The letter, based on Lilly's testing of samples of compounded products, is the company's latest move against drug compounders it says are marketing illegal copies of Zepbound and its diabetes drug Mounjaro. "FDA (the U.S. Food and Drug Administration) warns that compounded products can be risky for patients because they are not reviewed for safety, effectiveness, or quality. Adding a reactive substance like vitamin B12 without clinical testing or FDA review introduces additional unknown risks," said David Hyman, Lilly's chief medical officer. Lilly said it notified the FDA of its findings and called for a nationwide recall of products containing both ingredients. The FDA in September issued warning letters to 30 telehealth companies for making false or misleading claims about compounded versions of weight-loss drugs.

Source: The Telegraph March 12, 2026 10:18 UTC