FDA requirements for postmarket data on new prescription drug approvals have raised the number of postmarket studies completed and reduced the number of uninitiated studies by manufacturers, researchers found.
Following the passage of the Food and Drug Administration Amendments Act (FDAAA) in 2007, the number of completed studies that fulfilled postmarket obligations nearly doubled from 6.6% in 2007 to 12.6% in 2011, according to G. Caleb Alexander, MD, of Johns Hopkins University, and colleagues.
Among studies not yet initiated by the manufacturer, there was an opposite trend over the study time period, with 56.7% studies not started in 2007 and 43.5% not yet started in 2011, they wrote in a research letter online in the Journal of the American Medical Association.
"Our analysis found the number of studies not yet started declined during this 5-year period, and the number of studies fulfilling obligations nearly doubled," the authors pointed out.
Prior to 2007, drug manufacturers completed postmarket safety trials on a voluntary basis. The passage of the FDAAA authorized the agency to require manufacturers to submit postmarket data as part of the prescription drug approvals process, as well as holding manufacturers to deadlines.
Many rare, but potentially serious adverse events are only found after a drug receives FDA approval, the authors noted.
The study reviewed changes in fulfillment of postmarket studies following the passage of the FDAAA from 2007 to 2011 through a review of all postmarket study status data for both biological and new drug applications.
Studies were categorized as pending, ongoing, delayed, terminated, submitted, released, and fulfilled.
The total number of postmarketing studies in each year in the study period was greater than the number required under the act:
- 1,841 versus 0 required in 2007
- 1,901 versus 46 in 2008
- 2,227 versus 153 in 2009
- 1,774 versus 279 in 2010
- 1,781 versus 387 in 2011
The authors noted three trends over that time: the number of studies not yet started decreased, completed studies that met postmarket requirements increased, and delayed studies also increased. The number of studies not yet started fell from 1,044 (56.7% of all studies) in 2007 to 775 (43.5%) in 2011. Completed studies rose from 122 (6.6%) in 2007 to 224 (12.6%) in 2011. Delayed studies rose from 125 (6.8%) in 2007 to 241 (13.5%) in 2011.
Over the study period, the number of ongoing studies, studies submitted for FDA evaluation, and terminated studies remained relatively constant.
"These trends help address concerns expressed by the Institute of Medicine that many postmarketing studies before the FDAAA were not implemented or fulfilled," they wrote, cautioning that in spite of improvements, "more than 40% of studies had not yet been started in 2011," while the number of studies that were delayed doubled over the study period to "approximately one in eight."
The authors also noted that their research was limited by a design that did not statistically isolate the legislation's effect on fulfillment rates, and a lack of examination of content and outcomes of postmarketing studies.
The study was supported by the Agency for Healthcare Research and Quality.
The authors declared support from the FDA and IMS Health.
Journal of the American Medical AssociationSource Reference: Alexander GC, et al "The Food and Drug Administration Amendments Act and postmarketing commitments" JAMA 2013; 310: 202-203.