Post-Market Studies Lag for Drugs Fast-Tracked By FDA: Study

A new study raises concerns over the fast-track approval process the FDA uses for some new drugs, finding that not only is there less data on the safety of these medications when compared to other drugs when they are first approved, but also finding that promised post-marketing studies meant to make up that knowledge gap are seldom conducted.  

In a report published in the Journal of the American Medical Association (JAMA) on Monday, researchers from the Institute of Safe Medication Practices and Wake Forest’s School of Medicine indicate that drugs approved through the FDA’s expedited approval process undergo less years of clinical testing than other drugs.

In many cases, the FDA required the companies making those drugs to do post-marketing studies, but those studies are often never submitted, completed or even conducted, according to the study.

Researchers looked at data on 20 drugs approved by the FDA in 2008, with 12 of them undergoing the normal review process and eight going through the expedited approval process. The expedited approval track is generally reserved for drugs that the FDA deems fill a pressing need not currently being filled by other drugs on the market.

The researchers found that the expedited drugs only went through 5.1 years of clinical testing, compared to 7.5 years for drugs that went through standard approval processes. Those expedited drugs were tested for efficacy in a median of 104 patients, compared to 580 patients for drugs undergoing standard review.

According to the study, nonclinical testing revealed that six of the drugs were animal carcinogens, five were in vitro mutagens, and 14 animal teratogens (drugs capable of interfering with fetal development) were detected. In addition, when the FDA asked for post-marketing studies to make sure the drugs it had already approved were actually safe to be on the market, the study suggests that few drug makers actually did so.

“The FDA required 85 postmarket commitments,” the study’s authors note. “By 2013, 5 drugs acquired a new or expanded Boxed Warning; 26 of 85 (31%) of the postmarketing study commitments had been fulfilled, and 8 (9%) had been submitted for agency review.”

Expedited Drugs Not The Only Studies Missing

This latest study follows a report published in the same medical journal in July, which found that more than 40% of postmarketing studies for all drugs had not even been started.

That study also indicated that the rate of completion for post-marketing studies that the companies actual start is extremely low. In 2011, only 12% of studies had been completed, a “jump” from the under 7% that had been completed in 2007. The trend for completion has improved since 2007, however the rate of completion still leaves more than 85% unfinished.

Serious side effects associated with prescription drugs are often not discovered until after a medication has been approved and is available on the market, which highlight the importance of drug makers continuing to follow up with studies once the medications are being used by thousands or even millions of people.

A 2006 report from the Office of Inspector General found that drug companies were seriously deficient in completing post-marketing studies and indicated that the FDA lacked the authority to enforce completion. Congress passed the FDA Amendments Act (FDAAA) in 2007, which required post-marketing studies as part of the drug approval process, and offered the FDA more latitude in mandating compliance with completing the studies.

Critics have suggested that the FDA is failing to crack down on pharmaceutical companies, which are flaunting compliance with post-marketing study requirements, noting that issuing warning letters, initiating litigation for “significant failures,” and conducting seizures and injunctions are all within the FDA’s legal power, and pointing out that the agency has made little use of that enforcement power.