On April 19, 2026, the U.S. Food and Drug Administration (FDA) issued a formal request for Eli Lilly and Company to provide supplemental data concerning the safety profile of Foundayo, the firm's newly approved oral weight-loss treatment. The regulatory agency’s inquiry specifically targets three areas of clinical concern: potential drug-induced liver injury, cardiovascular safety outcomes, and the physiological impact on gastric emptying. This request follows the initial approval of the drug, which was positioned as a non-injectable alternative to existing GLP-1 receptor agonists.
The FDA’s communication outlines the necessity for a dedicated post-marketing study to evaluate the incidence of elevated liver enzymes among patients using Foundayo. While Phase 3 clinical trials involving over 3,000 participants did not show a statistically significant increase in severe hepatotoxicity, the agency noted a subset of patients with transient elevations in alanine aminotransferase (ALT) levels. Additionally, the FDA has asked for a more granular analysis of cardiovascular events, including heart rate variability and blood pressure fluctuations, over an extended two-year observation period.
Beyond metabolic and cardiac concerns, the regulator is seeking data on the drug’s effect on gastric motility. Because Foundayo belongs to the class of small-molecule GLP-1 receptor agonists, its mechanism of action involves slowing the rate at which the stomach empties. The FDA is investigating whether this effect persists or intensifies with long-term oral administration. Furthermore, Eli Lilly is now required to conduct a clinical lactation study to determine if the active pharmaceutical ingredients in Foundayo are excreted in human breast milk and to assess any potential risks to nursing infants.
In an official statement released Sunday, Eli Lilly confirmed its intent to comply with the FDA’s requests. Dr. Daniel Skovronsky, the company’s Chief Scientific Officer, stated that the firm remains confident in the benefit-risk profile of the medication. The company noted that the requested data will be gathered through ongoing Phase 4 observational studies and a newly commissioned registry. Eli Lilly has committed to providing an interim report on the liver safety data by the fourth quarter of 2026, with the full cardiovascular and lactation results expected by mid-2027.
Foundayo was approved earlier this year following clinical trials that demonstrated an average weight loss of 14.7% over 36 weeks at the highest dosage of 45mg daily. The drug represents a significant shift in the obesity treatment landscape, which has been dominated by injectable medications like tirzepatide. Eli Lilly has invested approximately $1.2 billion in the development and manufacturing scale-up for Foundayo. The FDA’s request for additional data is part of a broader regulatory trend of heightened surveillance for the rapidly expanding class of metabolic and weight-loss drugs.