RecruitingPhase 4NCT07531251
Clinical Trial in Patients With Barth Syndrome- 4TAZPower
Stealth BioTherapeutics Inc.n = 482 Jul 2026 to est. 30 Nov 2029
Barth Syndrome
Elamipretide (SS-31) / Studies
Synthetic analog · 4 amino acids · 639.8 Da
Elamipretide (SS-31) studies and research data
PepBank has 372 SS-31 studies with results. 299 of them gave SS-31, with 1,784 results, grouped by what the studies measured. In each group, results from studies in people come first. Data as of 2026-10-30.
Searches 1,784 results and 555 papers. Newer studies from Europe PMC
Results in people
129
7% of 1,784 results
Results in animals
1,109
62% of 1,784 results
Results in lab cells
546
31% of 1,784 results
From computer models
0
0% of 1,784 results
The molecule
SS-31 identity
Identifiers, parent molecule, targets and development stage, from curated data.
Elamipretide (SS-31, MTP-131) is the synthetic tetrapeptide D-Arg-2,6-dimethyl-Tyr-Lys-Phe-NH2, from the Szeto-Schiller series of cell-permeable peptides that concentrate in the inner mitochondrial membrane. The FDA label describes it as a mitochondrial cardiolipin binder; a 2024 CRISPR screen proposed phospholipid scramblase 3 as a target. FDA approved elamipretide hydrochloride (Forzinity, Stealth BioTherapeutics) on 2025-09-19 under accelerated approval to improve muscle strength in Barth syndrome patients weighing at least 30 kg.
- Kind
- Synthetic analog · 4 residues
- Identifiers
- ChEMBLCHEMBL3833370 (opens in a new tab)CHEMBL4298161 (opens in a new tab)PubChem CID11764719 (opens in a new tab)UNII87GWG91S09 (opens in a new tab)E40WZ3BK2D (opens in a new tab)DrugBankDB11981 (opens in a new tab)CAS736992-21-52244098-12-0KEGGD10925 (opens in a new tab)D11542 (opens in a new tab)IUPHAR14276 (opens in a new tab)
- Development
- Approved in the US (Forzinity, 2025)Stealth BioTherapeuticsAccelerated approval (US). A phase 3b/4 placebo-controlled trial in Barth syndrome (NCT07531251, 4TAZPower) started 2026-07-02. Phase 3 trials in primary mitochondrial myopathy (NCT05162768 completed; NCT03323749 terminated) and in dry age-related macular degeneration (ReNEW, NCT06373731, active, not recruiting). ChEMBL max_phase is 3 and does not reflect the 2025 approval. Source (opens in a new tab)
Targets
| Target | Action | Evidence |
|---|---|---|
| Cardiolipin (inner mitochondrial membrane phospholipid) | Binder | approved-drug labelSource (opens in a new tab) |
| Phospholipid scramblase 3PLSCR3Q9NRY6 (opens in a new tab) | Binder (proposed) | primary literatureSource (opens in a new tab) |
Sequence and structure
Residues, differences from the parent, calculated properties and 3D structure. Source values and calculated values are shown separately.
Sequence
4 amino acids · 3 modifications
H-
Residues 1 to 4:
KF
Properties
From identity sources
- Formula
- C32H49N9O5
- Molecular weight
- 639.8 g/mol
- Monoisotopic mass
- 639.3857 Da
- GSRS UNII 87GWG91S09(opens in a new tab)retrieved 2026-10-08
- PubChem CID 11764719(opens in a new tab)retrieved 2026-10-08
- ChEMBL CHEMBL3833370(opens in a new tab)retrieved 2026-10-08
- ChEMBL CHEMBL4298161(opens in a new tab)retrieved 2026-10-08
- Curated KEGG D10925(opens in a new tab)retrieved 2026-10-08
- Curated KEGG D11542(opens in a new tab)retrieved 2026-10-08
- Curated FDA label FORZINITY(opens in a new tab)retrieved 2026-10-08
Calculated from the sequence
Some values cannot be calculated. The sequence has a non-canonical residue (X). Residue tables cover only the 20 standard amino acids.
- Average mass
- Not calculated
- Monoisotopic mass
- Not calculated
- Isoelectric point (pI)
- Not calculated
- Net charge at pH 7.4
- Not calculated
- GRAVY (hydropathy)
- Not calculated
- Extinction coefficient, 280 nm (Cys reduced)
- 0 M⁻¹ cm⁻¹
- 5500 x Trp + 1490 x Tyr · Pace et al. 1995 (ExPASy ProtParam)
- No Trp or Tyr: absorbance at 280 nm cannot measure this peptide.
- Instability index
- Not calculated
- Aliphatic index
- Not calculated
- Boman index
- Not calculated
- Hydrophobic moment (μH)
- Not calculated
- 1 non-canonical residue (X) is not included in calculated values.
- D-amino acids have the same mass and charge as L forms. Hydrophobicity scales were measured on L forms.
- Defined and validated for proteins; use with care for short peptides.
- Assumes an ideal alpha helix. Many short peptides are not helical.
@pepdb/chem 0.2.0 · EMBOSS pKa set · ExPASy residue masses
Net charge by pH
No charge curve
The sequence has a non-canonical residue (X). Residue tables cover only the 20 standard amino acids.
Composition
- Aromatic25% (1)F
- Positive50% (2)K R
- Non-canonical25% (1)X
4 residues. Each residue counts in one class; F and W count as aromatic.
A Ala0 · 0%
I Ile0 · 0%
L Leu0 · 0%
M Met0 · 0%
V Val0 · 0%
F Phe1 · 25%
W Trp0 · 0%
Y Tyr0 · 0%
H His0 · 0%
K Lys1 · 25%
R Arg1 · 25%
D Asp0 · 0%
E Glu0 · 0%
N Asn0 · 0%
Q Gln0 · 0%
S Ser0 · 0%
T Thr0 · 0%
C Cys0 · 0%
G Gly0 · 0%
P Pro0 · 0%
X Xaa1 · 25%
3D structure
No 3D structure
No experimental structure (PDB) and no UniProt entry for an AlphaFold model are listed for this peptide. Synthetic peptides often have neither. The sequence view above is the reference.
2D structure
Draws the structure in your browser with RDKit (about 2.3 MB, loaded once).
SMILES fromPubChem CID 11764719(opens in a new tab)
CC1=CC(=CC(=C1C[C@@H](C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CC2=CC=CC=C2)C(=O)N)NC(=O)[C@@H](CCCN=C(N)N)N)C)OResults by area
What the studies measured
People first in each area, then animals, then lab cells. Counts are exact and come from studies that gave the peptide.
Trials and papers
Newer studies
PepBank reads each paper before it shows the results. This search looks in Europe PMC for newer papers that PepBank has not read yet.
Status and safety
Data