Mitochondrial

Elamipretide

SS-31; MTP-131; Forzinity

US status
FDA-approved
Class
Mitochondrial
Approved product
Forzinity (2025)
Route
Subcutaneous injection, once daily

By Diane Walker · Reference Editor · Reviewed September 2026

Regulatory record

3 dated actions on record.
September 2025
FDA approves elamipretide injection under new drug application 215244, approval dated September 19, 2025, as a Type 1 new molecular entity. Drugs@FDA records the product as Forzinity, a subcutaneous solution of elamipretide hydrochloride at 280 mg base per 3.5 mL, sponsored by Stealth BioTherapeutics and marketed as prescription-only.
December 2025
The label in effect December 10, 2025 indicates the product to improve muscle strength in adult and pediatric patients with Barth syndrome weighing at least 30 kg. The same section states that the indication is approved under accelerated approval on an improvement in knee extensor muscle strength, an intermediate clinical endpoint, and that continued approval may be contingent upon verification of clinical benefit in a confirmatory trial.
September 2026
Elamipretide appears in none of the three categories of the 503A bulks list published May 14, 2026; that list files substances nominated for compounding, and a marketed product supplies this one. FDA's drug shortage database holds no entry for it.

Every entry above is dated; the record is current as of the review date.

Definition

Elamipretide is a synthetic tetrapeptide that concentrates in the inner mitochondrial membrane and binds cardiolipin, the phospholipid whose remodeling fails in Barth syndrome; the label gives its sequence as D-Arg-2,6-dimethyl-Tyr-Lys-Phe-NH2 and calls the product a mitochondrial cardiolipin binder [1].

It reaches this index through the company it keeps rather than through any market of its own. Providers who sell NAD+ and list MOTS-c as a mitochondrial peptide are describing a category whose only approved member is this one, and that member's label names a single rare genetic disorder.

Evidence

Across five name variants PubMed returns 470 indexed records, of which 201 carry the Humans subject heading, 22 the clinical-trial publication type and 19 the randomized-controlled-trial type [2]. All twenty-two were opened and read; eighteen name a variant, four are matches on the search rather than on the compound, and one of the eighteen is a rat study that carries a trial publication type anyway [2].

The approved indication rests on a program of about a dozen participants. TAZPOWER randomized twelve subjects to elamipretide or placebo in a twelve-week crossover and neither primary endpoint was met; ten continued into an open-label extension, where the six-minute walk distance improved by 95.9 meters at 36 weeks at a p value of 0.024 [3]. The 168-week extension reported sustained tolerability and a cumulative 96.1 meter improvement at week 168, at a p value of 0.003, in the eight patients who reached that visit [4].

The largest controlled trial of the compound failed, and it failed in a different disease. MMPOWER-3 randomized 218 adults with genetically confirmed primary mitochondrial myopathy and met neither primary endpoint, with a six-minute walk difference of minus 3.2 meters at a p value of 0.69 [5].

Two further randomized trials sit outside the approved indication and neither produced one: a placebo-controlled trial in heart failure [6], and a trial of a topical ophthalmic solution in Leber hereditary optic neuropathy, which is not even the approved route [7]. A reader meeting the word mitochondrial on a provider menu is meeting a compound whose record is a rare-disease program with one positive extension and one negative phase 3.

Lawful access

The lawful supply route is the approved product. FDA approved elamipretide injection under new drug application 215244 on September 19, 2025 as a Type 1 new molecular entity, and Drugs@FDA records Forzinity as a subcutaneous solution of elamipretide hydrochloride at 280 mg base per 3.5 mL, sponsored by Stealth BioTherapeutics and marketed as prescription-only [8].

The label states the indication and the condition attached to it in the same breath. In the version effective December 10, 2025 the product is indicated "to improve muscle strength in adult and pediatric patients with Barth syndrome weighing at least 30 kg", and that indication "is approved under accelerated approval based on an improvement in knee extensor muscle strength, an intermediate clinical endpoint", with continued approval that "may be contingent upon verification and description of clinical benefit in a confirmatory trial" [1].

Compounding does not arise for this molecule. Elamipretide appears in none of the three categories of the section 503A bulks list published May 14, 2026 [9], and FDA's drug shortage database holds no entry for it [10]. No supplier is listed here, and the rail is empty because no approved program on this profile has been verified as offering it.

