The report, released yesterday in the journal Archives of Internal Medicine, suggests the existing safety system "is not adequately protecting patients" and illustrates the "need for improved systems".
According to the report, there was a total of 467,809 serious adverse drug events (ADEs) reported to the US Food and Drug Administration (FDA) between 1998 and 2005.
The annual number of reports increased 2.6-fold over the period from 34,966 to 89,842.
Meanwhile, the number of deaths associated with serious ADEs increased 2.7-fold from 5,519 to 15,107, and serious ADEs from biotechnology products jumped 15.8-fold from 580 to 9181.
"It ought to be cause for great concern," report author Thomas Moore told US-PharmaTechnologist.com.
"We are discovering large numbers of adverse events that are more serious or not discovered during the original licensing. That says we need to run a tighter system."
A serious ADE, as defined by the FDA, means an adverse event that resulted in death, a birth defect, disability, hospitalization, or was life threatening or required intervention to prevent harm.
Such events are voluntarily reported to the FDA through its Adverse Event Reporting System (AERS) known as MedWatch reports.
Moore said the majority of the events reported were "new and unexpected" which were not listed on the drugs labeling, and the incidence of events could be higher than that published in the report due to the voluntary nature of AERS.
Moore put the increase down to three possible reasons: an increase in prescriptions driven by an aging population; an increased market presence of biotechnology products; and a marked increase in the number of deaths and injuries associated with drugs that had been used for years.
"Contrary to our expectations, drugs related to safety withdrawals were a modest share of all reported events and declined in importance over time [from 26 per cent of reported events in 1999 to 1 per cent in 2005]," the report said.
"Among the most frequently reported drugs associated with fatal events, we observed a disproportionate contribution of pain medications and drugs that modify the immune system," the report continued.
The top drugs most frequently identified in fatal and non-fatal serious events were the opioid analgesic oxycodone and the hormone estrogen respectively.
While Moore said all drugs had risks, he said "there's enough blame to go around" for what he suggested was a shoddy safety system where the "testing of drugs and safety evaluation needed to be tightened".
"The Pharmaceutical industry has opposed improving the drug safety system for years. It's clear the FDA and European requirements for drug approval are not finding adverse events, doctors are not paying enough attention to adverse events, and patients are not getting enough information," he said.
"The results highlight the importance of this public health problem and illustrate the need for improved systems to manage the risks of prescription drugs," the report concluded.
Currently, new drugs are approved by the FDA based on the clinical data provided to the agency which is reviewed by a team of experts that evaluate whether the studies show that the drug is safe and effective for its proposed use.
"No drug is absolutely safe; all drugs have side effects. 'Safe' in this sense means that the benefits of the drug appear to outweigh the risks. If the FDA decides that the benefits of a drug outweigh the risks, the drug will receive approval and can be marketed in the United States," the FDA website said.
According to a statement released by the FDA in response to the report, "[the] FDA's office of surveillance and epidemiology is aware of the increasing numbers of adverse event reports, and we take them seriously".
"We have undertaken a pilot program to review the safety of new molecular entities about 18 months after approval. We will determine if this formal, systematic review adds value to our current process . . . We are working on an updated version of our current adverse event database, which will have improved functionalities for more efficient adverse event detection and analysis."
The FDA currently devotes half of its pharmaceutical review budget to product safety.
Pharmaceutical Research and Manufacturers of America (PhRMA) senior vice president Ken Johnson said in a statement: "Ensuring the safety and effectiveness of prescription medicines through continuous research is a core commitment of America's pharmaceutical research companies. Recognizing that not all safety issues can be determined through the development phases of a drug, the adverse event reporting system is a valuable tool for detecting unforeseen risks associated with potentially lifesaving medicines.
"Although there is always room for improvement, the US has the world's best drug safety record," he said.
The FDA and pharmaceutical companies were continually looking at ways to improve adverse reaction detection, he said.
