VIP alternatives.

5 compounds compared to VIP, ranked by published evidence tier and regulatory status, not by what's marketed hardest.

Why people look for an alternative

VIP alternatives searches usually trace back to a specific program. The synthetic form used in human trials is aviptadil, which remains investigational in the United States and has been studied under FDA mechanisms including orphan-drug designations for pulmonary hypertension and sarcoidosis and in emergency COVID-19 trials, without general approval. The exception is geographic and narrow: the aviptadil and phentolamine combination sold as Invicorp is approved for erectile dysfunction in several countries including the UK, Denmark, and New Zealand, but not broadly in the US. So the honest split is that VIP has one approved use, in one form, in some countries, and nothing approved in the indications most people are reading about.

What you're comparing against
VIP
C tier · 50/100Research / preclinical

VIP (vasoactive intestinal peptide, also called vasoactive intestinal polypeptide) is a 28-amino-acid neuropeptide first isolated from porcine intestine in the early 1970s.

Ranked by evidence · strongest first
  1. 01
    Thymosin α-1
    C tierIn human trials
    Zadaxin

    Acts through the immune and inflammatory modulation pathway, like VIP. In human trials.

  2. 02
    Thymosin β-4
    D tierResearch / preclinical

    Acts through the immune and inflammatory modulation pathway, like VIP. Research / preclinical.

  3. 03
    KPV
    F tierResearch / preclinical

    Acts through the immune and inflammatory modulation pathway, like VIP. Research / preclinical.

  4. 04
    Thymalin
    D tierResearch / preclinical
    thymus peptide extract

    Same category: immune & inflammation. Research / preclinical.

  5. 05
    LL-37
    F tierResearch / preclinical

    Same category: immune & inflammation. Research / preclinical.

How this list is built

An “alternative” here means a compound that shares VIP's mechanism pathway or sits in the same category, not a marketing substitute. Each is ordered by PepCue's evidence tier (a weighted 0–100 score across human data, safety, replication and regulatory clarity), then by whether it's actually approved. This is a research reference, not medical or purchasing advice: an alternative sitting higher on evidence does not mean it's right, safe, or legal for any given use. Reviewed June 1, 2026.

Comparing options with your provider?

PepCue keeps every compound, dose and lab in one private, provider-ready timeline, whichever one you land on.

Educational and research reference only. Not medical advice, diagnosis, or dosing guidance. Flag an error on this page
Compounds