Elamipretide is a mitochondrial cardiolipin-binding drug designed to support the structures cells use to make energy.
What Elamipretide does and why that matters
Elamipretide is designed to bind cardiolipin, a fat-like component of the inner mitochondrial membrane, and support the structures cells use to make energy. For people with Barth syndrome, the approved practical goal is stronger muscles for everyday movement. The approval is not evidence that elamipretide improves general fatigue, athletic performance or aging in people without that rare disease. [1,2,3,4,5]
Function evidence: Approved Barth syndrome use; broader energy and longevity claims unproven
What the approved benefit means in daily life
For a person with Barth syndrome who meets the label criteria, stronger muscles can matter for ordinary movement and physical tasks. That disease-specific goal is the basis of Forzinity's accelerated approval, with continued approval potentially depending on confirmation of benefit. It is not evidence that someone without Barth syndrome will feel more energetic, exercise longer or slow aging. Studies in other mitochondrial conditions have produced mixed results or missed primary endpoints, so the broader wellness story remains separate from the approved use. [1,2,3,4,5]
What supports this description: Accelerated approval for Barth syndrome; broader performance claims unsupported
Elamipretide Dosing status
Dose: 40 mg for labeled patients weighing at least 30 kg | Frequency: Subcutaneous injection once daily at the same time each day | Cycle: Ongoing prescription treatment; no labeled cycling schedule | Route: Subcutaneous
Preparation: None for Forzinity; supplied as an 80 mg/mL ready-to-use solution.
The FDA label reduces the adult dose to 20 mg once daily when eGFR is below 30 mL/min and the patient is not on dialysis. There is insufficient information for adults on dialysis or for pediatric patients with renal impairment. Dose selection belongs to the prescriber. [1]
Elamipretide Effects
Muscle strength in Barth syndrome. The approved indication is improvement of muscle strength in patients with Barth syndrome weighing at least 30 kg. Continued approval may depend on a confirmatory trial. [1]
Mitochondrial cardiolipin binding. FDA labeling classifies elamipretide as a mitochondrial cardiolipin binder. Mechanistic plausibility does not by itself demonstrate a clinical benefit in other conditions. [1]
Evidence outside the indication. Trials in primary mitochondrial myopathy and other groups have reported mixed results or missed their primary endpoints. FDA approval for Barth syndrome does not show that the drug improves general wellness or longevity. [3,4,5]
Elamipretide Side Effects
Injection-site reactions. In the 12-patient placebo-controlled crossover study, local administration reactions were common, including erythema, pain, induration, itching, bruising and urticaria. [1]
Hypersensitivity. Serious allergic reactions requiring emergency treatment have been reported. The FDA label instructs patients to stop treatment and seek immediate care for a serious reaction. [1]
Benzyl alcohol risk. Forzinity contains benzyl alcohol and is not approved for neonates because benzyl alcohol can cause severe toxicity in that population. [1]
Eosinophilia. Increased eosinophil counts were frequently observed in studies lasting at least 30 days, generally without associated clinical manifestations. [1]
Elamipretide Dosing by Use Case
Condition
Dose
Duration
Notes
Barth syndrome in a patient weighing at least 30 kg
40 mg subcutaneously once daily
As prescribed
This is the FDA-approved use. Adults with severe renal impairment who are not on dialysis have a labeled 20 mg once-daily dose. [1]
Frequently Asked Questions About Elamipretide
What is elamipretide?
Elamipretide is a mitochondrial cardiolipin binder. The FDA-approved product is Forzinity, a prescription subcutaneous injection for certain patients with Barth syndrome. SS-31 is a research name used in the literature. [1]
What is Forzinity approved to treat?
It is approved to improve muscle strength in adults and children with Barth syndrome who weigh at least 30 kg. It is not approved for longevity, anti-aging, general fatigue, exercise enhancement or other mitochondrial disorders. [1]
What is the FDA-approved dose?
For patients weighing at least 30 kg, the labeled dose is 40 mg subcutaneously once daily at the same time each day. The label specifies a lower adult dose for severe renal impairment when the patient is not on dialysis. [1]
Does Forzinity need to be reconstituted?
No. The approved product is supplied as a ready-to-use 80 mg/mL solution in a 280 mg/3.5 mL single-patient-use vial. Directions for an unapproved lyophilized vial are not Forzinity instructions. [1]
What are the main safety issues?
Injection-site reactions were very common in the small Barth syndrome trial. Serious hypersensitivity reactions have occurred. The product contains benzyl alcohol and is not approved for neonates. It is contraindicated after serious hypersensitivity to elamipretide or an ingredient. [1]
Does FDA approval prove elamipretide works for longevity?
No. The approval applies to a defined Barth syndrome population and an intermediate muscle-strength endpoint. It does not validate unapproved doses or claims for healthy people. [1]
Evidence
FDA accelerated approval for a narrow indication. Forzinity received accelerated approval in 2025 to improve muscle strength in adults and children with Barth syndrome who weigh at least 30 kg. Approval was based on an intermediate endpoint and may depend on confirmation of clinical benefit. This approval does not establish efficacy for aging, fatigue, athletic performance or general mitochondrial health. [1,2]
Approval status: FDA accelerated approval for Barth syndrome in patients weighing at least 30 kg
References
U.S. Food and Drug Administration Forzinity (elamipretide) prescribing information FDA-approved labeling, 2025. Source
U.S. Food and Drug Administration FDA Grants Accelerated Approval to First Treatment for Barth Syndrome FDA news release, 2025. Source
Reid Thompson W, Hornby B, Manuel R, et al. A phase 2/3 randomized clinical trial followed by an open-label extension to evaluate the effectiveness of elamipretide in Barth syndrome. Genetics in Medicine, 2021. PMID 33077895
Karaa A, Haas R, Goldstein A, et al. Efficacy and Safety of Elamipretide in Individuals With Primary Mitochondrial Myopathy: The MMPOWER-3 Randomized Clinical Trial. Neurology, 2023. PMID 37268435
Roshanravan B, Liu SZ, Ali AS, et al. In vivo mitochondrial ATP production is improved in older adult skeletal muscle after a single dose of elamipretide in a randomized trial. PLOS ONE, 2021. PMID 34264994
Storage
Unopened Forzinity vial: Refrigerate at 2°C to 8°C (36°F to 46°F). Do not freeze. [1]
After first opening: Store refrigerated at 2°C to 8°C or at room temperature from 20°C to 25°C. Discard eight days after first opening. [1]
Product appearance: The labeled product is a clear, colorless-to-yellow solution. Do not use it if cloudy or if particles are present. [1]
Educational evidence summary. Approval applies only to the named product and indication; compounded, investigational, and research-market products are different categories.
◇An FDA-approved label or a patient-specific prescription from a licensed pharmacy
◇The active ingredient, strength, dosage form, concentration, lot, and dispensing instructions
◇Identity or purity tests only support the tests performed; they do not prove sterility, endotoxin safety, dose accuracy, stability, or clinical suitability
◇A “research use only” vial is not a patient medicine
