U.S. reviewing possible heart risks with asthma drug

WASHINGTON (Reuters) - U.S. regulators are reviewing if Roche and Novartis AG's asthma drug Xolair may be linked to an increased risk of heart attacks and strokes, health officials said on Thursday.

Preliminary findings from a study by Roche unit Genentech suggested a greater chance of heart attack, abnormal heart rhythm, heart failure, and stroke in patients treated with Xolair, the Food and Drug Administration said.

The agency said the results required further review and it was not recommending any changes to the prescribing or use of Xolair at the current time. "FDA has not made any conclusions about these data," the agency said.

Genentech spokeswoman Tara Cooper said limitations in the existing data "preclude a definitive association with Xolair use. At this time, there is insufficient information for the companies to change their assessment of the benefit-risk profile for Xolair."

The drug's 2008 sales were $517 million. Novartis and Genentech jointly market Xolair in the United States, while Novartis markets it elsewhere.

Known generically as omalizumab, Xolair is an injection that was approved in the United States in 2003. The drug works by disabling an antibody called IgE that triggers the release of chemicals that cause inflammation and provoke asthma and allergy attacks.

The study that raised concerns is ongoing and designed to evaluate Xolair's long-term safety, with a focus on cancer. Researchers are comparing patients in a real-world setting who were treated with the drug versus others who did not take it.

Cooper said the underlying health of patients differed in the two groups. Xolair-treated patients had more severe asthma and were more likely to have other health problems, she said.

The FDA said there may have been differences between the underlying risk factors for heart attacks and strokes between the two sets of patients.

The FDA notice was posted here

(Editing Bernard Orr and Carol Bishopric)