Research Guides

The short answer Cagrilintide is a synthetic, long-acting analogue of human amylin, developed by Novo Nordisk. It is not an FDA-approved drug on its own. Novo Nordisk filed for FDA approval in December 2025, but that filing is for a fixed-dose combination product called CagriSema, not for cagrilintide by itself. As of this writing, cagrilintide…

Research use only. Peptides supplied by Peptryn are sold strictly for in vitro and preclinical laboratory research. They are not approved by the FDA for human or veterinary use, and nothing here is medical advice, a dosing recommendation, or an instruction for self-administration. This guide summarizes the published record and what regulators have said about…

The short answer Published trial data puts retatrutide’s half-life at approximately 6 days. That figure comes from the Phase 2 trial results Eli Lilly published in the New England Journal of Medicine in 2023, the same study that first reported retatrutide’s pharmacokinetics in detail. What half-life means Half-life is a pharmacology measurement, not a usage…

The one-line answer Semaglutide and tirzepatide are FDA-approved drugs. Retatrutide is not approved anywhere and remains an investigational compound in clinical trials. That single difference in regulatory status is the most important thing to understand before comparing anything else about the three. Approval status and brand names Compound Status Approved brand names Developer Semaglutide FDA-approved…

The short answer Retatrutide is not FDA-approved. It is an investigational peptide, meaning it is still going through the clinical trial process the FDA requires before any drug can be sold for human use. Eli Lilly, the company developing it, said on July 23, 2026 that it plans to file an approval application with the…

BPC-157 explained: what it is, what animal and human studies show, half-life, FDA and WADA status, and five checks for a vial’s certificate of analysis.

Popular peptides ranked by US search volume, with FDA status and what the evidence shows for tirzepatide, retatrutide, CJC-1295, MOTS-c, SS-31 and more.

Buying retatrutide for research? See what a real COA shows, the identity and purity checks, published quality data on online vials, and red flags.

Peptide testing explained: the tests in a full panel (purity, identity, quantity, endotoxin, sterility, metals), sampling, and how to judge a testing lab.

Peptide purity explained: what 99% HPLC purity means, how it differs from peptide content, what the other 1% is, and what EU rules say about limits.