The U.S. Food and Drug Administration has asked Eli Lilly for more data on liver injury linked to its newly approved obesity pill, according to a letter posted on the health regulator's website.
The weight-loss pill, branded Foundayo, won approval earlier this month under the Commissioner's National Priority voucher program, which aims to speed FDA decisions on drugs deemed critical to public health or national security.
The letter, which was signed on April 1, also said Lilly must conduct post-marketing trials to assess risks related to cardiovascular events and delayed gastric emptying.
It also asked the drugmaker to conduct a milk-only lactation study in lactating women who have received a dose of the pill to assess concentrations of the drug in breast milk using a validated assay.
The drugmaker and the Department of Health and Human Services, which oversees the FDA, did not immediately respond to Reuters requests.
Lilly is already conducting a trial comparing the pill with insulin glargine in participants with type 2 diabetes and obesity who are at increased cardiovascular risk.
The FDA also asked Lilly to run a trial using ultrasound to measure the effects of temporary treatment interruption and fasting duration on retained gastric contents, to evaluate delayed gastric emptying associated with the class of drugs known as GLP-1s.
The once-daily oral medication, which targets the GLP-1 hormone, helped patients lose between 12% and 15% of their body weight in trials.
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