FDA Market Approval Process

If a Phase III trial is successful, the evidence is brought to the FDA in a New Drug Application (NDA). Typically, the FDA requires two separate phase III trials to grant approval of a drug.  In rare circumstances where Phase III studies cannot be conducted the FDA may grant approval based on Phase II studies.  The NDA is reviewed by the Oncologic Drug Advisory Committee (ODAC) that consists of nine independent cancer experts.  ODAC members are usually not FDA employees.  They are charged with interpreting the clinical trial efficacy and safety data to make a recommendation to the FDA regarding approval, but the final approval rests with the FDA Commissioner.   Approximately 25% of Phase III drugs submitted by NDA to ODAC become FDA approved for market. 

In the 1980s, the FDA NDA approval process was dismally slow due to lack of staff and a surge in new drugs.  In past cases, the FDA labored 22 months to review NDAs.  In response to the outcry from the AIDS community, Congress passed the Prescription Drug User Fee Act of 1992.  The FDA was then able to hire additional staff by charging pharmaceutical companies a “user fee” of $200,000 leading to FDA review and record approval of priority drugs in 2 months, such as Gleevec in 2001.