Drug Discovery AI
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Xaira Therapeutics

South San Francisco company founded in 2023 and launched publicly in April 2024 with more than $1 billion in committed funding, co led by ARCH Venture Partners and Foresite Labs. The stated aim is end to end application of AI across drug discovery and development, combining AI methods research, large scale biological data generation and therapeutic product development, with predictive and agentic models across the whole process.

Its computational core builds on protein design work from the laboratory of co-founder David Baker, awarded the 2024 Nobel Prize in Chemistry, and the research team includes people who developed the RFdiffusion and RFantibody design models; the company also absorbed technologies and staff from Illumina's functional genomics effort and a proteomics group from Interline Therapeutics. Marc Tessier-Lavigne, formerly Chief Scientific Officer of Genentech and president of Stanford University, is chief executive.

In March 2026, after two largely quiet years, the company made its first substantial platform disclosure: X-Cell, a virtual cell model of roughly 4.9 billion parameters built on diffusion language models to predict cellular responses to genetic perturbation, trained on 25.6 million perturbed single cell transcriptomes across sixteen cellular contexts, released with the dataset behind it, X-Atlas/Pisces, and described in a preprint. It had earlier released X-Atlas/Orion, presented as the largest publicly available genome wide Perturb-seq dataset. The stated therapeutic focus is inflammatory and immunological disease, starting with antibodies. No clinical program, named pipeline asset or named pharmaceutical partnership had been disclosed as of this review.

AI Health Index verifiedSeptember 28, 2026
Compare Xaira Therapeutics with other vendors
Founded
2023
Headquarters
South San Francisco, CA
Website
xaira.com
Categories
drug-discovery
Indexed Products
X-Cell, X-Atlas/Pisces, X-Atlas/Orion
Buyer Segments
Pharma / Life Sciences
Assessment

Capability Axes

An AI Health Index grade measures what a buyer can verify from public sources on the date shown. It is not a rating of how good the product is. A vendor can build an excellent system and grade low on an axis because it publishes nothing an outsider can check. How grades read

AI Capability
AA on AI CentralityThe artificial intelligence is the product. Remove the model and there is nothing left to sell.
Vendor Published

The company is its models. Xaira describes itself as building predictive and agentic AI models across the whole of drug discovery and development, with three stated elements: AI methods research, data generation built to feed it, and therapeutic development that is itself treated as a data generating exercise.

Its computational core descends from protein design work by a co-founder's academic laboratory, and its first public product is a model: X-Cell, a virtual cell model that predicts cellular responses to genetic perturbation, released with the perturbation dataset it was trained on. No pipeline asset, service or instrument line exists alongside the models in its published material, so the models are not a layer on anything.

CC on Autonomy and Oversight ModelAutonomy is claimed and oversight is asserted without a mechanism. Human in the loop appears as a phrase rather than a described control.
Vendor Published

Autonomy is claimed and no oversight mechanism is described. The company states that it is building predictive and agentic AI models across the complete spectrum of drug discovery and development, and its stated ambition is to move drug discovery from an empirical science to an engineering discipline. Nothing published says what those agents do, what they may not do, what a scientist reviews before a decision, or at what point a prediction is checked experimentally, beyond a general statement that laboratory and clinical experiments feed model development.

No confidence measure, threshold or failure rate is published for the released model, an unsurprising absence for a company so early in its development.

BB on Model and Technology TransparencyThe approach or the suppliers are named without the version and update discipline behind them. Naming a supplier is the entry to this band both here and on Model Supply Chain Disclosure, which ask different questions of the same disclosure: who receives the data, and what produces the output.
Vendor Published

The approach and the training data are named, without version or update discipline. The company launched X-Cell in March 2026 as its first virtual cell model, describing it as roughly 4.9 billion parameters built on diffusion language models to predict causal perturbation responses across cellular contexts, trained on 25.6 million perturbed single cell transcriptomes spanning sixteen biologically diverse contexts. It released the dataset behind it, X-Atlas/Pisces, and had earlier released X-Atlas/Orion, described as the largest publicly available genome wide Perturb-seq dataset, so the training material is not only characterized but obtainable. Two preprints are named on the company's own news pages with their dates, one on X-Cell (March 2026) and one on X-Atlas/Orion (June 2025), and they may go further into the architecture.

