VIP

Vasoactive intestinal peptide (VIP) is an endogenous 28-amino-acid peptide with vascular, airway and immune signaling roles. Aviptadil is the synthetic VIP investigated in the TESICO trial. A biological role is a reason to investigate treatment, not proof that every VIP product improves respiratory disease.

Human studies have produced different results across intravenous and inhaled delivery. Those preparations should not be treated as interchangeable with a general intranasal wellness protocol.

VIP-2 is retained here as an unverified search term, not a confirmed synonym of the 28-amino-acid peptide. Published uses include a VIP-2 receptor and a VIP2 label for a VIP–phentolamine combination. These distinct uses do not establish the identity of a product described only as VIP-2.

VIP receptor signaling can affect vascular tone, airway smooth muscle and inflammatory responses. The original TESICO report describes the rationale for protecting alveolar type II cells and modulating pulmonary inflammation in severe COVID-19.

That mechanistic rationale did not translate into a significant improvement in the trial’s primary clinical outcome. Receptor activity or laboratory anti-inflammatory findings do not establish a clinical benefit for chronic inflammatory syndromes.

A 2025 inhaled aviptadil study enrolled 80 patients at nine centers. Inhaled treatment plus standard care was associated with a shorter mean hospital stay, 7.8 versus 10 days (P=0.049), and improved day-28 CT findings. No adverse-event withdrawals were reported in its indexed abstract.

This is encouraging route-specific evidence, but the small study does not establish a reliable mortality benefit, routine nasal use, or treatment of every form of immune dysregulation. It should be considered alongside the larger negative intravenous trial rather than replacing it.

TESICO used three 12-hour intravenous infusions on consecutive days, with escalating doses of 600, 1,200 and 1,800 pmol/kg. This was a monitored hospital protocol for acute hypoxemic respiratory failure.

The inhaled trial studied a different preparation and clinical setting. Neither cited study validates a universal intranasal microgram schedule, cycling plan, rapid symptom-onset promise or home combination with other peptides.

In TESICO, 471 patients were randomized to aviptadil or placebo and 461 received treatment. The trial stopped for futility. The 90-day ordinal clinical outcome was not significantly better with aviptadil: odds ratio 1.11 (95% CI 0.80–1.55; P=0.54). Mortality was 38% versus 36%, without a significant difference.

The smaller inhaled report is useful emerging evidence. Its results do not reverse the intravenous finding or demonstrate that nasal sprays have the same exposure or benefit.

In TESICO, infusion-associated diarrhea occurred in 39.8% versus 11.3%, flushing in 14.7% versus 6.1%, and hypotension in 58.4% versus 41.3%. These figures concern critically ill patients receiving the study’s intravenous regimen, not the incidence for every VIP route.

The overall five-day safety composite was 63% versus 56% (P=0.10). Individual infusion reactions and the nonsignificant composite should both be represented. The cited studies do not establish long-term nasal safety or the safety of peptide combinations.

VIP has a plausible biological rationale and human clinical research, including both positive and neutral findings. The large intravenous trial did not show clinical benefit, while the smaller inhaled study supports further investigation in its own setting.

Evidence should be matched to the formulation, delivery route, population and outcome being considered.

We read the original TESICO full report for trial design, clinical outcomes and safety, and the indexed abstract of the 2025 inhaled study; its full text was not obtained. This review does not adjudicate a current complete US product-approval search or certify related guides. Editorial review is separate from clinician sign-off.