Enrollment Completed for Phase 2/3 Trial of Elamipretide for Treatment of Barth Syndrome

Enrollment has been completed for a Phase 2/3 trial to evaluate the safety, effectiveness, and tolerability of investigational therapy elamipretide in patients with Barth Syndrome, a rare mitochondrial disorder, Stealth BioTherapeutics announced. 

In July 2017, the company launched the randomized trial, called TAZPOWER (NCT03098797), to evaluate the effects of daily subcutaneous injections of elamipretide in 12 patients with genetically confirmed Barth syndrome.  

The primary objective, assessed at week 12, is the change in distance walked by patients during the six-minute walk test. Additional endpoints will assess muscle strength, heart performance, patient-reported outcomes, and adverse effects.

Barth syndrome is estimated to affect one in 200,000 to 400,000 individuals worldwide at birth, exclusively males. It causes muscle weakness, heart problems, recurrent infections due to low white blood cell count, and delayed growth.

The condition is hereditary, caused by mutations in the TAZ gene, which is important for energy-making activities in the mitochondria, the power-producing centers of cells.

There are currently no approved therapies for Barth syndrome. But last November the U.S. Food and Drug Administration (FDA) granted Stealth fast track designation for elamipretide in the treatment of the disease.

Elamipretide is Stealth’s lead product candidate, with the potential to restore normal energy production in damaged mitochondria and reduce oxidative stress. 

Based on preclinical and early clinical data, the company believes there is strong rationale for the ability of elamipretide to treat diseases caused by mitochondrial dysfunction.

The company is investigating elamipretide for two other mitochondrial diseases — primary mitochondrial myopathy, for which it received orphan drug status, and Leber’s Hereditary Optic Neuropathy — as well as in dry age-related macular degeneration.

Results from the TAZPOWER trial are expected to be announced at the end of 2018.

“We are grateful for the support we have received from the Barth community in recruiting an estimated 10 percent of the U.S. adult Barth population to participate in this trial,” Reenie McCarthy, Stealth’s CEO, said in a press release.

“We are eager to understand the therapeutic potential of elamipretide to treat this ultra-rare disease, and remain on track to announce top-line results later this year,” she said.

Stealth is a biotechnology company focused on the development of treatments for diseases related to mitochondrial dysfunction.