HexemBio Secures $10.4M to Advance Blood Stem Cell Rejuvenation Therapy for Cancer Treatment
Key Insights
HexemBio (search) emerged from stealth with $10.4 million in seed funding led by Draper Associates (search) to develop a novel blood stem cell rejuvenation therapy using its Synthetic Human Yolk Sac (search) platform.
The company's approach recreates the embryonic environment where blood stem cells first form, avoiding the safety risks associated with gene editing or chemical reprogramming methods.
HexemBio (search)'s lead program targets bone marrow transplant outcomes in blood cancers (search) including acute myeloid leukemia (search) and acute lymphoblastic leukemia (search), having received FDA Orphan Drug Designation.
HexemBio (search) has emerged from stealth with $10.4 million in seed funding to advance what it describes as the first blood stem cell rejuvenation therapy, targeting improved outcomes for bone marrow transplant patients with blood cancers (search). The Berkeley and New York-based biotech company's funding round was led by Draper Associates (search), with participation from SOSV (search), Seraphim (search), and other strategic investors.
Novel Approach to Stem Cell Rejuvenation
The company's proprietary platform, called the Synthetic Human Yolk Sac (search), represents a departure from conventional stem cell therapies. Rather than editing or chemically reprogramming aged hematopoietic stem cells, the technology temporarily places a patient's own cells into a recreated version of the developmental environment where blood stem cells first emerge in the embryo, then returns them via standard IV infusion.
"Most innovations in bone marrow transplant rely on the use of harsh treatments such as high levels of cytokines, or genetic engineering which can stress or often exhaust stem cells," said Gabriel Levesque Tremblay, CEO and co-founder of HexemBio (search). "Our co-founders asked a different question: what if we simply gave aging stem cells back the environment they had at the beginning of life?"
Hematopoietic stem cells sit deep in the bone marrow and give rise to every blood and immune cell in the human body. Their decline with age is linked to weakened immunity, chronic inflammation, and increased susceptibility to conditions including blood cancers (search) and neurodegeneration.
Scientific Foundation and Clinical Target
Foundational work supporting the platform was published in Nature in February 2024, by a team led by Mo Ebrahimkhani at the University of Pittsburgh, with Samira Kiani and Joshua Hislop among the authors. All three are now co-founders of HexemBio (search), with Ebrahimkhani serving as chief scientific officer.
The company's lead clinical program targets bone marrow transplant in patients with blood cancers (search) including acute myeloid leukemia (search) and acute lymphoblastic leukemia (search). HexemBio (search) received FDA Orphan Drug Designation for this indication in July 2025 and completed its FDA Pre-IND meeting in January 2026, with first-in-human trials targeted for 2027.
The regulatory strategy focuses on bone marrow transplant outcomes because aging itself is not currently recognized as a regulatory indication, a constraint that has shaped how several longevity-adjacent biotechs have structured their early clinical programs.
Leadership and Advisory Support
The founding team spans MIT, UC Berkeley (search), Harvard (search), and Y Combinator. Levesque Tremblay, a former YC founder and UC Berkeley postdoc, serves as CEO. Samira Kiani, a Presidential Early Career Award recipient who trained at MIT, is CTO. Joshua Hislop, whose doctoral work contributed directly to the Nature publication, leads the company's AI platform, which includes proprietary tools called YolkGPT and YolkScore.
The advisory board includes Robert S. Langer, Institute Professor at MIT and co-founder of Moderna, who called the approach "fundamentally different from transcription-factor reprogramming or gene editing" and said the early data were "extremely compelling."
Additional advisors include Peter Barton Hutt, former chief counsel of the FDA and current Moderna board member; Joanne Kurtzberg of Duke University, one of the leading bone marrow transplant clinicians in the US; and George Church, professor of genetics at Harvard (search) Medical School and co-founder of Colossal Biosciences.
Investment and Development Timeline
"HexemBio (search) discovered a way to renew a patient's own stem cells rather than chemically or genetically reprogramming them," said Tim Draper, founding partner at Draper Associates (search). "That kind of foundational biological innovation is exactly the type of high-conviction investment we look for."
The seed funding will be used to complete IND-enabling studies and GMP manufacturing ahead of the 2027 trial target. Previous attempts to reverse stem cell decline have typically involved transcription-factor reprogramming, cytokine treatments, or gene editing, approaches that can push cells into unstable states or carry safety risks that HexemBio (search) says its method sidesteps.