A brief history of 180-day exclusivity under the Hatch-Waxman Amendments to the Federal Food, Drug, and Cosmetic Act.

This article summarizes the history of the 180-day exclusivity provision on the Hatch-Waxman Amendments to the Federal Food, Drug, and Cosmetic Act (FDCA). Part II presents the statutory language, as amended in the Medicare Prescription Drug, Improvement, and Modernization Act of 2003 (MMA), and summarizes the law that applies to new abbreviated new drug applications (ANDAs) (those filed after December 8, 2003, provided there was no paragraph IV certification to the listed drug prior to December 8), as well as the law that applies to all other ("old") ANDAs. Part III describes the legislative history of the original 1984 provision and traces its judicial and administrative history through the present. Part IV describes the history of the 2003 amendments and describes the key changes made in 2003. While Congress addressed in 2003 a number of the interpretive issues that had arisen since 1984, the new law is intricate and undoubtedly will give rise to new interpretive questions in the months and years ahead.