Xaira Therapeutics emerged from stealth on Tuesday with plans to tap the biological equivalent of artificial intelligence image generation tools designed to create molecules that hit hard-to-drug targets.
Xaira Therapeutics, described as an integrated biotechnology company, launched
The San Francisco-based startup has brought together big names in AI research, drug development and venture capital to build and use an R&D platform. ARCH Venture Partners and Foresite Labs jointly incubated the biotech and contributed funding. The funding from ARCH, which lists Alnylam and Illumina among its successes, is the largest initial commitment in the almost 40-year history of the fund.
Robert Nelsen, managing director and co-founder of ARCH, explained the thinking behind the big bet. “We have reached the point where AI finally allows us to see biology in new ways, and translate those discoveries to better treatments for disease,” Nelsen said in a statement. “This creates an enormous opportunity for us to rethink drug discovery entirely.”
Xaira will use the money to build on AI research carried out at David Baker’s lab at the University of Washington School of Medicine. Baker, the director of the university’s Institute for Protein Design, and his colleagues developed the RFdiffusion and RFantibody models for protein and antibody design.
RFdiffusion is the biological equivalent of AI image generation tools such as DALL-E. Baker’s lab trained the model to remove noise from clouds of atoms and arrange them into novel protein backbones. Users provide minimal molecular specifications, such as high-affinity binders to a target protein, and the model generates functional proteins. Baker and his colleagues described the model in a Nature paper in 2023.
Xaira, which employs researchers who developed the models, will advance RFdiffusion and RFantibody while working on new methods. Marc Tessier-Lavigne, the former chief scientific officer of Genentech, will oversee the work as CEO of Xaira. Tessier-Lavigne is joined on the executive team by Hetu Kamisetty, Arvind Rajpal and Don Kirkpatrick, who list companies such as Genentech and Meta on their résumés.
Kirkpatrick was chief technology officer at Interline Therapeutics before joining Xaira. The proteomics group at Interline, which Foresite and ARCH launched with $92 million in 2021, is now part of Xaira. The new AI-enabled biotech has also picked up technologies and staff from Illumina’s functional genomics R&D operation.
Xaira is applying the technologies to hard-to-drug targets. As Xaira works to build a pipeline of drug candidates across multiple modalities, the biotech will use data from its lab and clinical experiments to improve its AI and foundation models. Similar feedback loops are at the heart of other biotechs that are using AI and machine learning to make new proteins, such as the ARCH-backed Generate:Biomedicines.
F-Prime, NEA, Sequoia Capital, Lux Capital, Lightspeed Venture Partners, Menlo Ventures, Two Sigma Ventures, the Parker Institute for Cancer Immunotherapy, Byers Capital, Rsquared, SV Angel and others have also contributed funding to Xaira.
Nick Paul Taylor is a freelance pharmaceutical and biotech writer based in London. He can be reached on LinkedIn.