No model version identifier, release note or update practice is published, and no model card accompanies the release.

BB on Model Supply Chain DisclosureSubstantial partial disclosure, or a chain that is structurally short: an in house build, a cleared model that cannot be quietly swapped, or a deployment where the transfer does not occur at all. Naming the model provider exits the band below into this one; the axis rises from here on the completeness of the party list and on the terms that govern data once it arrives.
Vendor Published

A structurally short chain, with the training material released rather than described. The models are the company's own, built by its own research team from academic protein design work its co-founder led, and the data they learn from is generated in house on a platform the company built for the purpose; it published both the perturbation dataset behind its virtual cell model and an earlier genome wide dataset, so the substrate is inspectable rather than asserted. No outside model provider is named as sitting between a question and an answer, and no product is delivered to anyone, so no customer data transfer occurs to enumerate.

What is unpublished is everything around it: no hosting or compute provider for a model of that size, no subprocessor list, and no statement of what would govern a partner's data if a collaboration existed.

BB on Clinical and Operational EvidenceNamed deployments with dated outcome figures and enough method to test them, or published research short of independent validation.
Vendor Published

Published research short of independent validation, and nothing at the program level. The company has put two pieces of work into the public record with dates, a preprint on its X-Cell virtual cell model in March 2026 and one on the X-Atlas/Orion perturbation dataset in June 2025, and released the datasets themselves, which is research others can build on and check. It also reports an industry award for the technologies in September 2026. The preprints may report results in more detail.

At the program level there is nothing: no clinical program, no named pipeline asset, no named pharmaceutical partnership and no customer. The company describes a therapeutic focus in inflammatory and immunological disease with antibodies as the starting point, which is a plan rather than evidence.

DD on AI Safety and PHI StewardshipNothing published on how protected information moves through the system.
Vendor Published

Nothing published reaches the data the models are built on. The only privacy document is a website privacy policy (effective 1 January 2025) covering personal data gathered when someone accesses the company's services and website, with a data security section written for that material.

The company's stated approach is to generate biological and clinical data at scale and to treat every laboratory and clinical experiment as a data generating exercise. Nothing published states the consent basis for human derived material entering that platform, the de-identification standard applied, what is retained, or what would govern a partner's data if a collaboration existed. Safety engineering is not addressed.

Regulatory and Compliance
DD on HIPAA and BAA PostureNo statement of status and no privacy document that reaches the product. Both halves are absent at this grade: a service level privacy document on its own lifts a vendor to the band above even where no status is stated. A website privacy notice, including one that says it does not cover customer data, does not reach the product, so a vendor whose only document is that notice and who states no status grades here.
Vendor Published

No statement of status and no privacy document that reaches the product. The published privacy policy (effective 1 January 2025) covers personal data gathered through the company's website and services; it does not reach the research platform or the biological and clinical data the company says it generates at scale.

No business associate status is stated and no scope position explains how patient derived material would be handled, which is the sentence a company planning clinical development and data generation would need to write. Silence is not a stated position.

DD on Security Certifications and Trust CenterControls are asserted with nothing independent behind them, or nothing is published. Read the note before concluding anything: this is the grade most often corrected on a second pass, because assurance material frequently sits on a parent domain or inside an old announcement rather than on the product pages.
Vendor Published

Nothing independent backs the controls the company describes. No SOC 2 report, ISO 27001 certificate, penetration testing statement, security page or trust center appears on the site. What exists is a data security section in the website privacy policy, describing measures taken to protect personal data collected through the site, with no outside check named.

