Vioxx was available for five years before being removed due to concerns over increased risk of cardiovascular problems.

Now, the Institute of Medicine (IOM) has issued a report concluding that the US Food and Drug Administration (FDA) still does not have the capacity to adequately track the safety of new medications or to respond fast enough to problems when they emerge. The FDA commissioned the study.

The agency needs better funding, more staff and greater authority to monitor the safety of drugs already on the market, says the report, and a more effective system of labeling and marketing new drugs is necessary to properly inform the public about safety caveats that may come along with approval.

New drugs should be required to carry a special symbol informing patients and doctors that uncertainties may remain about their risks and benefits for two years following their approval, the IOM recommends. Further, it would be advisable to place restrictions on advertising during that period, the report adds.

A safety review should be conducted by the FDA five years after approval of a drug as a matter of routine, the IOM suggests, which would essentially place new drugs on a probationary status.

"As the science of drug development continues to evolve, we must constantly improve the approach to drug regulation to ensure that care providers and patients can make optimal decisions about the medicines they use to improve their health," says the FDA in response to the findings.

"I am committed to taking additional steps and will look to the initiatives recommended by the Institute of Medicine to ensure we continue to fulfill our mission," comments FDA Acting Commissioner Andrew von Eschenbach. "Over the next months, you will be hearing extensively from us about these new endeavors."