For the first time since 1954 when warfarin emerged as the standard oral anti-coagulant prescribed to treat blood clots that form in the veins (also known as venous thrombosis), new drugs are coming onto the market. A group of researchers at the Lady Davis Institute of the Jewish General Hospital have published a meta-analysis of novel anti-coagulants tested in nine clinical trials, involving more than 16,600 patients, and concluded that two of the new entries on the market offer improvements over warfarin. Their findings appear in the prestigious British Medical Journal (BMJ).

Venous thrombosis, which affects between one and two per thousand Canadians every year, can cause deadly complications if they break free and migrate to the heart or lung. Though warfarin is an effective treatment, it does have several drawbacks. Patients on warfarin must go to the clinic once or more each month to have their condition monitored with blood tests, it has unfavourable interactions with other drugs and some food products, and it can cause dangerous bleeding. Hence, new anti-coagulants were overdue.

Rivaroxaban, which was approved this past summer by Health Canada, and dabigatran, which is expected to be approved soon, both proved to be as effective in treating venous thrombosis as warfarin. Moreover, they represent an improvement because they do not require that the patient have their blood tested, and their interactions with other drugs and food were less severe. Rivaroxaban was also associated with less risk of major bleeding than warfarin.

“From the point of view of both safety and effectiveness, I would be very confident in using these new medications to treat my patients with deep vein thrombosis,” said Dr. Susan Kahn, Director of the Jewish General Hospital Thrombosis Program and the McGill Fellowship in Thrombosis, one of the authors of the study, and a leading expert in the field.

Read the full article on the Lady Davis Institute’s website.


November 29, 2012