The company holds a large proprietary biological data platform and says it intends to generate clinical data, which is the material a security posture would need to cover.

CC on FDA and Regulatory StatusNo device claim is made and the product is scoped accordingly. Most administrative and operational products sit here and are not penalized for it, because this axis grades the appropriateness of the positioning rather than possession of a clearance.
Vendor Published

No product is scoped at all yet, and no device claim is made. The company publishes research models and datasets and describes an intention to develop medicines; nothing presents any of it as a regulated product, and no clinical program or regulatory filing is disclosed. A future therapeutic would carry its own position as sponsor. There is nothing here for a regulator's reading of the marketing to contradict.

BB on AI Governance and Bias DisclosureA governance framework with named process behind it, such as certification to an artificial intelligence management standard, or material written for a customer own review committee to evaluate the product with. A framework covering the vendor whole portfolio counts when its scope reaches this product; what it cannot supply is the product specific evaluation the band above asks for. Published results within the one group where the performance of this product is most at risk also sit here: evaluation on the question this axis asks, short of the comparison across groups the band above requires. A medical device clearance or certification, and the quality system behind it, does not reach this band on its own; it is graded under regulatory status. A regulator reviewed plan governing how the model may change does reach it.
Vendor Published

Material exists for an evaluator to work with, but no evaluation of model behavior is published. The company released the dataset its virtual cell model was trained on, and separately released what it describes as the largest publicly available genome wide perturbation dataset, so an outside group can test the model's claims against the same material rather than taking them on trust. Two preprints describing the model and the datasets are named on the company's news pages, and either may describe how the model was evaluated.

Nothing on the company's own site states how the model behaves across the contexts it serves: no breakdown by cell type, perturbation class or data density, no model card, no statement of intended and unsuitable use, and no governance framework. The model's value proposition is generalizing across cellular contexts, which is exactly what that breakdown would show.

CC on AI Liability and RecourseMechanisms exist that let someone challenge an output, such as audit trails, source traceability or review before commit, with nothing standing behind the output and no route for the harmed party.
Vendor Published

One mechanism exists and nothing stands behind an output. The mechanism is release: the company published the datasets its model was trained on, so a third party can retrain, reevaluate and contradict its claims, a stronger form of checkability than a vendor benchmark and the only one the company offers.

Nothing else is published. No accuracy or error rate for the model's predictions appears on the company's own site, though the named preprints may carry figures. No commercial relationship is described at all, so there is no warranty, indemnity or remediation to read, and the published terms and privacy policy cover use of the website.

Integration and Deployment
DD on EHR and Interoperability DepthNo integration evidence. A connector described as available on request grades here until one exists.
Vendor Published

No integration evidence. The company operates its platform internally and sells nothing that connects to anything: for a pharma or biotech partner the record systems that would matter are its research systems, electronic lab notebooks, laboratory information systems, research data platforms and cloud data environments, and none is named or claimed.

The one thing that does move outward is a dataset published for download, which is distribution rather than integration, and the company describes generating clinical data without naming any system it would come from. That is an absence rather than a defect for a company with no product to connect, and nothing says how data and results would move between the company and a partner.

CC on Deployment Model and Data ResidencyA single hosted option with location implied rather than committed.
Vendor Published

An internal platform, with location implied rather than committed. Nothing is delivered to anyone: the models and the data platform are operated by the company from South San Francisco, and the only thing that leaves is published datasets. Nothing states where the models are trained or served, whether outside cloud or compute providers hold the data platform, or how any partner's material would be segregated if a collaboration existed.

Commercial
CC on Commercial TransparencyNo price is published and the posture is discoverable: a buyer can establish how the product is sold and what drives the cost before contacting the vendor. Most of the index sits here.
Vendor Published

The capital is on view and the commercial model is not; no price is published. Nothing says what is for sale: no business model, partnership terms, licensing arrangement, service structure or route of external access appears on the site, and no named pharmaceutical collaboration is disclosed. What is public is the funding, more than $1 billion committed at the April 2024 launch with the investors named, and the governance, with a board whose members are named.

