A new JAMA study finds that one in three novel therapeutics approved by the FDA between 2001 and 2010 have safety risks detected only after they were approved. The study authors make a compelling case that to ensure patient safety the FDA should be monitoring drugs throughout their lifetime. Often safety issues do not arise until several years after drugs are approved.

For the study, the researchers analyzed 222 novel therapeutics, including 183 pharmaceuticals and 39 biologics). Most of them were for the treatment of cancer, hematology and infectious disease. Three of the drugs were taken off the market. The FDA acted to address drug safety issues for 71 (32 percent) of them, in many cases as much as four years or longer after their approval. In 61 cases, the FDA required serious “black box” warnings on the packaging for the drugs.

The FDA only approves drugs that are found to be safe and effective, generally based on clinical trials. But, the Washington Post reports that often relatively few patients are involved in these trials, and these patients are not representative of the general population. Safety issues often arise only after large numbers of people take the medications.

Typically, it took 4.2 years from FDA approval for the detection of the new risk for the novel drug. In the case of one of the withdrawn drugs, efalizumab, it took 5.4 years from approval to withdraw it from the market. Because it can take so long from FDA approval to understand the safety risks of new therapeutics, it is generally advisable to try all other treatments that have been on the market for a substantial period of time before taking a novel therapeutic drug or biologic.

Speeding up the drug approval process will only make it more important for the FDA to assess the benefits and risks of drugs after they are approved as well as to find ways to let people know about safety issues as quickly as possible. The researchers found the greatest number of safety issues among the drugs approved most quickly–under a speedy approval process–along with biologics and drugs that treat psychiatric disease.

To best ensure patient safety, the FDA should collect data on the safety of drugs post approval from all patients using them.