ss-31 vs cibinetide

ss-31 (A-tier) vs cibinetide (D-tier). mechanism, trials, evidence boundaries, dosing literature. side-by-side reference.

ss-31 · tier A

the first mitochondria-targeted peptide drug. FDA-approved september 2025. for Barth syndrome, studied for heart failure.

the first FDA-approved peptide drug that targets mitochondria. Forzinity for Barth syndrome, ~$800,000 a year.

FDA '25 elamipretide · Barth syndrome · half-life 3-4 hours in circulation; functional effects persist 12-16 hours due to mitochondrial retention · healing

cibinetide · tier D

eleven amino acids copied from erythropoietin, the hormone that tells the body to make more red blood cells. the copy keeps the half of that hormone which protects injured tissue and leaves the red cells alone. vendors label it ARA-290. six published human trials, five of them randomised, and two primary endpoints that separated.

does it work: mixed. it was tested mostly in people whose smallest nerves had been damaged by sarcoidosis or by diabetes, and it never beat placebo on how much pain those people were in. two main endpoints did beat placebo across the whole human record. one was the amount of nerve visible in photographs of the eye surface, at one dose out of three, corneal nerve fibre area at 4 mg (p=0.012). the other was an average blood-sugar reading in a diabetes trial, HbA1c in type 2 diabetes (p=0.002). nobody outside the group that invented it has repeated either. roughly 130 people have ever been dosed.

1 of 3 doses beat placebo · half-life ~2 min in plasma, from a developer-authored review; no primary human PK paper located · healing

at a glance

• ss-31: tier A · FDA '25 elamipretide · Barth syndrome
• cibinetide: tier D · 1 of 3 doses beat placebo

reptides grades the research record and cites the literature behind every call. research reference only; not medical advice.