Genentech Issues Warning on Cancer Drug
Genentech Inc., the world’s No. 2 biotechnology company, on Thursday warned U.S. doctors about 15 deaths from allergic reactions linked to use of its cancer drug Herceptin, one of the company’s fastest-growing products.
Shares of Genentech, which is majority-owned by Swiss drug maker Roche Holding, fell $4.50, or nearly 4%, to close at $119 on the New York Stock Exchange.
In a letter, the company warned U.S. physicians to closely monitor patients at risk for serious reactions to the drug. It said the deaths resulted from allergic reactions when Herceptin was given in an intravenous infusion. About 62 serious reactions of this type have been reported among the nearly 25,000 patients who have been given the drug, said Genentech spokesman Neil Cohen.
The new warning could make some doctors and patients think twice before deciding to use the drug, said Charles Engelberg, an analyst with AmeriCal Securities and a physician who is trained as an oncologist.
“It’s not that material from a survival standpoint. But from a psyche standpoint, it will have its impact on the doctors and patients,” Engelberg said.
Herceptin is one of Genentech’s most important drugs because it and a second cancer drug, Rituxan, have helped keep profit and revenue growing as older products such as heart treatment Activase and growth hormones have matured.
First-quarter Herceptin sales soared 72% to $68.7 million from $39.9 million a year earlier. The drug won U.S. approval in September 1998.
The so-called dear-doctor letter warns physicians to “use extreme caution” in giving the drug to patients with advanced lung disease whose cancer hasn’t responded to several rounds of chemotherapy, Cohen said.
Although the letter raises new questions about the safety of Herceptin, the drug is still far less toxic than older, commonly used chemotherapy drugs that attack the body as well as the tumor.
South San Francisco-based Genentech and the Food and Drug Administration are in discussions over plans to include the warning in the drug’s labeling, Cohen said.
Because the problems weren’t seen during clinical trials of the drug, the FDA became aware of the risks only after reviewing reports of unexpected side effects sent by doctors, patients and the company. Though the agency said it was difficult to draw strong conclusions based on the reporting system, it is important for doctors to know about the problems.
The safety problems Genentech flagged about Herceptin are similar to problems with another cancer drug, Rituxan.
Rituxan, which was developed by Genentech and Idec Pharmaceuticals Corp., carries a “black- box warning,” the FDA’s most- stringent caution. The warning informs doctors that infusion-related deaths happen at a rate of four to seven for every 10,000 patients. That’s similar to the rate of infusion-related death in Herceptin patients.
Rituxan sales have risen since December 1998, when the problem first surfaced. First-quarter Rituxan sales rose 49% to $85.1 million from $57 million a year earlier.
