SS-31 (Elamipretide)
Also called Forzinity; Bendavia
A four-amino-acid peptide that targets mitochondria. In September 2025 the FDA granted accelerated approval to Forzinity (elamipretide) for muscle strength in Barth syndrome, a rare genetic disorder. That is not approval for fatigue, weight loss or anti-aging.
Overview
What it is
A small peptide that binds cardiolipin, a lipid in the inner mitochondrial membrane that supports energy (ATP) production.
How it works
By stabilizing cardiolipin, it is intended to improve mitochondrial structure and function.
What the research shows
Forzinity's approval relied on improved knee-extensor strength in a small Barth syndrome program; the randomized portion did not improve walking distance or fatigue. The MMPOWER-3 trial in 218 people with mitochondrial myopathy found no significant benefit in walking distance or fatigue. A 2021 study in older adults found a short-lived rise in muscle ATP capacity after one infusion, without improved muscle fatigue resistance.
Studied for
- Barth syndrome muscle strengthaccelerated approval
- Primary mitochondrial myopathyphase 3, negative
- Muscle energy in older adultssingle-dose study
Safety and regulatory status
Safety and side effects
Injection-site reactions are the most common side effect; serious allergic reactions have been reported. Severe kidney impairment may require adjustment. It contains benzyl alcohol and must not be used in newborns.
Regulatory status
Forzinity is FDA approved (accelerated) only for Barth syndrome in patients weighing at least 30 kg. Continued approval may depend on a confirmatory trial. Research "SS-31" products are not approved.
Mixing and dosing reference
Reference information only. Read before using this section.
SS-31 (30 mg Vial) Dosage Protocol
- Vial
- 30 mg SS-31
- Add diluent
- 3 mL
- Concentration
- 10 mg/mL
- 1 unit (U-100)
- 100 mcg in 0.01 mL
- Route
- Subcutaneous
- How often
- Once per day (subcutaneous injection); maintain consistent timing.
- Typical range
- 5–10 mg once daily (gradual titration); advanced protocols may reach 15–20 mg/day under supervision.
- Cycle length
- 8–12 weeks; limited data exists beyond 12 weeks.
Standard / Gradual Approach
| Week | Daily Dose (mg) | Units (per injection) (mL) |
|---|---|---|
| Weeks 1–2 | 5 mg (5000 mcg) | 50 units (0.50 mL) |
| Weeks 3–8 | 10 mg (10,000 mcg) | 100 units (1.0 mL) |
Advanced / Aggressive Approach
| Week | Daily Dose (mg) | Units (per injection) (mL) |
|---|---|---|
| Weeks 1–2 | 5 mg (5000 mcg) | 50 units (0.50 mL) |
| Weeks 3–4 | 10 mg (10,000 mcg) | 100 units (1.0 mL) |
| Weeks 5–8 | 15 mg (15,000 mcg) | Split: 2 × 75 units (0.75 mL each) |
| Optional Weeks 9–12 | 20 mg (20,000 mcg) | Split: 2 × 100 units (1.0 mL each) |
How to mix
- Draw 3.0 mL bacteriostatic water with a sterile syringe.
- Inject slowly down the vial wall; avoid vigorous shaking to prevent foaming.
- Gently swirl/roll until fully dissolved (clear solution).
- Label with reconstitution date and refrigerate at 2–8 °C (35.6–46.4 °F), protected from light; follow product-specific use-by and sterile-handling requirements.
Dosing details
- Start: 5 mg daily for Weeks 1–2 to assess individual tolerance.
- Standard Target: 10 mg daily by Week 3 (most common clinical trial dose).
- Advanced Target: 15–20 mg daily for Weeks 5+ (only for severe conditions under medical oversight).
- Frequency: Once per day (subcutaneous injection); maintain consistent timing.
- Cycle Length: 8–12 weeks; limited data exists beyond 12 weeks.
- Timing: Any consistent time; rotate injection sites to prevent tissue irritation.
Storage
- Lyophilized: Store at −20 °C (−4 °F) in original sealed vial; keep dry and protected from light. The shelf life depends on the exact product’s stability testing.
- Reconstituted: Refrigerate at 2–8 °C (35.6–46.4 °F) immediately after mixing; follow product-specific use-by and sterile-handling requirements.
- Avoid freeze–thaw: Do not refreeze reconstituted solution; prepare aliquots if needed to minimize temperature fluctuations.
- Allow refrigerated vials to reach room temperature before opening to reduce condensation inside the vial.
Administration technique
- General subcutaneous injection guidance from clinical best‑practice resources.
- Site Preparation: Clean the vial stopper and injection site with alcohol swabs; allow to air‑dry completely (30–60 seconds) before proceeding.
- Drawing the Dose: Use a new sterile insulin syringe for each injection; draw the prescribed volume from the refrigerated vial; remove any visible air bubbles by gently tapping the syringe.
- Injection Angle: Pinch a fold of skin (approximately 1–2 inches); insert the needle at 45–90° depending on subcutaneous tissue thickness (90° for most adults; 45° if very lean).
- Administration: Do not aspirate for subcutaneous injections; inject slowly and steadily over 3–5 seconds; wait 5–10 seconds before withdrawing the needle to minimize leakage.
- Site Rotation: Rotate systematically between injection sites (abdomen at least 2 inches from navel, outer thighs, upper arms, upper buttocks) to prevent lipohypertrophy and local irritation.
- Post‑Injection: Apply gentle pressure with a clean alcohol swab or cotton ball for a few seconds; do not massage the site vigorously. A small bandage may be applied if needed.
- Disposal: Immediately place used syringes in a designated sharps container; never recap needles or dispose of them in regular trash.
Important notes
- Use new sterile insulin syringes for each injection; dispose in a sharps container immediately after use.
- Rotate injection sites systematically (abdomen, thighs, upper arms) to reduce local irritation and prevent lipohypertrophy.
- Inject slowly over several seconds; wait briefly before withdrawing the needle to prevent leakage.
- Mild injection‑site reactions (redness, itching, transient discomfort) are the most common side effects reported in clinical trials; these typically resolve within hours.
- Document daily dose, injection site, and any adverse reactions to maintain consistency and identify patterns.
- For doses requiring split injections (≥15 mg), space injections at least 2 inches apart on different body regions.
Protocol source: PeptideDosages.com
Common questions
Is SS-31 FDA approved?
Only Forzinity, for Barth syndrome.
Can it help with weight loss?
The trials did not study weight loss.
Does more ATP mean more energy?
Not necessarily; the older-adult study saw no fatigue improvement.
Related in Healthy Aging
Sources and further reading (6)
- FDA. Drug Trials Snapshots: Forzinity, Sept 2025.
- DailyMed. Forzinity prescribing information.
- Karaa A, et al. Elamipretide in primary mitochondrial myopathy (MMPOWER-3). Neurology, 2023.
- Roshanravan B, et al. Elamipretide and mitochondrial ATP production in older adults. PLoS One, 2021.
- MedlinePlus Genetics. Barth syndrome.
- Source summary: PeptideDosages.com research overview (rewritten for NVO).
Laboratory research material: SS-31 Research Use Only