(October 21, 2008 - Insidermedicine) There is evidence that many biological drugs pose safety risks that do not become apparent until years after the drug is approved, according to research published in the Journal of the American Medical Association.

Here are some facts about biological drugs:

•    They are drugs in which the active ingredient is produced from a biological source, such as antibodies, enzymes, and hormones.

•    Biological drugs have revolutionized the treatment of many hard-to-treat conditions, including some cancers and autoimmune diseases like rheumatoid arthritis.

•    Biological drugs are more effective than many conventional drugs, but they also have the potential to be more toxic.

Researchers out of Utrecht University analyzed safety-related measures issued by drug regulatory agencies in the United States and/or the European Union for biological therapies approved between January 1995 and June 2007.

Nearly one-quarter of the 174 drugs the investigators assessed had been issued a safety-related action. Most of these were in the form of letters to health care professionals warning them about previously unrecognized side effects, but 19 ‘black box warnings’ about potentially serious health hazards were also issued. None of the drugs were removed from the market for safety reasons. Most of the safety-related regulatory actions were issued within five years of the drug being approved.

Today’s research highlights the flaws in the current system of new drug approvals and surveillance. While biological therapies can be very effective, it is important to be aware of the potential for unexpected side effects. Never change the way you take your prescription medication without first talking to your health care professional.

For Insidermedicine in Depth, I'm Dr. Susan Sharma.