This bill, known as "Leo's Law," aims to mitigate the adverse effects of the COVID-19 pandemic on the development of orphan drugs by extending various market exclusivity periods and certain patent-related approval-delay periods by 180 days . These extensions are intended to compensate for potential disruptions and delays experienced by developers during the public health emergency. The legislation specifically targets " covered orphan drugs ," which are defined as orphan drugs for which an investigational new drug application was submitted during the COVID-19 emergency period , starting December 1, 2019. To qualify, the drug must also have received subsequent approval and have no approved indications for non-rare diseases. The extended periods include the 12-year exclusivity for biologics, the 5-year and 3-year exclusivities under the Federal Food, Drug, and Cosmetic Act, and the 7-year orphan drug exclusivity, along with conforming extensions for related periods. This measure seeks to preserve incentives for companies developing treatments for rare diseases.