SS-31 / Elamipretide BAC Water & Reconstitution Guide
SS-31, also known as elamipretide, is a mitochondria-targeted tetrapeptide that has been investigated for mitochondrial bioenergetics, mitochondrial myopathy, cardiovascular disease, ophthalmic disease and Barth syndrome. In the United States, elamipretide is now an FDA-approved prescription drug under the name Forzinity for improving muscle strength in patients with Barth syndrome who weigh at least 30 kg.
How Much BAC Water for SS-31 / Elamipretide?
There is not necessarily one universal BAC-water volume for an SS-31 research quantity. The liquid volume selected determines the resulting mathematical concentration.
Adding more liquid produces a lower concentration, while adding less liquid produces a higher concentration, assuming the total peptide quantity remains constant.
SS-31 / Elamipretide BAC Water Concentration Chart
The following table demonstrates the mathematical concentration resulting from different liquid volumes. The 5 mg, 10 mg and 20 mg quantities are calculation examples and are not claimed to be standardized commercial SS-31 vial strengths.
| Peptide Quantity | 1 mL | 2 mL | 2.5 mL | 3 mL | 5 mL |
|---|---|---|---|---|---|
| 5 mg SS-31 | 5 mg/mL | 2.5 mg/mL | 2 mg/mL | 1.67 mg/mL | 1 mg/mL |
| 10 mg SS-31 | 10 mg/mL | 5 mg/mL | 4 mg/mL | 3.33 mg/mL | 2 mg/mL |
| 20 mg SS-31 | 20 mg/mL | 10 mg/mL | 8 mg/mL | 6.67 mg/mL | 4 mg/mL |
Need a different vial quantity or liquid volume?
Use the BacScience Universal BAC Water Calculator for custom concentration calculations.
Calculation note: Concentration = total peptide quantity ÷ liquid volume. These calculations do not establish sterility, stability, compatibility, biological activity, clinical suitability, or an administration dose.
How Much BAC Water Should Be Added to SS-31 / Elamipretide?
There is no single BAC-water quantity that should be presented as a universal SS-31 reconstitution instruction. The answer depends on the starting quantity and the target concentration. The mathematical relationship is straightforward:
How much BAC water for 5 mg of SS-31?
As a mathematical example, 5 mg divided by 1 mL produces 5 mg/mL; 5 mg divided by 2 mL produces 2.5 mg/mL; and 5 mg divided by 5 mL produces 1 mg/mL.
How much BAC water for 10 mg of SS-31?
For mathematical concentration purposes, 10 mg divided by 1 mL produces 10 mg/mL, while 10 mg divided by 2 mL produces 5 mg/mL and 10 mg divided by 5 mL produces 2 mg/mL.
How does BAC-water volume change SS-31 concentration?
Increasing liquid volume decreases the calculated concentration. Decreasing liquid volume increases the calculated concentration, assuming the total peptide quantity remains unchanged.
Understanding SS-31 Concentration
Concentration and dose are different scientific concepts. Concentration describes how much compound exists per unit volume. Dose describes an amount administered to a subject within a defined experimental or clinical protocol.
Quantity
Total amount of peptide represented by a sample, expressed for example in mg.
Concentration
Amount of compound per volume, commonly expressed as mg/mL.
Dose
Amount administered within a specific research or approved clinical protocol.
What Is SS-31 / Elamipretide?
SS-31, also known as elamipretide, is a mitochondria-targeted aromatic-cationic tetrapeptide. Scientific literature describes the compound as a peptide that can localize to the inner mitochondrial membrane and interact with cardiolipin, a phospholipid that is particularly abundant in the inner mitochondrial membrane.
Research has examined whether this mitochondrial targeting can influence membrane organization, oxidative stress, ATP production, mitochondrial respiration and cellular bioenergetics.
How Does SS-31 / Elamipretide Work?
Mitochondrial targeting
SS-31 is an aromatic-cationic peptide that can preferentially localize to mitochondria and associate with the inner mitochondrial membrane.
