FDA Adverse Event Reporting More Accurate Than Once Thought: Study

New research suggests that reports of problems associated with prescription medications submitted to the FDA Adverse Event Reporting System (FAERS) may be more accurate in tracking drug side effects than previously thought.

In a report published in Drug Safety, researchers looked for signs of what is known as the “Weber Effect” in FAERS reports, which suggests that side effect reports for drugs peak during the first two years.

This has generally led to the belief that adverse event reports are not accurate indicators of the prevalence of potential side effects, but rather are an artifact of attention being placed on the new drug. Some observers have estimated that only about one-in-ten adverse events are actually reported to FAERS.

For years, the FDA has been attempting to make FAERS more accurate and to increase participation. The new study suggests that the efforts are working.

Researchers looked at reports involving 62 drugs approved by the FDA between 2006 and 2010.

“While a few of the drugs demonstrated what could be considered ‘Weber effect’ curves, a majority of the drugs showed little evidence for the effect,” the researchers determined. “In fact, the general AE reporting pattern observed in this study appears to consist simply of increasing case counts over the first three quarters after approval followed by relatively constant counts thereafter.”

The researchers concluded that most modern adverse event reporting does not have the Weber effect pattern, due to efforts that have led to large increases in FAERS reports and a “concerted effort by the FDA to increase awareness regarding the utility of post-marketing AE reporting.”

Adverse Event Reports Can Signal Serious Drug Problems

Voluntary adverse event reports submitted to the FDA have been used to track and discover a number of significant risks associated with medications after they were approved in recent years.

Concerns over bleeding events linked to the relatively new blood thinner Pradaxa first garnered attention due to the large number of adverse event reports submitted to FDA regarding the drug. The Institute of Safe Medication Practices (ISMP), which relies heavily on FAERS analyses for its drug safety profiles, noted in October 2011 that hundreds of adverse event reports had been linked to Pradaxa bleeding events.

At the time the drug was just one year old, but it ended up leading all other drugs in the number of adverse events reported, with thousands of reports of uncontrolled bleeding and hundreds of deaths. ISMP noted that there were more consumer complaints for Pradaxa during the first three months of its release than 98.7% of all other drugs ISMP monitored.

Several thousand Pradaxa lawsuits have since been filed by individuals who claim that serious and sometimes fatal bleeding problems were caused by the manufacturer’s failure to warn doctors and patients that there was no reversal agent to stop the drug’s blood thinning effects, resulting in doctors being unaware of how to treat Pradaxa bleeding events.

Other problems first noticed by looking at FAERS reports were Chantix psychological problems, which also lead to thousands of lawsuits, and became a cultural touchstone. The violent and suicidal urges linked to the drug became well known, as did so-called Chantix Nightmares; vivid, frightening dreams associated with the smoking cessation drug.

Last year, the FDA issued a warning that Tylenol can cause dangerous skin rashes, known as Stevens-Johnson Syndrome (SJS) which can cause the skin to fall off and can be fatal in some cases. The agency noticed a number of FAERS reports on the side effect, setting off red flags at the agency.

Despite those cases, many researchers and drug companies express concern when studies revealing drug side effects rely on FAERS reports, due to its unscientific means of collecting data and its voluntary reporting structure.