Correlates of time to approval and other clinical development periods.

The drug development cycle is classically divided into a clinical phase and review phase, with the clinical phase typically being further partitioned based on the planning and conduct of adequate and well controlled trials. Factors affecting the duration of the development intervals have not previously been systematically investigated. Here, we analyze a large population (N=825) of New Drug Applications (NDAs) approved between 2008 and 2017 to characterize the typical duration of these intervals and the development factors associated with their duration. These data and analyses will help those involved in pharmaceutical development by enabling data-driven planning and by providing insight into the effect of certain factors on the duration of drug development programs.

Identification of factors associated with first-cycle drug approval rates and regulatory outcomes for new drug applications.

The aims of this study were to identify types of deficiencies resulting in delay of approvals for drugs eventually approved by the US FDA and to search for factors associated with higher first-cycle approval rates. Review documents of New Drug Applications approved between 2008 and 2017 were retrieved from the Drugs@FDA database. Basic characteristics of the applications, regulatory actions, and reasons for non-approvals and/or major amendments after first review cycle were investigated. Of 825 applications studied, 446 (54.1%) applications received first-cycle approvals without a review extension resulting from a major amendment. Non-approvals (240, 29.1%) were based primarily on chemistry/manufacturing/controls and safety reasons. A higher first-cycle approval rate was associated with factors related to unmet medical needs or innovative development. The association between higher first-cycle approval rates and innovative drugs or those addressing unmet needs reveals the FDA's commitment in advancing innovation and protecting public health.