SOSV portfolio company HexemBio recently spoke with Axios following its new $10.4 million Seed funding led by Draper Associates, with participation from SOSV, Seraphim, and others.

The company is tackling a core driver of aging: the decline of blood stem cells that power the immune system. While past approaches (gene editing, chemical treatments, or transcription-factor reprogramming) often introduce instability or safety risks, HexemBio takes a different path.

Its Synthetic Human Yolk Sac recreates the environment in which blood stem cells first form. By temporarily placing a patient’s own stem cells into this regenerative environment outside the body, the technology restores youthful function before returning the cells through a standard IV infusion.

Published in Nature, the platform has already earned FDA Orphan Drug Designation for bone marrow transplant. With a completed FDA Pre-IND meeting, HexemBio is now advancing toward human trials in early 2027.