Tufts Study Reveals Mixed Results on Postmarketing Studies

While the number of postmarketing studies for newly approved drugs have increased during the past six years, drug developers feel that the results offer little to their understanding of safety, efficacy, or quality, according to a recently completed assessment by the Tufts Center for the Study of Drug Development. The Tufts CSDD survey found that 68% of clinical study sponsors and 79% of nonclinical study sponsors said results contributed either marginally or not at all to their understanding of the safety, efficacy, or quality of their product. However, 32% said clinical studies significantly or very significantly increased their understanding of their products.

“A lot of progress has been made in the area of postapproval studies since 2001, when the FDA regulation requiring sponsors to provide annual reports on the status of postmarketing studies went into effect,” said Tufts CSDD associate director Christopher Paul Milne. “But a major challenge drug sponsors face is completing the studies on time.”

The study found that more than half of all postmarketing studies submitted were finished by their projected completion date, but 45% were delayed due to enrollment problems, technical difficulties, additional FDA requirements, or sponsors expanding the scope of their studies.

The Prescription Drug User Fee Act (PDUFA), which authorizes the FDA to request postmarketing study reports, is due for renewal in Congress later this year.

The analysis also found that: clinical studies took approximately 10 months longer to complete and cost nine times as much as nonclinical studies; postmarketing studies are typically the responsibility of applicable R&D departments and not marketing departments, as some PDUFA critics claim; and between 1998 and 2005 sponsors spent approximately $5.3 million per postmarketing study, compared to $610,000 per nonclinical study.