BillionToOne Is Solving One of Biotech’s Hardest Problems

BillionToOne founders David Tsao and Oguzhan Atay explain how they built a $4B liquid-biopsy company from a half lab bench—and why early cancer detection is their next target.

• BillionToOne went public at a $4B valuation and now processes 600,000+ prenatal tests per year, holding ~20% U.S. market share.
• 1 in 11 babies born in America is screened by a BillionToOne test that did not exist a decade ago.
• Core innovation: adding synthetic DNA to blood samples before PCR amplification, then using ML to subtract noise—turning a biology problem into a math problem.
• Two months after their first commercial launch they had exactly one physician sending one or two tests per week; emergency sales hiring saved the company.
• They started with $300,000 and a shared half-lab-bench; first fundraise of $300K took six months at roughly $10K per check.
• Step three roadmap: detect microscopic residual tumor DNA post-surgery in stage 1-2 cancer patients, where 20% have undetectable remnants that cause relapse.
• Step four (ultimate goal): annual blood-screen for the general population to catch cancer before stage 1—what they call the holy grail of cancer detection.
• They hire interdisciplinary scientists who own full end-to-end product development, reporting directly to founders, creating a portfolio of internal startups within the company.

2026-04-06 · Watch on YouTube