Expedited FDA reviews examined in new study

Of the drugs approved by the FDA in 2008, those that received expedited reviews were approved more quickly, were studied in fewer patients and still have unanswered safety questions, according to new data published in JAMA Internal Medicine.

“Under the Obama administration, the FDA may also change the testing requirements for many drugs prior to approval; the stated rationales are promoting innovation and reducing the time and cost of discovering new drugs,” researchers wrote. “To inform the debate about the appropriate standards for testing new drugs, we studied the development times, clinical testing, postmarket follow-up, and safety risks for the new drugs approved by the FDA in 2008, when most provisions of current law, regulation, and policies were in effect.”

Of the 20 therapeutic drugs approved by the FDA in 2008, eight received expedited review and 12 received standard review. Data showed that expedited drugs obtained marketing approval within a median of 5.1 years vs. 7.5 years for standard review drugs (P=.05).

In terms of testing, efficacy was studied in a median of 104 patients receiving the active drug for drugs that underwent expedited review vs. 508 patients for drugs that underwent standard reviews (P=.003). According to study results, 25% of all 20 drugs were tested for efficacy in a single trial, 55% had two trials and four drugs were tested in more than two trials. However, none of the expedited drugs was tested in more than two trials, according to the researchers, and three were approved based on efficacy data from a single trial.

Nonhuman studies indicated that six drugs were animal carcinogens, five were in vitro mutagens and 14 were animal teratogens, and no pre-approval trials lasted longer than 24 weeks. Safety concerns resulted in five boxed warnings and risk management plans for eight of the drugs. By 2013, five drugs acquired a new or expanded boxed warning.

Overall, the FDA required 85 postmarketing studies for 19 of the 20 drugs, but by 2013, only 26 of these study commitments had been fulfilled and eight had been submitted for review.

In an accompanying commentary, Daniel Carpenter, PhD, of Harvard University, said this study emphasizes the importance of well-conducted premarket studies as well as provides reason to be cautious when deciding which drugs require expedited review.

“If the FDA’s requirements for new drugs, both premarket and postmarket are weakened, trust in both the efficacy and safety of prescription drugs is likely to be weakened. The stakes of the current policy debates could not be higher. There is scarcely a feature of the American health care system that does not depend on evidence-based trust in prescription drugs, ratified and enforced by the FDA,” Carpenter wrote.

For more information:

Carpenter D. JAMA Intern Med. 2013;doi:10.1001/jamainternmed.2013.9202.

Moore TJ. JAMA Intern Med. 2013;doi:10.1001/jamainternmed.2013.11813.

Disclosure: The researchers report no relevant financial disclosures. Carpenter reports no relevant financial disclosures.