The SS 31 dosing protocol used in human trials is typically 40 mg subcutaneously once daily. Learn how elamipretide dosing works, what studies show, and safety.
SS-31 (elamipretide) has no FDA-approved dosing protocol, because it remains an investigational peptide in the United States. In published human trials, the dominant schedule has been 40 mg given as a single subcutaneous injection once daily. Earlier cardiac studies instead used intravenous infusions measured in milligrams per kilogram per hour. Anyone weighing personal use should treat those numbers as research findings rather than medical advice and review them with a licensed clinician.
What SS-31 (Elamipretide) Actually Is
SS-31 is a synthetic tetrapeptide, D-Arg-Dmt-Lys-Phe-NH2, designed to accumulate in the inner mitochondrial membrane and bind cardiolipin, a phospholipid tied to cellular energy production. Stealth BioTherapeutics develops it under the generic name elamipretide.
Researchers have studied the peptide in Barth syndrome, primary mitochondrial myopathy, heart failure, and dry age-related macular degeneration. Because those programs are still experimental, no official ss-31 dosing protocol exists outside of a clinical trial protocol.
SS-31 is often discussed alongside other mitochondrial research compounds. People frequently ask about ss-31 and mots-c together, even though no human trial has tested the two as a stack, and no published data supports combining them.
Dosing Used in Published Human Trials
Human research has converged on a small number of schedules. The table below summarizes the doses most often cited in peer-reviewed literature and trial registries.
| Program | Population | Route | Dose | Schedule |
|---|---|---|---|---|
| TAZPOWER | Barth syndrome | Subcutaneous | 40 mg | Once daily |
| MMPOWER-2 and MMPOWER-3 | Primary mitochondrial myopathy | Subcutaneous | 40 mg | Once daily |
| ReCLAIM and ReCLAIM-2 | Dry age-related macular degeneration | Subcutaneous | 40 mg | Once daily |
| Cardiac infusion studies | Heart attack and heart failure | Intravenous | Roughly 0.05 to 0.25 mg/kg per hour | Infusion over several hours |
| Preclinical rodent work | Laboratory models | Subcutaneous or intraperitoneal | 1 to 5 mg/kg | Daily |
Across the subcutaneous trials, ss-31 peptide dosing has stayed remarkably consistent: one injection, once per day, with no loading dose. The 40 mg figure appears in nearly every human study that reached mid- or late-stage testing.
Why 40 mg Subcutaneously Became the Research Standard
- Convenience: a single daily injection is easy to standardize across many trial sites and patients.
- Exposure profile: subcutaneous absorption produces a gradual rise in plasma levels rather than the sharp spike of a rapid bolus.
- Consistency: one fixed milligram dose removes weight-based calculations and simplifies trial design.
- Precedent: once one program established 40 mg, later studies matched that number so results could be compared directly.
Fixed dosing has a tradeoff. A 45 kg patient and a 110 kg patient receive the same amount, which is one reason cardiac researchers dosed by body weight during intravenous infusion instead.
Half-Life, Timing, and Route of Administration
Elamipretide clears quickly. Reported plasma half-lives cluster around two to four hours after subcutaneous administration, which is why researchers chose once-daily injections instead of splitting the dose.
A short half-life also means blood levels fall well below peak for much of the day. Trials that needed continuous exposure used intravenous infusion rather than injections. No published human study has compared once-daily subcutaneous dosing with twice-daily dosing head to head, and healthy adults have not been the focus of these trials.
Reported Side Effects and Safety Signals
Safety data come from trial participants, most of whom had a serious underlying disease. That context matters when reading any summary of ss-31 peptide side effects.
- Injection site reactions such as pain, redness, swelling, itching, and bruising, which are the most frequently reported events.
- Headache, nausea, dizziness, and fatigue.
- Occasional reports of back pain, diarrhea, and blood pressure changes.
MMPOWER-3, the largest primary mitochondrial myopathy trial, did not meet its primary six-minute walk endpoint, so the evidence for meaningful functional benefit in that population is mixed. SS-31 is not FDA-approved for human use in the United States, and long-term safety in otherwise healthy adults has not been established.
Purity, Sourcing, and What Labels Do Not Tell You
Research peptides sold online are not held to pharmaceutical manufacturing standards. A purity percentage printed on a label means little without an independent certificate of analysis that matches the specific batch being shipped.
Retail write-ups such as the ss-31 peptide dosage swolverine guide often repeat the 40 mg trial figure without explaining the study population or the difference between research use and clinical care. Buyers comparing vendors should weigh third-party testing, cold-chain shipping, and documentation far above price per vial.
Anyone who decides to ss-31 peptide buy online should assume the product is a research chemical rather than a finished drug, and should recognize that dosing errors become more likely when concentration is unverified.
Balancing Research Interest With Medical Advice
Mitochondrial biology is an active field, and elamipretide remains one of its most studied peptides. Enthusiasm for the mechanism, however, does not substitute for regulatory review or completed clinical evidence.
People with diagnosed mitochondrial disease, heart failure, or vision loss should discuss any interest in SS-31 with the specialist managing their care. A clinician can explain trial eligibility, approved alternatives, and the monitoring that a self-directed protocol would skip.
Frequently Asked Questions
What is the typical SS-31 dosing protocol used in human studies?
Most published human trials have used 40 mg of elamipretide injected subcutaneously once daily, with no loading dose. Earlier cardiac studies instead delivered intravenous infusions dosed by body weight, roughly 0.05 to 0.25 mg/kg per hour. No official protocol exists because the peptide is still investigational.
Is SS-31 approved by the FDA?
No. SS-31, also called elamipretide, is not FDA-approved for any human indication in the United States. It is available online only as a research chemical, which means it has not passed the safety, purity, and manufacturing reviews required for prescription drugs.
How long does SS-31 stay in your system?
Reported plasma half-lives for elamipretide are roughly two to four hours after subcutaneous injection, so most of the dose clears within a day. That short half-life is the main reason trials used once-daily dosing rather than splitting the amount into multiple smaller injections.
This page provides educational research information and does not replace medical advice, diagnosis, or treatment.