FDA's Overreach on Compounded Peptides The FDA has issued warning letters to multiple companies marketing compounded Retatrutide, an investigational drug from Eli Lilly still in Phase II trials. While early studies have shown promising weight loss results, Retatrutide The FDA just put peptides like BPC 157, TB 500, and KPV on the clock. , As a compounding pharmacist, this is literally my world and most people dont understand the regulatory nuance behind what BPC 157 Erectile Dysfunction Study: What the Evidence Actually Shows FDA Sends Warning Letters to More Than 50 GLP 1 Compounders and Manufacturers Wilson Sonsini FDA warning letters target marketers of unapproved weight loss drugs RAPS