AA urethral stricture is scarring in the tube that carries urine out of the body. If untreated, it can be intensely painful and lead to kidney stones and infections. That’s why the CIRM Board is investing more than $3.8 million in a Phase 1 clinical trial to use stem‑cells to treat scarred urethras.

This is the 81st clinical trial funded by CIRM.

When scarring forms along the urethra, it blocks urine flow. This causes complications. James Yoo, M.D., Ph.D., and his team at Wake Forest University Health Sciences will use epithelial and smooth muscle cells from the patient’s bladder. They’ll layer them onto a synthetic tubular scaffold. Surgeons will then implant the tube into the urethra.

The goal is for the progenitor cells to support tissue self‑renewal. This allows the structure to fully integrate into surrounding tissue, restoring normal urinary function. Dr. Yoo and his team believe the approach could remain effective for at least a decade.

“While not immediately life‑threatening, urethral strictures lead to multiple health problems that impair quality of life and predispose patients to kidney dysfunction,” said Dr. Maria T. Millan, CIRM President and CEO. “Developing a durable, effective treatment could significantly improve lives and reduce long‑term healthcare costs for recurrent stones, infections, and downstream kidney complications.”