Review · United States
SS-31
Reviewed on
Approval and product status
Forzinity has FDA accelerated approval for a narrow Barth syndrome use
FDA maps SS-31 to elamipretide, but the approval is for the specific Forzinity product and a narrow use. An online product labeled SS-31 or elamipretide is not automatically the same product as Forzinity.
What was measured in people?
- Health results · Moderate
- FDA approval covers one rare disease and one muscle-strength measure. Results in other conditions have been mixed, including a negative phase 3 study.
- Body changes · Strong
- The FDA label describes elamipretide's four-amino-acid sequence and its binding to cardiolipin inside mitochondria.
A change in a hormone or body signal does not by itself prove a health benefit.
Important limits
This tool is not an independent medical review. It does not recommend treatment.
The Forzinity label warns about serious allergic reactions and injection-site reactions. Those warnings apply to the approved product and do not prove that another SS-31 product is the same. This guide gives no dosing, injection, sourcing, product-use, treatment, or performance advice.
Still unknown: One small study in healthy older adults measured how well muscle mitochondria made energy. It did not establish more daily energy, less fatigue, longer life, or slower aging. Results in Barth syndrome do not transfer to healthy people or other diseases. FDA approval names the controlled Forzinity product. It does not show that an online SS-31 vial has the same formulation, quality controls, or evidence.
This record cannot check a package, seller, batch, or personal treatment. It does not provide sport clearance.
Approval fact checks
“Forzinity is FDA-approved for a narrow Barth syndrome use.”
Supported with scope. FDA granted accelerated approval for Forzinity to improve muscle strength in adults and children with Barth syndrome who weigh at least 30 kg. Accelerated approval uses an intermediate measure and requires a confirmatory study.
Applies to: The Forzinity label and FDA approval records as reviewed August 30, 2026.
Products in this review
These are selected records, not every product or form.
Forzinity
- Ingredients and form
- Injection
- How it enters the body
- Under the skin (subcutaneous)
- Use and people covered
- To improve muscle strength in adults and children with Barth syndrome who weigh at least 30 kg.
Published label: September 2025
Read the published Forzinity FDA label (PDF)What the research shows
FDA granted Forzinity accelerated approval for adults and children with Barth syndrome who weigh at least 30 kg. The main study included 12 males age 12 or older at one U.S. site. In the randomized part, Forzinity did not beat placebo for walking distance or fatigue. FDA relied on knee-muscle strength measured during a later open-label extension, when everyone knew they received Forzinity. FDA requires another randomized study to confirm a patient benefit. In a separate 24-week study, 218 people with primary mitochondrial myopathy did not have better walking distance or fatigue with elamipretide than with placebo.
Read all SS-31 fact checksSources used in this review
A source may support some statements, not all of them. Use the links above or this review to see what each source supports.
Show 11 sources
- FDA identity record for elamipretide and SS-31
U.S. Food and Drug Administration · Reference · 2026
Source accessed
- FDA grants accelerated approval to Forzinity for Barth syndrome
U.S. Food and Drug Administration · Regulatory · 2025
Source accessed
- Forzinity Drug Trials Snapshot
U.S. Food and Drug Administration · FDA review · 2025
Source accessed
- Forzinity prescribing information
U.S. Food and Drug Administration · Drug label · 2025
Source accessed
- Forzinity FDA approval letter
U.S. Food and Drug Administration · Regulatory · 2025
Source accessed
- TAZPOWER randomized Barth syndrome study
PubMed · Randomized trial · 2020
Source accessed
- MMPOWER-3 phase 3 mitochondrial-myopathy study
PubMed · Randomized trial · 2023
Source accessed
- MMPOWER-2 mitochondrial-myopathy study
PubMed · Randomized trial · 2020
Source accessed
- PROGRESS-HF elamipretide heart-failure study
PubMed · Randomized trial · 2020
Source accessed
- Elamipretide study in healthy older adults
PubMed · Human pilot · 2021
Source accessed
- TAZPOWER clinical study record
ClinicalTrials.gov · Trial registry · 2017
Source accessed