Warning Letters Are Not New Rules: FDA Enforcement vs Rulemaking on Peptides
Five FDA warning letters to peptide sellers were posted on 1 September 2026. They apply existing law to five named firms. They did not change the rules for anyone else.
Peptide research, quality, and regulatory news.
Five FDA warning letters to peptide sellers were posted on 1 September 2026. They apply existing law to five named firms. They did not change the rules for anyone else.
Four peer-reviewed 2026 reviews assessed BPC-157, TB-500, CJC-1295, MK-677, ipamorelin and GHK-Cu for musculoskeletal use. The most systematic found 67% of the literature is animal research.
A 2026 review in Separation Science Plus surveys peptide analysis methods and names LC–MS/MS the gold standard for quantification. How chromatographic purity, mass-spectrometric identity and stability testing answer different questions.
Boehringer Ingelheim says its investigational GLP-1/GIP/NPY2 triple receptor agonist BI 3034701 has entered Phase II development for obesity. What the company announced, and what a Phase II start does and does not mean.
USP and the European Pharmacopoeia now formally recognise recombinant Factor C for bacterial endotoxin testing, and why endotoxin is a separate result on a COA.
Novo Nordisk filed CagriSema with the FDA in December 2025 and says a decision is anticipated by late 2026. What the REDEFINE trials showed, and what REDEFINE 4 did not.
Retatrutide’s first Phase 3 type 2 diabetes trial, TRANSCEND-T2D-1, was published in The Lancet and presented with TRIUMPH-1 obesity data at ADA 2026.