SS-31 50 mg

SS-31 50 mg (Elamipretide) research-grade lyophilized peptide powder in a glass vial. SS-31 is a mitochondria-targeting tetrapeptide studied for its interaction with cardiolipin, mitochondrial integrity and cellular bioenergetics in experimental models.

Research Overview

SS-31 (Elamipretide) is a mitochondria-targeting tetrapeptide that selectively associates with cardiolipin in the inner mitochondrial membrane. In experimental models it is used as a tool compound to investigate mitochondrial integrity, electron transport chain efficiency and cellular responses to oxidative stress.

Primary Research Areas

• Mitochondrial function & bioenergetics: studies of oxidative phosphorylation, ATP production and mitochondrial coupling efficiency [7].
• Cardiolipin interaction & membrane structure: models examining inner mitochondrial membrane stability and electron transport chain organization [3,8].
• Oxidative stress & ROS signaling: experiments on reactive oxygen species generation, redox balance and mitochondrial protection [7].
• Ischemia–reperfusion & tissue stress models: preclinical systems exploring mitochondrial resilience under acute or chronic stress conditions [8].
• Walking and tiredness in mitochondrial disease: in a phase 3 trial, 218 adults with genetically confirmed mitochondrial muscle disease injected 40 mg a day for 24 weeks and did no better than placebo: 3.2 metres less on a six-minute walk, no change in fatigue score. The mitochondrial framing is real; the trial built to prove it in people did not [1,2].
• Barth syndrome: twelve people with Barth syndrome took 40 mg a day for 12 weeks against placebo and neither main measure moved. The eight who continued openly to 36 weeks walked 95.9 metres further than at the start and gained knee-extension strength. An extension with no placebo arm cannot separate the drug from practice and expectation [3].
• Sight in dry macular degeneration: in a 48-week trial, 176 people with the dry form of age-related macular degeneration injected 40 mg a day and beat placebo on neither main measure. Treated eyes did lose the photoreceptor layer about 43% more slowly on scans, a secondary finding the trial was not designed to prove [4].
• Heart failure: a single four-hour infusion shrank the failing left ventricle in the eight people given the highest dose, by roughly 18 ml at end-diastole and 14 ml at end-systole. Four weeks of daily injections in 71 people then changed nothing against placebo. One infusion moving an imaging number is not a heart that works better [5,6].
• Endurance in old age: old mice, 26 months of age, given 3 mg/kg a day for eight weeks had calf muscle that resisted fatigue better and weighed more, and they lasted significantly longer on a treadmill than untreated old mice. Nothing like this has been shown in healthy people [7].
• Reactions where the needle goes in: it is a daily injection under the skin and the skin reacts: 80% of the 30 adults in one crossover trial had injection-site reactions, mostly mild, with no serious events or deaths. In the 176-person eye trial 86% of the treated group reported some adverse event, most often itching, pain, bruising and redness [2,4].

References

1. Karaa A, Bertini E, Carelli V, et al. Efficacy and Safety of Elamipretide in Individuals With Primary Mitochondrial Myopathy: The MMPOWER-3 Randomized Clinical Trial. Neurology. 2023;101(3):e238-e252. PMID 37268435. doi:10.1212/WNL.0000000000207402
2. Karaa A, Haas R, Goldstein A, et al. A randomized crossover trial of elamipretide in adults with primary mitochondrial myopathy. J Cachexia Sarcopenia Muscle. 2020;11(4):909-918. PMID 32096613. doi:10.1002/jcsm.12559
3. Reid Thompson W, Hornby B, Manuel R, et al. A phase 2/3 randomized clinical trial followed by an open-label extension to evaluate the effectiveness of elamipretide in Barth syndrome, a genetic disorder of mitochondrial cardiolipin metabolism. Genet Med. 2021;23(3):471-478. PMID 33077895. doi:10.1038/s41436-020-01006-8
4. Ehlers JP, Hu A, Boyer D, et al. ReCLAIM-2: A Randomized Phase II Clinical Trial Evaluating Elamipretide in Age-related Macular Degeneration, Geographic Atrophy Growth, Visual Function, and Ellipsoid Zone Preservation. Ophthalmol Sci. 2025;5(1):100628. PMID 39605874. doi:10.1016/j.xops.2024.100628
5. Daubert MA, Yow E, Dunn G, et al. Novel Mitochondria-Targeting Peptide in Heart Failure Treatment: A Randomized, Placebo-Controlled Trial of Elamipretide. Circ Heart Fail. 2017;10(12). PMID 29217757. doi:10.1161/CIRCHEARTFAILURE.117.004389
6. Butler J, Khan MS, Anker SD, et al. Effects of Elamipretide on Left Ventricular Function in Patients With Heart Failure With Reduced Ejection Fraction: The PROGRESS-HF Phase 2 Trial. J Card Fail. 2020;26(5):429-437. PMID 32068002. doi:10.1016/j.cardfail.2020.02.001
7. Campbell MD, Duan J, Samuelson AT, et al. Improving mitochondrial function with SS-31 reverses age-related redox stress and improves exercise tolerance in aged mice. Free Radic Biol Med. 2019;134:268-281. PMID 30597195. doi:10.1016/j.freeradbiomed.2018.12.031
8. Saad A, Herrmann SMS, Eirin A, et al. Phase 2a Clinical Trial of Mitochondrial Protection (Elamipretide) During Stent Revascularization in Patients With Atherosclerotic Renal Artery Stenosis. Circ Cardiovasc Interv. 2017;10(9). PMID 28916603. doi:10.1161/CIRCINTERVENTIONS.117.005487