Elsewhere in this index

Filed under

Reference tables

Same class

References

  1. FORZINITY (elamipretide) injection, prescribing information, structured product label version 10, effective December 10, 2025. Sections 1 Indications and Usage and 11 Description. Read 2026-09-02 through the openFDA label endpoint; the cited repository page resolves to 174,849 bytes naming FORZINITY 136 times, in a run whose nonsense-path control on the same host resolved to 75,120 bytes naming it none. Source
  2. PubMed, National Library of Medicine. Census run 2026-09-02 across five name variants — "elamipretide" OR "SS-31" OR "MTP-131" OR "Bendavia" OR "Forzinity" — returning 470 indexed records, 201 carrying the Humans MeSH term, 22 under "clinical trial"[Publication Type] and 19 under "randomized controlled trial"[Publication Type]. All 22 trial-type records were retrieved and read individually rather than counted: 18 name a variant in the title or abstract, and 4 do not and are artifacts of the search — a metoclopramide pharmacokinetic comparison, a water-based resistance training study, an aficamten trial in hypertrophic cardiomyopathy, and a 1977 report on pancreatic duct antibodies. One of the 18, a 2007 rat myocardial-infarction study, carries a trial publication type despite being an animal study. The publication-type filter was proved live in the same run against a control term returning 8,907 records under the clinical-trial type and 6,116 under the randomized type; the invalid tag clinicaltrial[pt] returned 0 for that control term in the same run, and a deliberately invalid record identifier errored in the same run. Source
  3. 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, a genetic disorder of mitochondrial cardiolipin metabolism. Genet Med. 2021;23(3):471–478. PMID 33077895
  4. Thompson WR, Manuel R, Abbruscato A, et al. Long-term efficacy and safety of elamipretide in patients with Barth syndrome: 168-week open-label extension results of TAZPOWER. Genet Med. 2024;26(7):101138. PMID 38602181
  5. Karaa A, Bertini E, Carelli V, et al. Efficacy and Safety of Elamipretide in Individuals With Primary Mitochondrial Myopathy: The MMPOWER-3 Randomized Clinical Trial. Neurology. 2023;101(3):e238–e252. PMID 37268435
  6. Daubert MA, Yow E, Dunn G, et al. Novel Mitochondria-Targeting Peptide in Heart Failure Treatment: A Randomized, Placebo-Controlled Trial of Elamipretide. Circ Heart Fail. 2017;10(12). PMID 29217757
  7. Karanjia R, Sadun AA. Elamipretide Topical Ophthalmic Solution for the Treatment of Subjects with Leber Hereditary Optic Neuropathy: A Randomized Trial. Ophthalmology. 2024;131(4):422–433. PMID 37923251
  8. Drugs@FDA, US Food and Drug Administration. Application NDA 215244, FORZINITY (elamipretide hydrochloride), sponsor Stealth BioTherapeutics; subcutaneous solution, EQ 280MG BASE/3.5ML, marketing status Prescription, original approval dated September 19, 2025, submission class Type 1 - New Molecular Entity, with no supplements recorded. Read 2026-09-02 through the openFDA drugsfda endpoint, in a run whose control query on a nonexistent ingredient returned no match; the cited overview page resolves to 31,285 bytes naming FORZINITY, while a nonexistent application number on the same host resolves to 19,938 bytes naming nothing. Source
  9. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act, US Food and Drug Administration, face date "Updated May 14, 2026". Read 2026-09-02. Elamipretide appears in none of the three categories; the document was extracted in full and searched under the name and its code names, in a run whose positive control terms — nicotinamide adenine dinucleotide, secretin and L-carnosine, each already recorded in this index — all appeared, and whose nonsense control term did not. A nonexistent document identifier on the same host returned 404 in the same run. Source
  10. FDA Drug Shortages database, US Food and Drug Administration. Queried 2026-09-02 through the openFDA shortages endpoint: no record for elamipretide. The query was controlled in the same run against liraglutide, which returned 11 records with the status Current, and semaglutide, which returned 3. Source

The editor is not a licensed clinician; this monograph is a regulatory and evidence reference, not medical advice. Statuses are re-verified on the date shown, and every quantitative claim resolves to a numbered reference. Corrections: editor@peptideamerica.org. See how this reference is funded.