🛡️ Category

Immune Support Peptides

Thymic peptides investigated for immune modulation and resilience, some used clinically outside the US.

Immune peptides span several distinct families. Thymic peptides (thymosin alpha-1, thymalin, thymopentin, thymogen, thymulin) are derived from or modeled on the thymus gland and are studied for modulating T-cell function — several are used clinically outside the US but remain unapproved domestically. Antimicrobial peptides like the human cathelicidin LL-37 are part of innate immunity, with a notable double-edged biology that also links them to inflammatory disease.

This category also contains two genuinely FDA-approved peptide drugs that work through immune-related mechanisms: icatibant (a bradykinin antagonist for hereditary angioedema) and glatiramer acetate (a polypeptide immunomodulator for multiple sclerosis) — useful reminders that "immune peptide" covers everything from unproven research chemicals to established medicines.

The peptide Thymic / immunepeptide Acts on T-cells &immune receptors Triggers Immune modulationsignals Outcome Altered immuneresponse (studied)
Simplified mechanism: how immune peptides are generally studied to act. Individual peptides vary — see each guide.

Immune Support peptides we cover (14)

Immune

Thymosin Alpha-1

Tα1, Zadaxin

A naturally occurring thymic peptide that modulates immune function, approved in some countries (as Zadaxin) for hepatitis and as a vaccine adjuvant.

Read the guide →
ImmuneAnti-Aging

Thymalin

A thymus-derived peptide preparation studied — largely in Russia — for restoring immune balance and as part of peptide bioregulation research on aging.

Read the guide →
ImmuneHealing

LL-37

Cathelicidin (human)

The body's main cathelicidin antimicrobial peptide, central to innate immunity and wound healing — but with a complex, context-dependent (and sometimes harmful) biology.

Read the guide →
HealingImmune

KPV

Lys-Pro-Val (α-MSH fragment)

A tripeptide fragment of α-MSH studied for anti-inflammatory effects, particularly in the gut and skin, without α-MSH's pigmentation activity.

Read the guide →
HealingImmune

ARA-290

Cibinetide

A peptide derived from the tissue-protective region of erythropoietin (EPO) — without EPO's red-blood-cell effects — studied in trials for neuropathic pain and small-fiber neuropathy.

Read the guide →
Immune

Thymogen

Glutamyl-Tryptophan (γ-D-Glu-Trp)

A simple synthetic dipeptide (glutamyl-tryptophan) developed in Russia as an immunomodulator, used there for immune support during infections.

Read the guide →
Immune

Thymulin

FTS (facteur thymique sérique)

A zinc-dependent thymic hormone (a nonapeptide) involved in T-cell maturation, studied for immune regulation, inflammation, and pain.

Read the guide →
Immune

Thymopentin

TP-5, Timunox

A synthetic pentapeptide corresponding to the active site of the thymic hormone thymopoietin, studied and marketed in some countries as an immunomodulator.

Read the guide →
Immune

Icatibant

Firazyr

A bradykinin B2 receptor antagonist peptide, FDA-approved (as Firazyr) to treat acute attacks of hereditary angioedema.

Read the guide →
Immune

Glatiramer Acetate

Copaxone

A random polypeptide mixture of four amino acids and an FDA-approved immunomodulator (Copaxone) for relapsing-remitting multiple sclerosis.

Read the guide →
Immune

VIP

Vasoactive Intestinal Peptide, Aviptadil

A 28-amino-acid neuropeptide with vasodilatory, anti-inflammatory, and immune-regulating roles; its synthetic form (aviptadil) has been investigated for lung conditions such as ARDS.

Read the guide →
Immune

Enfuvirtide

Fuzeon, T-20

A 36-amino-acid peptide and the first HIV fusion inhibitor (Fuzeon), FDA-approved to block HIV-1 from entering host cells in treatment-experienced patients.

Read the guide →
Immune

Vilon

Lys-Glu (KE)

A short dipeptide bioregulator (Lys-Glu) from the Khavinson research line, studied — largely in Russia — for immune and thymic regulation and aging.

Read the guide →
Anti-AgingImmuneSkin

Glutathione

GSH, L-Glutathione

The body's “master antioxidant” — a naturally occurring tripeptide central to cellular defense, studied for oxidative stress, immune function, metabolic health, and (controversially) skin lightening.

Read the guide →
Not medical advice. The Peptide Almanac summarizes published research for education only. Full disclaimer →

Frequently asked questions

Do thymic peptides like thymosin alpha-1 boost immunity?

Thymosin alpha-1 is approved in a number of countries (as Zadaxin) for conditions like hepatitis and modulates T-cell function, but it is not FDA-approved in the US. Most other thymic peptides have limited independent evidence and are unapproved research compounds.

Is LL-37 something you can take to fight infection?

No. LL-37 is a natural human antimicrobial peptide, not an approved drug. Its biology is double-edged — it also contributes to inflammatory and autoimmune conditions — so it is a research subject rather than a supplement.

Which immune peptides are actually FDA-approved?

Icatibant (Firazyr), for acute hereditary angioedema attacks, and glatiramer acetate (Copaxone), for relapsing multiple sclerosis, are FDA-approved. Most other peptides in this category are not.

Educational content only — not medical advice. See our Privacy Policy.