A new trial may have pinpointed the first treatment that provides meaningful functional improvements in the most advanced cases of Duchenne muscular dystrophy (DMD). Researchers at UC Davis Health and six other sites showed that a cellular therapy appears to be safe and effective in stopping the deterioration of upper limb and heart functions. The trial used Capricor Therapeutics’ CAP-1002 allogeneic cardiosphere-derived cells (CDCs).
“HOPE-2 is the first clinical trial to test systemic cell therapy in DMD,” said Craig McDonald, the trial’s national principal investigator and lead author on the study. McDonald is the professor and chair of physical medicine and rehabilitation at UC Davis Health. “The trial produced statistically significant and unprecedented stabilization of both skeletal muscle deterioration affecting the arms and heart deterioration of structure and function in non-ambulatory DMD patients.”
Findings from the trial were published this week in The Lancet.
DMD is a disorder that affects about one in 5,000 people—mostly boys. It usually becomes apparent in early childhood, causing progressive weakness and chronic inflammation of the skeletal, heart, and respiratory muscles. Treatments for DMD are limited and there is no known cure.
Capricor Therapeutics’ CDCs are obtained from human heart muscles. The company says these cells can reduce muscle inflammation and enhance cell regeneration.
“The primary mechanism of the CAP-1002 therapy is to help reduce the disease’s serious chronic inflammation problems, decrease fibrosis and improve muscle regeneration, and thereby maintain or improve critical heart and skeletal muscle function,” McDonald said.
The trial examined the long-term efficacy and safety of repeated intravenous infusions of CAP-1002 for the treatment of late-stage DMD. It enrolled 20 patients with DMD at seven U.S. centers. The participants were at least 10 years old with moderate weakness in their arms and hands. They were randomly assigned to receive either CAP-1002 or a placebo every three months for one year, with a total of four infusions.
The team assessed upper limb function using the Performance of Upper Limb (PUL) motor function scale, heart function, spirometry measures of respiratory function, and circulating biomarkers.
PUL was accessed after the first infusion and after one year. The study found a significant favorable change in participants who received CAP-1002, compared to those who got the placebo. The researchers reported far less deterioration of upper extremity muscle function in the cell-treated group. Cardiac MRI also showed that the heart structure and function seemed to improve in participants who received CAP-1002.
“Here we show the promise of cell therapy in preventing the progression of heart disease in a rare genetic disease, but there is good reason to believe that such therapy may one day also be used for more common forms of heart failure,” said co-author Eduardo Marbán, who first discovered that CDCs might be useful in treating DMD. He is the Mark Siegel Family Foundation Distinguished Professor and executive director of the Smidt Heart Institute of the Cedars-Sinai Medical Center in Los Angeles.
McDonald and collaborators in other centers in the United States are launching a Phase III clinical trial, HOPE-3. The goal of this study is to confirm the efficacy of CAP-1002 in a larger cohort of patients.
“The FDA has signaled that a larger Phase III study would be the next step toward gaining drug approval. We need to confirm therapeutic durability and safety of CAP-1002 beyond 12 months for the treatment of muscular degeneration in the heart and skeleton,” McDonald said.