LL-37

Overview

Natural antimicrobial peptide that provides broad-spectrum defense against pathogens.

Reported benefits

Antimicrobial activity, immune modulation, wound healing, anti-inflammatory

Protocols & dosing

Typical dosage: 2-5 mg (twice weekly).

Detailed dosing protocols have not yet been catalogued.

FDA & legal status

LL-37 is not currently FDA-approved for any indication. Effective April 22, 2026, the FDA removed LL-37 from Category 2 of its Section 503A bulk drug substances list after the original nominators withdrew their nominations. This removal lifts the prior “significant safety risk” designation but does not place LL-37 on the 503A Bulks List. Compounding pharmacies may prepare it with a valid physician prescription and pharmaceutical-grade API from an FDA-registered manufacturer. The FDA’s Pharmacy Compounding Advisory Committee (PCAC) is scheduled to review this substance at its July 23–24, 2026 public meeting. Removed from FDA Category 2 effective April 22, 2026. NOT selected for July 23-24, 2026 PCAC meeting. Deferred to second PCAC meeting before February 2027. NOT currently on 503A Bulks List — requires physician Rx. Source: FDA Advisory Committee Calendar / Lengea Law, May 2026.

Vendor information

PeptideSciences101 does not endorse vendors. For transparency metrics and third-party testing notes, see the vendor directory.

Side effects & safety

Reported side effects: Generally safe, minimal side effects

References

No external sources have been catalogued for this article yet.