This guidance is intended to explain to applicants how the review goals established as part of the Generic Drug User Fee Amendments Reauthorization of 2017 (GDUFA II) apply to amendments to either abbreviated new drug applications (ANDAs) or prior approval supplements (PASs) submitted to the Food and Drug Administration under section 505(j) of the Federal Food, Drug, and Cosmetic Act (FD&C Act) (21 U.S.C. 355(j)).2 This guidance describes amendment classifications and categories and explains how amendment submissions may affect an application’s review goal dates. The guidance also describes how FDA should assess3 amendments submitted to ANDAs and PASs received prior to October 1, 2017, which is the GDUFA II review goals effective date.