Peptide that concentrates in the inner mitochondrial membrane. Approved in the US to improve muscle strength in Barth syndrome, a very rare genetic disease.
FDA (US): Accelerated approval (September 2025, Forzinity) to improve muscle strength in patients with Barth syndrome weighing at least 30 kg; full approval depends on a confirmatory trial.
EMA (EU): Not approved.
Dose
40 mg subcutaneously once daily in patients ≥30 kg; 20 mg/day if glomerular filtration rate is <30 ml/min without dialysis (FDA 2025 prescribing information).
Safety
Very common injection-site reactions (redness, pain, induration, itching). Increased eosinophils with prolonged use and cases of severe hypersensitivity. Do not use in neonates (contains benzyl alcohol). No data in pregnancy. Use only with a specialist prescription.
Differences between women and men
Barth syndrome, its only approved indication, is an X-linked disease that affects almost exclusively males; female carriers do not usually manifest it. View the study →
Effect by goal · level of evidence
Walking capacity in Barth syndrome
improvesLow-moderateclinical trial (A)in people
+96 m in 6MWT
Open-label extension of the TAZPOWER trial (10 patients, 8 reached week 168) with 40 mg/day: distance on the 6-minute walk test improved cumulatively by 96 meters. In the earlier randomized phase (12 patients) the primary endpoints were not met.
24-week phase 3 MMPOWER-3 trial: elamipretide did not improve the 6-minute walk test or fatigue versus placebo in adults with primary mitochondrial myopathy.
Binds to cardiolipin, a key lipid of the inner mitochondrial membrane. In doing so it stabilizes the respiratory chain and improves energy production, reducing the formation of free radicals. In Barth syndrome, cardiolipin is abnormal because of a defect in the TAFAZZIN gene.
What the evidence says
In people
Walking capacity in Barth syndrome. Open-label extension of the TAZPOWER trial (10 patients, 8 reached week 168) at 40 mg/day: the distance in the 6-minute walk test improved by a cumulative 96 meters. In the earlier randomized phase (12 patients), the primary endpoints were not met. PubMed 38602181
Primary mitochondrial myopathy. 24-week phase 3 MMPOWER-3 trial: elamipretide did not improve the 6-minute walk test or fatigue compared with placebo in adults with primary mitochondrial myopathy. PubMed 37268435