Every major therapeutic peptide covered in depth. Mechanism, evidence tables, safety, regulatory status, and Design Lab links.
This encyclopedia covers 40 therapeutic and research peptides across eight categories — from FDA-approved drugs like semaglutide and tirzepatide to compounded peptides like BPC-157 and thymosin alpha-1. Each entry includes the peptide's molecular structure and amino acid sequence, detailed mechanism of action with signaling pathways, a clinical evidence table with study-level ratings, safety profile and known adverse effects, current regulatory status across major jurisdictions, and a link to analyze the sequence in our interactive Design Lab.
Peptides are short chains of amino acids — typically between 2 and 50 residues — that function as the body's molecular messengers. They regulate everything from blood sugar (insulin) and appetite (GLP-1 agonists) to immune defense (thymosin alpha-1, LL-37) and tissue repair (BPC-157, TB-500). As of 2026, over 100 peptide drugs have been approved by the FDA, and the global peptide therapeutics market exceeds $50 billion annually. For a foundational overview of what peptides are and how they work, see our complete beginner's guide.
The peptide landscape is evolving rapidly in 2026. The FDA's anticipated reclassification of 14 previously restricted peptides back to Category 1 status is restoring legal compounding access for compounds like BPC-157, thymosin alpha-1, and Selank. At the same time, next-generation obesity peptides like retatrutide (a triple GLP-1/GIP/glucagon agonist achieving up to 28.7% weight loss in trials) and cagrilintide (being developed as CagriSema in combination with semaglutide) are advancing through clinical trials. For the latest regulatory updates, see our March 2026 intelligence briefing.
Every entry in this encyclopedia is written for clinicians, pharmacists, researchers, and informed patients. We provide honest evidence ratings — distinguishing between peptides with robust Phase III RCT data (like semaglutide) and those with strong preclinical data but limited human trials (like BPC-157). We believe accurate evidence assessment is as important as the science itself. All content is written by the PeptideBond editorial team and updated regularly.