Xaira Therapeutics Appoints Biotech Exec Behind Belharra and Ambys as President and COO to Scale AI-Driven Drug Discovery Platform
Xaira Therapeutics, the AI-native biotech launched in 2024 with over $1 billion in funding, has appointed biotech executive Jeff Jonker as President and Chief Operating Officer. Jonker will report to CEO Marc Tessier-Lavigne and oversee operational functions as Xaira advances its AI-driven platform for therapeutic development.
Jonker brings over two decades of leadership experience across private and public life sciences companies, including CEO roles at Belharra and Ambys Medicines, and senior positions at NGM Biopharmaceuticals, Genentech, and Theravance. At NGM, he led pipeline expansion efforts and helped establish a major strategic partnership with Merck. He began his career as a corporate attorney at Wilson Sonsini.

Jeff Jonker
At Xaira, Jonker will help scale the company’s technical and therapeutic programs as it builds an integrated drug discovery engine combining large-scale biological data generation, generative modeling for molecule and antibody design, and predictive tools for translational research and trial optimization.
The appointment follows a series of key moves at Xaira, including the recent recruitment of Dr. Bo Wang as SVP and Head of Biomedical AI. Wang, a CIFAR AI Chair and professor at the University of Toronto, leads efforts to build foundation models that characterize complex disease biology and guide precision therapeutic development.
See also: 13 Foundation Models: Startups, Industry Updates and the Nobel Prize
Last month, the company released X‑Atlas/Orion, a genome-wide Perturb-seq dataset covering 8 million single cells, reportedly the largest public resource of its kind. Generated using Xaira’s in-house FiCS Perturb-seq platform and 10x Genomics’ Chromium system, the dataset includes transcriptional profiles from perturbations of all human protein-coding genes. Xaira has paired the resource with a computational pipeline that models gene suppression on a continuous scale, allowing higher-resolution insights into gene function and pathway architecture.
The dataset is intended to support the training of "virtual cell" models—AI systems that simulate cellular responses to genetic or pharmacologic perturbations. According to the company, this modeling approach underpins its broader platform for de novo protein design, therapeutic target discovery, and in silico validation.
Xaira’s scientific direction reflects contributions from co-founder David Baker, co-recipient of the 2024 Nobel Prize in Chemistry, and a team of leaders spanning academia, pharma, and AI. Backed by ARCH Venture Partners, F-Prime Capital, NEA, Sequoia, and Foresite Labs, the company is headquartered in the San Francisco Bay Area with additional operations in Seattle.
Topics: Startups & Deals