FDA to Review Barth Syndrome Treatment Elamipretide

The Food and Drug Administration (FDA) has accepted the New Drug Application (NDA) for elamipretide for the treatment of Barth syndrome.

Barth syndrome is a rare genetic disorder characterized by muscle weakness and heart abnormalities, often resulting in heart failure, recurrent infections, delayed growth, and reduced life expectancy. Elamipretide is a peptide compound designed to penetrate cell membranes targeting the inner mitochondrial membrane where it binds reversibly to cardiolipin.

The application for elamipretide is supported by data from the SPIBA-001 phase 3 retrospective natural history control trial, which compared data from the open-label portion of the TAZPOWER phase 2/3 study (ClinicalTrials.gov Identifier: NCT03098797) to matched natural history controls. Findings showed treatment with elamipretide met the primary and most secondary endpoints demonstrating improvements in assessments of exercise tolerance, strength, and cardiac function.

Additionally, the effectiveness of elamipretide was supported by data from the TAZPOWER study in 12 male patients 12 years of age and older with genetically-confirmed Barth syndrome. Study participants were randomly assigned to receive elamipretide 40mg subcutaneously once daily for 12 weeks or placebo (part 1), followed by a 4-week washout and then 12 weeks in the opposite arm. In the open-label extension phase (part 2), 10 patients received elamipretide 40mg daily, of which 8 patients reached 36 weeks of treatment.

Results from part 2 showed treatment with elamipretide demonstrated significant improvements in the 6-minute walk test (primary endpoint; +95.9 m; P =.024) and the Barth Syndrome Symptom Assessment scale (-2.1 points; P =.031). Moreover, significant improvements were observed in knee extensor strength, patient global impression of symptoms, and certain cardiac parameters.

“We are pleased that the FDA has not only filed our NDA for Barth syndrome but has also committed to a transparent review process with its decision to convene an advisory committee,” said Reenie McCarthy, Chief Executive Officer. “We welcome the input of committee experts to advise FDA on the seriousness of this devastating disease and the urgency of the unmet need, including in light of FDA’s puzzling review designation.  We look forward to working with the FDA through the review process.”