Disclosure: We earn a commission from vendors on this page. Rankings are based on price, COA availability, and reputation.

Best Immune Peptides (2026)

Immune peptides strengthen your body's defense systems — from T-cell activation to antimicrobial action. Here are the best vendors for each.

At a Glance

1

Gold standard immune peptide. FDA orphan drug for hepatitis B. Activates T-cells and dendritic cells. Well-tolerated even long-term.

Gold standard immune peptide. FDA orphan drug for hepatitis B. Activates T-cells and dendritic cells. Well-tolerated even long-term.

VendorPriceAmount$/mgCOA
EZ Peptides$85.0010mg$8.50/mgYesBuy →
Limitless Biotech$67.9910mg$6.80/mgYesBuy →
Ascension Peptides$70.0010mg$7.00/mgYesBuy →
See all Thymosin Alpha-1 vendors →
2
KPV3 vendors

Potent anti-inflammatory tripeptide derived from alpha-MSH. Strong gut and skin inflammation data. Very few side effects.

Potent anti-inflammatory tripeptide derived from alpha-MSH. Strong gut and skin inflammation data. Very few side effects.

VendorPriceAmount$/mgCOA
EZ Peptides$45.0010mg$4.50/mgYesBuy →
Ascension Peptides$50.0010mg$5.00/mgYesBuy →
Limitless Biotech$48.995mg$9.80/mgYesBuy →
See all KPV vendors →
3
LL-373 vendors

Natural antimicrobial peptide — kills bacteria, viruses, and fungi directly. Also modulates immune response.

Natural antimicrobial peptide — kills bacteria, viruses, and fungi directly. Also modulates immune response.

VendorPriceAmount$/mgCOA
Limitless Biotech$67.505mg$13.50/mgYesBuy →
Limitless Biotech$67.505mg$13.50/mgYesBuy →
Limitless Biotech$67.505mg$13.50/mgYesBuy →
See all LL-37 vendors →
4

Thymus hormone that matures T-cells. Age-related decline makes supplementation logical but limited modern research.

Thymus hormone that matures T-cells. Age-related decline makes supplementation logical but limited modern research.

No vendors currently in stock.

5
VIP1 vendor

Vasoactive intestinal peptide — broad anti-inflammatory. Used in CIRS/mold illness protocols. Complex dosing.

Vasoactive intestinal peptide — broad anti-inflammatory. Used in CIRS/mold illness protocols. Complex dosing.

VendorPriceAmount$/mgCOA
Limitless Biotech$64.995mg$13.00/mgYesBuy →
See all VIP vendors →

How We Rank Vendors

Every vendor is scored on three factors: price per mg (40%), third-party COA testing (30%), and community reputation (30%). Scores floor at 8.0 — if a vendor is on our site, they are worth buying from.

Price (40%)

Normalized to $/mg for fair comparison across vial sizes.

COA Testing (30%)

Third-party lab results confirming purity and identity.

Reputation (30%)

Community feedback, shipping reliability, and track record.

Peptides A–Z

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