What is the difference between LL-37 and PDA?

LL-37 (Cathelicidin LL-37) is graded B and is Not FDA-approved — endogenous antimicrobial peptide; clinical trials for infected wounds. PDA (Pentadeca Arginate (PDA)) is graded C+ and is Not FDA-approved — newer compounded analog of BPC-157. They are commonly compared because they share the categories: anti-inflammatory.

Which has stronger clinical evidence — LL-37 or PDA?

On our internal evidence scale, LL-37 is B and PDA is C+. A+ indicates large RCTs plus FDA approval; C indicates primarily preclinical or anecdotal evidence.

What is the typical dose of LL-37 vs PDA?

LL-37: Trial range: topical or intralesional. PDA: 200–500 mcg daily (subcutaneous). Always work with a licensed clinician — peptide dosing should be individualized.

LL-37 vs PDA

Both LL-37 and PDA are used for anti-inflammatory. Here's how their evidence, dosing, and regulatory status actually compare.

LL-37

Evidence B

Cathelicidin LL-37

The only human cathelicidin antimicrobial peptide. Active against bacteria, viruses, and biofilms. Investigated topically for infected wounds and mucosal infections.

View full LL-37 profile →

PDA

Evidence C+

Pentadeca Arginate (PDA)

A 15-amino-acid arginate analog developed as a more stable, sometimes more bioavailable alternative to BPC-157. Limited published research; popular among compounding pharmacies in 2025–2026.

View full PDA profile →

Side-by-Side

Attribute	LL-37	PDA
Evidence Grade	B	C+
FDA Status	Not FDA-approved — endogenous antimicrobial peptide; clinical trials for infected wounds	Not FDA-approved — newer compounded analog of BPC-157
Typical Dose	Trial range: topical or intralesional	200–500 mcg daily (subcutaneous)
Clinics Indexed	19	41
Categories	immune, anti-inflammatory	recovery, anti-inflammatory

Key reported benefits — LL-37

✓Broad antimicrobial activity
✓Wound healing
✓Anti-biofilm

Key reported benefits — PDA

✓Tissue repair
✓Anti-inflammation
✓Potentially better stability than BPC-157

Educational use only

This comparison is for educational purposes and not medical advice. Peptide selection should be made with a licensed medical professional based on your individual goals, health history, and current evidence quality.

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