Leslie M. Thompson, a professor at the University of California, Irvine, has secured nearly $12 million from the California Institute for Regenerative Medicine (CIRM) to lead a clinical trial testing a new neural stem cell therapy for Huntington's disease.
The funding will support an initial human study focused on evaluating the safety and tolerability of an embryonic stem cell-derived neural stem cell product. Currently, there are no treatments that alter the progression of Huntington's disease, making this trial significant for patients and their families.
The planned study aims to determine if the neural stem cells can protect brain cells, repair damaged circuits in the brain, and slow or prevent disease progression. This marks the first time embryonic stem cell-derived cells will be tested in people with Huntington's disease; previous research used fetal cells or tissue. The clinical trial is scheduled to begin in mid-2026.
Huntington's disease is a genetic disorder that destroys brain cells over time, typically starting between ages 35 and 50 and worsening over one to two decades. Symptoms include involuntary movements, cognitive difficulties, and mood changes.
The therapy under investigation—hNSC-01—uses neural stem cells designed to protect existing brain cells from dying, replace lost cells, rebuild impaired circuits in the brain, release beneficial proteins such as BDNF (which are low in patients), and reduce harmful protein accumulations. Animal studies have shown these effects along with improved movement and restored brain function.
UC Irvine’s clinical trial will enroll 21 individuals with early-stage Huntington’s disease: 12 participants will receive escalating doses in Phase 1B while nine more will join a Phase 2A expansion group. The treatment involves surgical delivery of the cells into the brain followed by close monitoring for safety and early signs of benefit.
Hospital costs for Huntington’s patients in California can range from $3 million to $25 million annually. If successful, this therapy could help people maintain independence longer and lower long-term care expenses.
"This trial is an exciting step for regenerative medicine and its potential to change the course of Huntington's disease," said principal investigator Thompson. "It provides additional hope to patients and families who currently have very few options."
She also noted: "The award is the culmination of a tremendous effort from a team of investigators, including Dr. Jack Reidling and Yuna Muyshondt at UC Irvine and the UC Davis GMP facility that produced the cell product."
Thompson has spent more than thirty years researching Huntington’s disease and has received $17.6 million from CIRM to advance both basic science and translational research on this topic. In 2019 she was awarded $6 million for developing stem cell-based therapies; this work cleared an investigational new drug application with the FDA, enabling this current clinical trial through UC Irvine Alpha Clinic.
Earlier this year Thompson received another $2 million from CIRM to study why certain brain cells are more vulnerable than others in Huntington’s disease using patient-derived stem cells alongside advanced molecular techniques.
This project falls under CIRM’s Clinical Trial Stage Projects initiative aimed at moving promising stem cell therapies through late-stage preclinical development into clinical trials targeting unmet medical needs.