Cardiolipin interaction
Research indicates that SS-31 interacts with cardiolipin and can alter membrane surface electrostatics and lipid packing under experimental conditions.
Mitochondrial function
Experimental studies have investigated ATP production, mitochondrial respiration, oxidative stress and mitochondrial membrane function following elamipretide exposure.
What Is SS-31 / Elamipretide Being Studied For?
Barth Syndrome
FDA approved Forzinity (elamipretide) in 2025 to improve muscle strength in adult and pediatric patients with Barth syndrome weighing at least 30 kg.
FDA accelerated approvalPrimary mitochondrial myopathy
Elamipretide has been evaluated in randomized trials of primary mitochondrial myopathy. The MMPOWER-3 Phase 3 study did not meet its primary endpoints for walking performance and fatigue.
Phase 3 evidenceCardiovascular & ophthalmic disease
Studies have also evaluated elamipretide in heart failure, age-related macular degeneration and other conditions. These research indications should not be confused with the FDA-approved Barth syndrome indication.
InvestigationalFDA Status of Elamipretide
Forzinity (elamipretide)
On September 19, 2025, the U.S. Food and Drug Administration granted accelerated approval to Forzinity (elamipretide) as the first FDA-approved treatment for Barth syndrome in patients weighing at least 30 kg.
The approved indication is specifically to improve muscle strength in adult and pediatric patients with Barth syndrome weighing at least 30 kg. The approval was based on an intermediate clinical endpoint and requires confirmatory evidence of clinical benefit.
FDA labeling identifies Forzinity as a sterile aqueous solution containing 280 mg in 3.5 mL, equivalent to 80 mg/mL.
Human Clinical Research
Elamipretide has been evaluated in multiple human clinical programs. Importantly, outcomes differ by disease and trial. Evidence from one condition cannot automatically be transferred to another.
| Study | Population | Dose Studied | Route | Duration | Key Finding |
|---|---|---|---|---|---|
| MMPOWER-2 | 30 adults with primary mitochondrial myopathy | 40 mg/day | SC | 4 weeks | Primary 6MWT endpoint did not reach statistical significance; secondary symptom measures showed signals. |
| MMPOWER-3 | 218 adults with genetically confirmed PMM | 40 mg/day | SC | 24 weeks | Primary 6MWT and fatigue endpoints were not improved versus placebo. |
| HFrEF Phase 2 | 71 patients with HFrEF | 4 or 40 mg/day | SC | 28 days | No significant improvement in LV end-systolic volume. |
| TAZPOWER | Patients with Barth syndrome | 40 mg/day | SC | Multiple treatment periods | Clinical development supporting the eventual FDA accelerated approval for Barth syndrome. |
| ReCLAIM | Adults with dry AMD / geographic atrophy | 40 mg/day | SC | 24–48 weeks depending on study | Investigational ophthalmic research; not an FDA-approved indication. |
Doses Studied in Published Research
Elamipretide has been evaluated through several administration routes and dosing schedules. Examples include intravenous infusion studies, subcutaneous clinical trials and the current FDA-approved pharmaceutical formulation.
40 mg/day SC
This dose has been investigated in multiple subcutaneous clinical trials, including MMPOWER-2, MMPOWER-3 and Barth syndrome studies.
4–40 mg/day
A Phase 2 heart-failure study compared subcutaneous elamipretide doses of 4 mg and 40 mg daily with placebo.
80 mg/mL
FDA-approved Forzinity is supplied as a sterile aqueous solution at 80 mg/mL in a 280 mg/3.5 mL vial.
Preclinical & In-Vitro Research
Before and alongside clinical development, SS-31 was investigated in cellular, biochemical and animal models. These studies have examined mitochondrial respiration, membrane structure, oxidative stress, ATP production and tissue-specific mitochondrial function.
Mitochondrial membrane biology
Biophysical research has examined how SS-31 associates with lipid membranes and alters membrane electrostatics and lipid packing.
ATP & respiration
Research has examined mitochondrial ATP production, oxygen consumption, membrane potential and ADP sensitivity.
