FDA's Legislative Request on Rx and Compounded Drug Advertising Coalition for Healthcare Communication 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 U.S. Food and Drug Administration is moving toward allowing compounding pharmacies to produce more than a dozen injectable peptides that were banned because of potentially significant safety risks, the New York FDA Sends 30 Warning Letters To Continue Clampdown on Compounded GLP 1s BioSpace