Doctors at Keck Medicine of USC are implanting lab-grown, dopamine-producing cells into the brains of people with Parkinson’s disease in an early-stage clinical trial that will enroll up to 12 participants across three U.S. sites.
Parkinson’s disease is a long-term neurological condition that gradually worsens over time. More than one million people in the United States are living with the disorder, and about 90,000 new cases are diagnosed each year. Current medications and therapies can ease symptoms, but no treatment has been proven to stop or slow the disease itself.
The condition is closely linked to a drop in dopamine levels in the brain. Dopamine is a chemical messenger that plays a critical role in controlling movement. As dopamine-producing brain cells progressively die off, the brain loses its ability to properly regulate movement, contributing to hallmark symptoms such as tremors, muscle stiffness and slowed movement.
Researchers at Keck Medicine of USC are testing whether specially engineered stem cells can help restore dopamine production in an early-phase clinical trial called REPLACE™. The approach uses induced pluripotent stem cells (iPSCs)—adult cells, such as those from skin or blood, that are reprogrammed into a versatile state and then guided to develop into dopamine-producing brain cells.
To deliver the cells, neurosurgeon Brian Lee, MD, PhD, creates a small opening in the skull and, using magnetic resonance imaging (MRI) guidance, places the cells into the basal ganglia, a brain region involved in coordinating movement. “If the brain can once again produce normal levels of dopamine, Parkinson’s disease may be slowed down and motor function restored,” Lee said.
After the operation, participants are observed for 12 to 15 months to track symptom changes and monitor for potential side effects, including dyskinesia—excess movements—or infection. Researchers plan to follow patients for up to five years.
Keck Medicine is one of three U.S. sites participating in the study, which includes 12 people with moderate to moderate-severe Parkinson’s disease. The stem cell therapy being tested, RNDP-001, is produced by Kenai Therapeutics, which says the U.S. Food and Drug Administration has granted the Phase 1 REPLACE™ trial Fast Track designation, a program intended to speed development and review of therapies addressing serious conditions and unmet medical needs.
Neurologist Xenos Mason, MD, a co-principal investigator, said the team believes the iPSCs “can reliably mature into dopamine-producing brain cells” and help “jump-start” dopamine production. Lee said the long-term aim is to develop a technique that can improve motor function and quality of life.
Mason has received an honorarium payment from Kenai Therapeutics in the past.