Disease models
Animal models have investigated mitochondrial protection in conditions including ischemic injury, neurodegeneration, kidney disease and spinal cord injury.
SS-31 Research Reconstitution & Concentration
When a research sample is described by a total peptide quantity and a liquid volume, concentration can be calculated using the following equation:
Worked mathematical examples
Example 1
5 mg ÷ 1 mL
5 mg/mLExample 2
10 mg ÷ 2.5 mL
4 mg/mLExample 3
20 mg ÷ 5 mL
4 mg/mLBAC Water vs. SS-31 Concentration
Lower concentration
More liquid distributes the same total peptide quantity through a larger volume, producing a lower mg/mL value.
Higher concentration
Less liquid distributes the same total peptide quantity through a smaller volume, producing a higher mg/mL value.
Does not change
Changing the mathematical liquid volume does not change the total amount of peptide represented by the starting quantity.
Calculate a custom SS-31 concentration
Enter your own peptide quantity and liquid volume.
Research Limitations & Safety
Approved pharmaceutical use is indication-specific
FDA approval of Forzinity does not mean that elamipretide is FDA-approved for every condition investigated in research. The approved indication is specifically improving muscle strength in patients with Barth syndrome who weigh at least 30 kg.
Clinical research does not equal a general treatment protocol
- Different trials used different populations and endpoints.
- Route and formulation varied among studies.
- Results in primary mitochondrial myopathy cannot automatically be transferred to other diseases.
- Historical experimental doses are not general dosing advice.
- A mathematical concentration does not determine a clinically appropriate dose.
SS-31 / Elamipretide BAC Water FAQ
How much BAC water should be used for SS-31?
How much BAC water for 5 mg of SS-31?
How much BAC water for 10 mg of SS-31?
What is the SS-31 reconstitution formula?
Is SS-31 the same thing as elamipretide?
Is elamipretide FDA approved?
What concentration is FDA-approved Forzinity?
Does FDA-approved Forzinity need BAC-water reconstitution?
Has SS-31 been studied in humans?
Did elamipretide work in the Phase 3 mitochondrial myopathy trial?
Does adding more liquid change the total amount of SS-31?
Where can I calculate a custom SS-31 concentration?
Related BacScience Research Resources
BAC Water Calculator
Calculate mathematical concentration from a custom peptide quantity and liquid volume.
Open BAC Water Calculator →Research Compound Library
Explore related research compounds and scientific concentration resources.
Research Compound Library →Testing & Transparency
Explore BacScience resources covering testing, documentation, COAs and research transparency.
Testing & Transparency →# are intentionally placeholders. Insert only confirmed BacScience URLs rather than creating unverified internal links.Scientific References
FDA-approved labeling identifying the indication, formulation and dosage form.
View FDA prescribing information
FDA announcement dated September 19, 2025.
View FDA announcement
Neurology. 2023. Phase 3 randomized clinical trial of elamipretide in primary mitochondrial myopathy.
View PubMed record
Randomized crossover trial of subcutaneous elamipretide in adults with primary mitochondrial myopathy.
View PubMed record
Randomized placebo-controlled study of elamipretide in heart failure with reduced ejection fraction.
View PubMed record
Research examining mitochondrial function, ATP production, ADP sensitivity and mitochondrial bioenergetics.
View PubMed record
Biophysical research investigating SS-31 binding to lipid bilayers and mitochondrial membrane electrostatics.
View PubMed record
Clinical research evaluating 40 mg/day subcutaneous elamipretide in Barth syndrome.
View PubMed record
Long-term open-label extension data from the TAZPOWER program.
View PubMed record
Last Scientifically Reviewed
September 10, 2026
This page was reviewed against current FDA information and published scientific literature concerning SS-31 / elamipretide, including FDA-approved Forzinity labeling, clinical trials and mechanistic mitochondrial research.
Scientific reviewer: BacScience Scientific Content Team
Content scope: Research education, concentration mathematics, regulatory status and scientific literature interpretation.