VIP is a naturally occurring signaling peptide with a wide range of physiological
roles and a synthetic counterpart that has been studied clinically.
Chemical identity & structure.
VIP (vasoactive intestinal peptide) is a 28-amino-acid neuropeptide produced
throughout the body — in the nervous system, gut, and immune tissues. The
synthetic pharmaceutical form of VIP is called aviptadil.
Mechanism of action.
VIP acts on receptors (VPAC1 and VPAC2) found widely across tissues. Its many
reported roles include vasodilation (relaxing blood vessels and smooth muscle),
immune and anti-inflammatory modulation, support of certain lung cell types, and
involvement in circadian rhythm regulation in the brain. The breadth of VIP's
physiology is itself notable — it is a genuinely pleiotropic signaling peptide.
Key research findings.
Aviptadil (synthetic VIP) has been studied in clinical research, including in
respiratory contexts — for example, research in acute respiratory distress and
related severe lung conditions — and other indications. The clinical results
across indications have been mixed.
The research / citation base.
VIP is a well-characterized endogenous peptide with a substantial physiology
literature. Aviptadil has been the subject of clinical research and regulatory
review processes; depending on jurisdiction and indication its status varies,
and it is best described as investigational rather than a broadly approved
therapy. The respiratory-research results have been mixed.
Human clinical trial data.
In the randomised, placebo-controlled TESICO trial by Brown and colleagues (2023) in COVID-19-associated acute hypoxaemic respiratory failure, aviptadil was administered as a daily 12-h infusion for 3 days, targeting 600 pmol/kg on infusion day 1, 1200 pmol/kg on day 2, and 1800 pmol/kg on day 3; it did not significantly improve clinical outcomes up to day 90 (PubMed).
Quality & sourcing notes.
A 28-residue peptide should be confirmed on a batch-specific COA by mass
spectrometry and HPLC purity. Confirm the product describes VIP/aviptadil
specifically.
*Research-use note: Educational summary of published research. VIP/aviptadil is
investigational in most contexts; this is research context only and not medical
advice.*