What SS-31 is
SS-31 is the research name for elamipretide, a Szeto-Schiller peptide that concentrates in the inner mitochondrial membrane and binds cardiolipin, developed by Stealth BioTherapeutics through real Phase 2 and 3 trials in mitochondrial myopathy, Barth syndrome, and eye disease. It is a legitimate investigational drug with published human pharmacokinetics, which is rare for compounds in the longevity corner of the gray market.
Worth knowing: the clinical trials dosed 40 mg daily, several times the common community dose, so gray-market protocols are running well below the exposure the trial evidence describes.
What we do not know
- The Phase 3 trial in primary mitochondrial myopathy did not meet its primary endpoint. That is a published negative result, not an absence of data.
- Not approved for any indication.
- The Barth syndrome evidence is small by necessity, given how rare the condition is.
- General anti-aging or performance use is not what any trial studied.
Reconstitution math
Concentration is everything: the same 10 mg vial gives a different draw for every amount of bacteriostatic water you add. The table uses the common 2 mL setup for each vial size, which puts every unit on a U-100 insulin syringe at 50 mcg for the default vial. Dashes mark draws too small to measure or larger than the syringe.
| Vial | BAC water | Concentration | 5 mg | 10 mg |
|---|---|---|---|---|
| 10 mg | 2 mL | 5 mg/mL | 100 u | - |
| 50 mg | 2 mL | 25 mg/mL | 20 u | 40 u |
Dosing and protocol
Clinical trials dosed 40 mg daily subcutaneously; community protocols run 5 to 10 mg daily.
Community protocols run 5 to 10 mg subcutaneously daily, usually in the morning. On a 10 mg vial with 2 mL of water, 5 mg is a 50-unit draw. With a half-life of a few hours there is no accumulation; daily dosing is about repeated exposure, not building a level.
Pharmacokinetics
SS-31 has published human pharmacokinetics: peak about one hour after a subcutaneous dose; half-life in the 2 to 4 hour range. The curves below are normalized one-compartment models built from the cited half-life, the same math the Planner uses. They show shape and timing, not absolute blood levels.
How it is thought to work
Elamipretide is a mitochondria-targeted tetrapeptide that binds cardiolipin in the inner mitochondrial membrane, stabilizing cristae structure and improving electron transport efficiency. It is the most conventionally developed compound in this group, with registered Phase 3 trials.
What the evidence supports
This table grades how well each outcome has been studied in humans, not how well SS-31 works. A strong grade means the question was asked properly, and the answer may still have been negative. Nothing here is inherited from a drug class, a close analog, or the parent molecule of a fragment.
| Outcome | Strongest published evidence |
|---|---|
| Barth syndrome | Human RCT |
| Dry age-related macular degeneration | Human RCT |
| Primary mitochondrial myopathy | Human RCT |
| Anti-aging or performance in healthy people | No data |
Storage and handling
Lyophilized vials keep best cold, dark, and dry; refrigeration is the community default and freezing lyophilized powder is common for long holds. After reconstitution, refrigerate at 2 to 8 C, do not freeze the solution, and date the vial. Bacteriostatic water's preservative keeps multi-dose use practical for about 28 days by USP convention, though our 120-day stability study found the preservative itself outlasts that window.
Got a certificate of analysis with your vial? Run it through our COA Reader: it reads the report in plain English, checks purity and mass against the label claim, and links the testing lab’s own verification page. Our guide to reading a COA explains what the numbers do and do not tell you.
Sources
- Karaa et al., Elamipretide in mitochondrial myopathy (MMPOWER-3), Neurology 2023
- Reid Thompson et al., Elamipretide in Barth syndrome (TAZPOWER), Genet Med 2021