Under the Prescription Drug User Act the FDA created a two-tiered system for review of new drug applications (NDA). The first tier of this system, known as Standard Review, is for treatments that offer a minor improvement over existing therapies, and sets the timeline to review at 10 months from receiving the NDA. The second tier, the Priority Review, is for drugs that offer major advances over existing therapies, or provide a treatment where none had previously existed, and reduces the approval timeframe of review to 6 months.
Significant improvements over pre-existing treatments include evidence of increased effectiveness in treatment, prevention, or diagnosis, reduction in treatment-limiting reactions, evidence of safety and effectiveness in a new patient population, and documented enhancement of patient compliance that is thought to lead to an improvement in serious outcomes.
Unlike other expedited approval programs with different levels of standards the Priority Review designation does not change the scientific or medical standards used for approval by the FDA. Instead more resources are devoted to expediting approval for the treatments that receive this designation because the FDA has decided chosen treatments serve a much greater need. To receive the Priority Review designation the FDA requires evidence of increased effectiveness in treatment prevention, or diagnosis of a condition.
Previous Entries in the Primer Series
The FDA Approval Process
The FDA Breakthrough Therapy Designation
THE FDA Accelerated Approval Designation
New Developments in Lymphoma 