New warning about drug Erbitux

The U.S. government is warning doctors to monitor patients who take Erbitux, a drug for colorectal cancer, for an hour after they receive an injection because of occasional reactions that include trouble breathing, hives or dangerously low blood pressure.

The Food and Drug Administration, along with drug manufacturers ImClone and Bristol-Myers Squibb Co., on Wednesday announced changes to the drug's warning label that includes the monitoring advice. The warning says about 3 percent of patients who receive an Erbitux injection have a severe reaction. It says fatalities are rare, fewer than one-tenth of 1 percent of patients on the drug, but does not provide specifics.

In addition, the label calls for periodic monitoring of a patient taking the drug for several weeks for severe electrolyte depletion. It cites clinical trials. Erbitux is one of a new class of cancer medicines designed to specifically target and disrupt certain molecules that spur tumor growth.

Colorectal cancer is the third most common cancer and the second-leading cancer killer in the U.S. About 147,500 new cases were diagnosed last year, and it claimed 57,000 lives. The FDA has cautioned that Erbitux has not been shown to extend patients' lives. But in studies, it did shrink some patients' tumors and delay tumor growth, especially when used together with another common cancer drug.

Erbitux was the drug at the center of the ImClone Systems Inc. stock scandal that sent Martha Stewart to prison. Separately Wednesday, the FDA's advisory panel for cancer drugs recommended approval for a drug to treat anemia in people with certain kinds of blood disorders called myelodysplastic syndromes, or MDS. The drug, Revlimid, also is called lenalidomide,

MDS refers to a group of disorders caused by the bone marrow not making enough healthy, mature blood cells. About 15,000 to 20,000 new cases are diagnosed each year in the United States, and as many as 50,000 Americans have it now. They usually have anemia and fatigue and need blood transfusions about every eight weeks to stay alive.

Revlimid, made by Celegene Corp., is similar to thalidomide, a drug notorious for the birth defects it caused decades ago. In recent years thalidomide has proved effective against another blood cancer, multiple myeloma. Researchers do not really know how it works other than that it boosts the immune system in a number of ways. The FDA does not have to follow the advice of its committees but usually does, AR reports.