Streamlining nonclinical drug development using the FDA 505(b)(2) new drug application regulatory pathway

In the USA, drugs are approved by the FDA by three main regulatory pathways: (i) 505(b)(1) new drug applications (NDAs); (ii) 505(b)(2) NDAs; and (iii) 505(j) abbreviated NDAs (ANDAs). The appropriate pathway depends on the active ingredient, already approved drug products, drug formulation, clinical indication, route of exposure, among other factors. The 505(b)(2) NDA pathway is a regulatory approval pathway that allows sponsors to use existing public data in lieu of conducting studies; thus, potentially offering significant drug development and marketing advantages. Nonclinical testing programs for 505(b)(2) submissions are often reduced and, in some cases, are not even required. This paper provides an overview of the 505(b)(2) regulatory pathway with a focus on how nonclinical programs can be streamlined and accelerated.