Vasoactive intestinal peptide
Human RCTVIP · Aviptadil · ZYESAMI · RLF-100
A 28-residue neuropeptide that dilates vessels and protects alveolar cells. Synthetic aviptadil was trialled intravenously in critical COVID-19 respiratory failure; the largest randomised trial did not show benefit.
HSDAVFTDNYTRLRKQMAVKKYLNSILN
Not approved; emergency-use requests for aviptadil in COVID-19 were declined. Trial results are mixed to negative.
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Apelin-13
Human trials (limited)APLN C-terminal fragment · Pyr-apelin-13
Apelin-13 acts as a positive inotrope and vasodilator through the APJ receptor, with extensive rodent cardiovascular pharmacology behind it. Small human infusion studies have measured forearm blood flow and cardiac output effects, but no apelin drug has completed a large trial or reached approval.
QRPRLSHKGPMPF
Not approved by FDA or EMA. Investigational.
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Elabela
Animal / in-vitro onlyELA-32 · Apela · Toddler
Elabela was identified independently by two groups in 2013 as an APJ ligand essential for cardiac development. Functional evidence is developmental-biology and animal-model based, with emerging interest in preeclampsia; there are no human interventional trials.
32-residue mature peptide (see Chng et al. 2013); shorter ELA-21 and ELA-11 fragments are also studied
Not approved. Basic-research compound.
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Angiotensin-(1-7)
Animal / in-vitro onlyAng-(1-7) · TXA127
The ACE2/Ang-(1-7)/Mas axis is among the best-characterised counter-regulatory arms of cardiovascular pharmacology, with a large rodent literature. Human work is confined to small early-phase studies of synthetic analogues.
DRVYIHP
Not approved. A synthetic formulation (TXA127) has held orphan-drug designations without full approval.
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Serelaxin
Human RCTRLX030 · recombinant human relaxin-2
An initially positive phase 3 trial in acute heart failure suggested a mortality signal, but the much larger confirmatory RELAX-AHF-2 trial found no benefit and the programme was stopped. It is a useful cautionary example of a peptide with genuinely strong trial data that did not survive replication.
Two-chain insulin-fold hormone: A-chain 24 aa, B-chain 29 aa (UniProt P04808)
Not approved by FDA or EMA. Development was discontinued after the RELAX-AHF-2 trial in 2017.
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Bivalirudin
Approved drugHirulog · Angiomax
Bivalirudin was validated in large randomised trials including REPLACE-2 and HORIZONS-AMI as an alternative to heparin plus glycoprotein IIb/IIIa blockade. Its advantage over modern heparin regimens remains debated in later trials.
FPRPGGGGNGDFEEIPEEYL (D-Phe at position 1)
FDA-approved in 2000 and EMA-approved as an anticoagulant during percutaneous coronary intervention.
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Eptifibatide
Approved drugIntegrilin
Large phase 3 trials including PURSUIT and ESPRIT established reductions in ischaemic events during acute coronary syndromes and PCI. Use is now more selective given bleeding risk and better oral antiplatelet options.
Cyclic Mpr-Har-Gly-Asp-Trp-Pro-Cys-NH2
FDA-approved in 1998 and EMA-approved for acute coronary syndromes and PCI.
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