Knowing who funded a company is not knowing how to work with it. The published datasets are free to use, the one thing open to anyone today.

CC on Setting and Specialty CoverageCoverage is claimed broadly without specifics, or stated clearly with nothing validating it yet.
Vendor Published

Coverage is stated clearly with nothing validating it yet. The company describes an end to end scope across drug discovery and development and multiple modalities, with a therapeutic focus in inflammatory and immunological disease and antibodies as the starting point, and its published model works across sixteen cellular contexts. What is not published is a target class, disease area or modality where the platform has produced a result: no program, no partner and no case study appears on the site, so the breadth is a description of intent.

The released datasets do bound one thing usefully: the model predicts cellular responses to genetic perturbation, which is target discovery work rather than molecule design or clinical use.

Tracked Since Listing

What Changed

Material product, regulatory, evidence and commercial changes at Xaira Therapeutics, each verified against a live source and tagged to the capability axis it bears on. Funding rounds and awards are not product changes and are not logged.

Oct 2, 2026Model / architecture

Xaira reported results from the Vega class of its X-Design models, which designed antibodies zero shot, with no data from earlier campaigns. Against its lead oncology target, XA-1, a single design pass produced a progressable binder in three weeks and a preclinical lead in seven, with 17 nM affinity to the human target. Against XA-4, a GPCR where library screening and llama immunization had both failed, a library of 60,000 designs yielded a cross reactive, developable antagonist that has moved into lead optimization.

Bears on: Model and Technology TransparencySource
Our read on this change →Tracked since Oct 2026
Alternatives

Alternatives to Xaira Therapeutics

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Similar is not the same, so check that each one does the job you need. No vendor pays for placement.

Enveda is a clinical stage biotechnology company in Boulder, Colorado that uses AI to discover medicines from the chemistry of living things.

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Antiverse designs antibodies with generative AI for G protein coupled receptors, ion channels and other membrane proteins that conventional antibody discovery struggles to reach, and sells…

Deep Genomics has the deepest scientific record in this category and the thinnest commercial one, and the gap between those two halves is the most useful thing about this entry.

PostEra is the medicinal chemistry counterpart to the biology platforms that dominate this category.

Clinical stage biotechnology company now trading as Verge Labs, applying machine learning to human tissue derived multiomic data in neurology.

Ordered by how closely the graded profiles match across the fifteen axes, inside the same categories. See how each axis is graded in the methodology.

Comparisons

Compared With

Each comparison carries a written verdict, the buyer conditions that favor each vendor, and a graded side by side. Pairs that cross a category boundary are grouped separately, and their verdicts state where the boundary sits rather than manufacturing a head to head.

Commercial

Pricing

Vendor-published figures are labeled as such. Figures labeled “Estimated” are derived from third-party sources and have not been confirmed by the vendor.

Entry Price Pricing Basis BAA Tier Implementation Source
Not applicable
No commercial model disclosed. No partnership, licensing or service structure was identified in public materials. — Not applicable. Vendor Published

A buyer cannot currently determine what is for sale. No business model, partnership terms, licensing arrangement, revenue or route of external access has been publicly disclosed, and no named pharmaceutical collaboration was located in this review.

What is public is the capital: more than $1 billion committed at the April 2024 launch, described as the largest initial funding commitment in ARCH Venture Partners history, co led by ARCH and Foresite Labs with F-Prime, NEA, Sequoia Capital, Lux Capital and Lightspeed participating, at a reported valuation around $4 billion.

Governance is equally visible, with a board including former FDA Commissioner Scott Gottlieb, Nobel laureate Carolyn Bertozzi and former Johnson & Johnson chief executive Alex Gorsky. This is capital transparency without commercial transparency, and the distinction matters: knowing who funded a company is not knowing how to work with it.