⚠ Educational reference only — not medical advice.** This article is for research and educational reference. Always consult your own physician before considering any peptide protocol. See the full Disclaimer at the end of this article.

Introduction
SS-31 (elamipretide, MTP-131) is an aromatic-cationic tetrapeptide developed by Hazel Szeto and colleagues, designed to accumulate within the inner mitochondrial membrane. Member of the Szeto-Schiller class of mitochondria-targeted peptides. Advanced through multiple phase-2 and phase-3 trials; conditional approval pursued for Barth syndrome.

Mechanism of Action
Binds cardiolipin, an inner-mitochondrial-membrane phospholipid central to cristae architecture and to the proper function of electron-transport-chain supercomplexes. Stabilization of cardiolipin–protein interactions preserves cristae morphology, improves electron-transport efficiency, reduces ROS generation, and supports ATP production in compromised mitochondria.

Research Indications
Primary mitochondrial myopathies (including Barth syndrome and Friedreich’s ataxia), heart failure with reduced ejection fraction, age-related macular degeneration, ischemia-reperfusion injury, renal disease with mitochondrial-dysfunction components.

Reconstitution
Typical 10 mg lyophilized vial: add **2 mL of bacteriostatic water**, swirl gently. Final concentration **5000 mcg/mL (5 mg/mL)** — each 0.2 mL (20 units on a U-100 insulin syringe) delivers 1 mg. Some trial preparations are supplied as ready-to-use injectable solutions.

Dosing Protocol (research literature)
Published trials have evaluated **4–60 mg subcutaneously once daily**, with the higher end (40 mg) used in mitochondrial-myopathy programs. Heart-failure trials have used both daily SC and IV infusion regimens. Treatment durations span **12–24 weeks** for functional endpoints. Dose individualized to indication.

Administration
Subcutaneous in most chronic protocols, rotating sites. IV infusion in selected acute and cardiac protocols. Mitochondrial accumulation is rapid; plasma half-life is short but tissue and mitochondrial residence are longer.

Storage & Handling
Lyophilized: refrigerate (2–8°C). Reconstituted: refrigerate; stable approximately **21–28 days**. Protect from light.

Side Effects
Most frequent: injection-site reactions. Less common: transient gastrointestinal upset, headache. Long-term safety data are accumulating through ongoing trial programs but remain incomplete for non-trial use.

Contraindications
Pregnancy, lactation, prior hypersensitivity. Caution in patients with significant skin sensitivity given injection-site profile at higher daily doses.

Monitoring
Baseline functional assessment appropriate to the indication (6-minute walk test for myopathy/heart failure; echocardiogram for cardiac indications). Re-measure at 12 and 24 weeks. Monitor injection-site tolerability.

Disclaimer
**This article is for informational and research-reference purposes only.** Nothing in this document constitutes medical advice, a prescription, or a recommendation from a physician. The reconstitution, dosing, and protocol information above reflects ranges commonly cited in published research and clinician-directed protocols — it is provided as reference material only, not as instructions, an endorsement of off-label use, or a substitute for individualized medical evaluation.

**Customers should do their own research and consult their own physician** before considering any peptide protocol. Whether a given compound is appropriate for an individual — and at what dose, for what duration, and alongside what monitoring — is a decision that only a licensed clinician with knowledge of that individual’s medical history, current medications, and conditions can make.