The Food and Drug Administration (FDA) oversees the safety and effectiveness of drugs sold on the U.S. market. When there is an unmet need for the treatment of a serious condition, FDA may use one or more of its expedited programs, such as fast track and breakthrough therapy designation, which are intended to bring drugs to market more quickly. FDA is also responsible for monitoring the safety of drugs and reporting on those efforts. This book examines the number and types of requests for fast track or breakthrough therapy designation; the number and types of FDA-approved drug applications that used an expedited program; and the extent to which FDA's data on tracked safety issues and postmarket studies allowed the agency to meet its reporting and oversight responsibilities.