FDA Targets GLP 1 and Peptide Compounding, Advertising and 'Research Use Only' Labeling 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 Restoring Balance: What the FDA's Peptide Announcement Could Mean for Patient Access and Safety Empower Pharmacy BPC 157 Weight Loss: Evidence & Safety