Phase 2 Trial of Stem Cell Therapy in Parkinson’s Patients Enrolling

A newly opened Phase 2 clinical trial is evaluating adult stem cells as a potentially disease-modifying treatment for Parkinson’s, building on an earlier study, thought to be the first of its kind, that found a single infusion of these cells safe and well tolerated by patients.

This study will use mesenchymal stem cells, which are found in the bone marrow. These cells are important for making and repairing tissue like cartilage and bone, and may prevent the loss of nerve cells that characterize to this disease.

The trial is actively recruiting up to 45 Parkinson’s patients, ages 50 to 79, at a single site in Houston.

“Studies have shown mesenchymal stem cells can migrate to the sites of injury and respond to the environment by secreting several anti-inflammatory and growth factor molecules that can restore tissue equilibrium and disrupt neuronal death,” Mya C. Schiess, MD, the study’s principal investigator, said in a press release from the University of Texas Health Science Center, where the study will take place.

Inflammation triggered by immune cells is thought to play a key role in driving Parkinson’s.

“The stem cells interact directly with the immune cells,” she added, “leading to an anti-inflammatory state that allows a restorative process to take place.”

Schiess and her colleagues recently published the results of a Phase 1 trial (NCT02611167) of this therapy. Their study enrolled 20 people with mild-to-moderate Parkinson’s, given one of four possible doses over the course of a year. Evaluations found no serious treatment-related adverse side effects and no immune reactions to the cells, which came from healthy donor bone marrow.

Although safety was the study’s main goal, investigators also reported observing a reduction in motor symptoms and markers of inflammation.

“To our knowledge, this is the first study to demonstrate that a single intravenous infusion of [donor-derived mesenchymal stem cells] is safe, well tolerated, and not immunogenic … in subjects with mild to moderate PD [Parkinson’s disease],” the researchers wrote.

The enrolling Phase 2 trial (NCT04506073) aims to identify the safest and most effective number of stem cell infusions needed to slow disease progression, as measured by Part III of the Movement Disorder Society Unified Parkinson’s Disease Rating Scale, compared to placebo infusions. Among requirements for eligible patients is the need to be within three to 10 years of a diagnosis, and evidence of slowed, difficult movement (bradykinesia).

Participants will receive two to three infusions every three months, with periodic follow-ups over the course of a year.

Secondary trial goals include assessments of safety and tolerability, motor function, and quality-of-life measures.

“By investigating a treatment that can slow or stop the progression, we hope to improve the quality of life of those suffering from the disease,” Schiess said.

“The ultimate goal is to use this treatment in individuals with a prodromal condition, meaning they are showing early signs of Parkinson’s disease but are not yet clinically symptomatic,” she added. “We hope to be able to potentially stop the disease’s conversion or clinical manifestation in patients who are high-risk.”

The Michael J. Fox Foundation, John S. Dunn Foundation, and John and Kyle Kirksey are helping to fund the trial.