Fathom Therapeutics (formerly Atommap) is a New York and Boston based biotech building Microcosmos, a drug-design engine that fuses quantum chemistry and AI to simulate how proteins actually move inside living cells. By modeling motion instead of static snapshots - reportedly up to 10,000x faster than conventional simulation - the company hunts for the fleeting binding pockets that make 'undruggable' targets druggable, then designs small molecules, degraders, and molecular glues against them. In April 2026 it raised a $47M oversubscribed Series A led by Sutter Hill Ventures.
Huafeng Xu is the founder and CEO of Fathom Therapeutics (formerly AtomMap), a New York drug-design company that simulates protein motion at atomic resolution to design small molecules that work inside living cells. A computational chemist with 25+ years and 10,000+ citations, Xu spent 12 years at D. E. Shaw Research building the free-energy and molecular-dynamics methods now standard across pharma, then served as CTO of Silicon Therapeutics and Roivant Discovery before launching his own company. In April 2026 Fathom closed an oversubscribed $47M Series A led by Sutter Hill Ventures to scale its Microcosmos engine.