Valthos Raises $30M from OpenAI, Lux Capital, Founders Fund to Build Next-Generation Biodefense

Valthos develops frontier AI systems that identify biological threats and design medical countermeasures in real time.

SAN FRANCISCO, Oct. 29, 2025 /PRNewswire/ -- Valthos announced $30 million in seed financing led by OpenAI Startup Fund, Lux Capital, and Founders Fund to support the development of next-generation biodefense systems.

Increasingly powerful and accessible tools for biological engineering will drive medical breakthroughs, but also introduce a new landscape of biological threats from sophisticated adversaries and individuals.

"The issue at the core of biodefense is asymmetry," said Kathleen McMahon, co-founder of Valthos. "It's easier to make a pathogen than a cure. We're building tools to help experts at the frontlines of biodefense move as fast as the threats they face."

Valthos builds AI systems to rapidly characterize biological sequences and compress the time to design medical countermeasures.

"In this new world, the only way forward is to be faster. So we set out to build a new tech stack for biodefense," said Tess van Stekelenburg, co-founder of Valthos. "This software infrastructure strengthens biodefense today and lays the groundwork for the adaptive, precision therapeutics of tomorrow."

Founded by Tess van Stekelenburg, partner at Lux Capital, and Kathleen McMahon, former head of Palantir's Life Sciences division, Valthos brings together a team spanning software engineering, ML development, and biotechnology. The founding team consists of engineers from Palantir and DeepMind, and computational biologists from Stanford's Arc Institute and MIT's Broad Institute.

"Technology is moving fast. An industrial ecosystem of builders, companies and solutions further democratizes AI to provide broad resilience, and ensures the U.S. continues to lead as AI increasingly powers everything around us. As AI and biotech rapidly advance, biodefense is one of the new industry verticals that helps maximize the benefits and minimize the risks," said Jason Kwon, OpenAI's Chief Strategy Officer. "Valthos is pushing the frontier of protection and defense in one of the most strategic intersections of multiple world-changing technologies, and with the team to do it."

With this funding, Valthos will scale software infrastructure for government and commercial stakeholders and expand its engineering team.

About Valthos

Valthos builds next-generation biodefense. The company harnesses computational methods to characterize biological sequences and design adaptive countermeasures, helping government and life sciences stakeholders respond to emerging threats with speed and precision. Additional information is available at valthos.com.

SOURCE Valthos Inc