Risks of Biologic Drugs
Posted by medconsumers on December 1, 2008
New Concerns About a Class of Drugs Called Biologics
The fastest growing class of new drugs in the U.S. is the so-called biologics. Although the first in this class of drugs was approved in 1982, most have been marketed for a decade or less and little information was available about their safety. A team of Dutch researchers set about to address this important knowledge gap and their findings were recently published in the Journal of The American Medical Association.
Their findings? Almost one in four new biologics approved in the US and/or the EU between 1995 and 2007 had safety problems serious enough to require regulatory action after their approval. The term biologics (also known as biologicals) refers to drugs derived from living material, which can be human, plant, animal or microorganism in origin. Production of biologics is considered to be much more complex than that of traditional drugs. According to the Dutch researchers, “small differences and changes in the production process can therefore have major [safety] implications.” Examples of popular biologics include Enbrel and Remicade for rheumatoid arthritis, Tysabri for multiple sclerosis and Avastin and Herceptin for cancer.
While no biologic has been withdrawn, 19 were found to have had safety problems severe enough for regulators to require black box warnings on the labeling. Adverse events include life-threatening infections, acute hypersensitivity reactions and worsening heart failure—among others. Most of the regulatory actions were taken between 3 ½ and 5 years after approval.
There are some important overall lessons to be learned from this study. First, the data lends supports to the advice that, if better-understood treatments are available, a newly approved drug should be used with extreme caution, if at all, for at least the first five years after marketing. Second, the Dutch researchers suggest that the mode of action and complexity of biologics should demand heightened safety scrutiny by regulatory authorities before approval. In addition, there is some evidence that biologics may have higher rates of safety problems than traditional drugs. This is especially worrisome since about one quarter of newly approved drugs are biologics and their numbers are expected to grow rapidly in the coming years.
One possible reform in the FDA approval process that I believe would address this concern, and which I strongly support, would be to create a new option for FDA to grant “conditional approval” of a new drug when there is any hint of serious safety problems. At present, the FDA can only approve or disapprove a new drug; there is no middle ground. A conditional approval option could constrain the use of a newly approved drug suspected of safety problems by imposing limits on its prescribing and distribution by requiring its makers to accept rigorous safety monitoring.
The pre-approval trials currently required by the FDA suffer from serious limitations. For example, there are often only a few patients in the trial and the trials are often too short to get a full picture of the drugs’ effects. As a result, safety problems often go undetected until the drug is in widespread use. By that time thousands of people may have been exposed to serious harm.
I believe that establishing a conditional approval option would be a win-win for patients. It would result in a better understanding of a new treatment’s safety and prevent harm. And it would provide access to new treatments for patients with life-threatening conditions that are unresponsive to other therapies.
Arthur A. Levin, MPH, Center for Medical Consumers ©