.

Thank you @Nasdaq for the kind words and for lighting up Times Square! 💙 Excited to keep pushing the boundaries of molecular design with AI.