Warfarin is the commonest drug now used as a blood thinner. But being on warfarin is a hassle. You have to have regular blood tests and the doses of drug you need to change may often change. Many other common drugs interfere with warfarin.
In spite of this, warfain is an important drug. It's main use is to reduce the risk of stroke for patients with a common heart rhythm disturbance - atrial fibrillation. In order to use warfarin complicated arrangements are needed - often running separate clinics either in general practice or at the hospital. Patients want a simpler and effective alternative.
Several drug companies have been working to develop such a drug for several years. Now one of these drugs is in the advanced stages of the European and British approval process. This drug is called dabigatran. The trade name is Pradaxa.
In Great Britain dabigatran was approved for short turm use in patients undergoing hip or knee replacement in 2008. Dabigatran was the subject of a large study of over 18,000 patients publised in 2009. The study was published in a leading medical journal - The New England Journal of Medicine. In this study the new drug was compared against conventional treatment with warfarin.. Two doses of dabigatran 110 and 150 mg twice daily were compared with wafarin. The trial looked at the number of strokes and bad bleeds that happened in each of the groups. The average follow up was two years.
Both doses of dabigatran were effective. It was found that those patients on high dose dabigatran had less strokes than the patients treated with warfarin. Severe bleeding was uncommon - overall rates were similar in all the patients.
What does this mean for me?
Once the drug has a license initial availability will depend on the willingness of GPs to pay for the new drug. It is clearly not possible to switch patients taking warfarin to dabigatran immediately. Whilst the change over occurs the existing warfarin service will need to continue to be funded.
Dabigatrin is not for all patients. Some groups will need to stay on warfarin at least for the present eg Patients with artificial heart valves or who have suffered a clot passing to their lungs - a pulmonary embolus.