Elanco updates U.S. Zenrelia label following FDA review of data

Elanco (ELAN) announced updates to the U.S. Zenrelia label, following FDA review of supplemental scientific data. At launch, the U.S. Zenrelia label included language based on the outcome of a laboratory study of unvaccinated dogs dosed at three times the label dose of Zenrelia. During that study, an outbreak of concurrent diseases occurred, complicating interpretation of the results. Upon evaluation of additionally submitted data, the FDA now concludes that “the totality of evidence supports removal of the risk of fatal vaccine-induced disease from modified live virus vaccines from the labeling,” and this language has subsequently been removed from the Zenrelia label in the U.S. The label boxed warning continues to advise discontinuation of Zenrelia for at least 28 days to three months prior to vaccination and withholding Zenrelia for at least 28 days after vaccination due to the risk of inadequate immune response to vaccines.