Compare Peptides

Select any two compounds for a side-by-side comparison of mechanism, uses, risks, and FDA regulatory status.

Popular comparisons

Thymosin Alpha-1

Tα1, Zadaxin

Category 1
Immune Support

KPV

Lys-Pro-Val, α-MSH C-terminal tripeptide

Pending PCAC
Anti-Inflammatory & Healing
Overview

A thymic peptide that plays a central role in immune system regulation. Approved as a drug in over 35 countries (though not in the US) for hepatitis B and C treatment and as an immune booster.

A tripeptide (Lysine-Proline-Valine) derived from the C-terminus of alpha-MSH (melanocyte-stimulating hormone). Has potent anti-inflammatory properties and is being studied for inflammatory bowel conditions and wound healing.

Mechanism of Action

Enhances T-cell function, promotes dendritic cell maturation, and modulates cytokine production. Acts as an immune system regulator rather than a simple stimulant, helping to balance immune responses.

Inhibits NF-κB signaling and pro-inflammatory cytokine production. Crosses the intestinal epithelium to directly suppress inflammation locally. Anti-microbial properties have also been demonstrated in vitro.

Common Uses
  • Immune system support
  • Chronic infection management
  • Cancer adjunct therapy (in some countries)
  • Post-illness recovery
  • Autoimmune condition management
  • Inflammatory bowel disease (IBD) support
  • Wound healing and skin conditions
  • General anti-inflammatory protocols
  • Gut health optimization
Known Risks
  • Generally well-tolerated in clinical use
  • Injection site reactions
  • Rare allergic reactions
  • May interact with immunosuppressive drugs
  • Very limited human clinical data
  • Optimal delivery method not established
  • Injection vs. oral bioavailability differences not fully characterized
  • Long-term safety unknown
Regulatory Status
Category 1

Reclassified to Category 1 in February 2026 as part of the HHS announcement restoring compounding access. Not affected by the April 15, 2026 Category 2 removal action. Approved as Zadaxin in 35+ countries but not FDA-approved in the US. Available through licensed 503A compounding pharmacies with a physician prescription.

Pending PCAC

Removed from FDA 503A Category 2 effective April 22, 2026. Scheduled for PCAC review on July 23, 2026 for wound healing and inflammatory conditions. Compounding not yet authorized — status is in regulatory gray zone pending PCAC recommendation.

PCAC: July 23, 2026

This comparison is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy.