Notes from the peptide supplier frontier

Harvard's David Sinclair on GHK-Cu, epitalon, apelin and collagen: what the science shows, what it doesn't, and why the vial still matters.

Retatrutide is not approved anywhere. Lilly files with the FDA in Q1 2027. What the trials show, when it could arrive, and what the TGA found in a vial.

Lilly has filed six federal suits over black-market retatrutide, targeting RUO sellers for the first time. What the filings claim, the scale numbers behind them, and what it means for anyone reading peptide paperwork.

Why we started PepiScreen, what independent supplier screening actually means, and what we'll be writing about here.

A worked-example post showing every editable block you can use — hero, buttons, media, tables, charts, callouts, quotes, lists, columns, CTAs. Duplicate it as a starter for new posts.

The Peptide Guide now covers seventeen compounds. This week we added Tesamorelin, the peptide with the most published human clinical data of anything in the growth-hormone family, and GHK-Cu, the copper-bound tripeptide that dominates cosmetic skincare and shows up increasingly in injection protocols for hair and wound healing.