Aug. 13, 2009 (United Press International) -- Canadian officials say they are conducting a safety review of a potential link between the asthma drug Xolair and increased risk of cardiovascular problems.

Health Canada said the review follows the interim findings of an ongoing U.S. study that suggests an increase in such problems by patients treated with Xolair (omalizumab), including heart attacks, abnormal heart rhythms, heart failure, fainting, mini-strokes and blood clots.

In Canada, Xolair is indicated for the treatment of asthma in people 12 years old and older who have moderate to severe persistent asthma, who react to airborne allergens and whose symptoms are not adequately controlled with inhaled corticosteroids.

Although Health Canada recommends patients should not stop taking Xolair without first speaking with their doctor, the federal agency also urges patients to contact their health care professional if they have any concerns about the medicines they are taking.

Xolair is manufactured by Novartis (NYSE:NVS) Pharmaceuticals Canada.