Pharmacological therapies have become all the rage in terms of providing new and innovative ways to prevent stroke in atrial fibrillation patients who are unable to tolerate warfarin. But as more and more clinicians begin administering these drugs and "real-world" clinical data become available, will the clinical outcomes change or more side effects crop up?
A meta-analysis published this week in Archives of Internal Medicine may stir the pot, in terms of whether physicians should administer dabigatran (Pradaxa, Boehringer Ingelheim) to patients after researchers found a small increased risk of MI or acute coronary syndrome (ACS) linked to the drug.
The researchers, therefore, recommended that clinicians use caution and consider these harmful cardiovascular events when deciding whether or not to administer the drug.
The researchers analyzed seven trials that included 30,514 patients—two trials studied stroke prophylaxis in atrial fibrillation, one acute venous thromboembolism, one ACS and three short-term prophylaxis of deep venous thrombosis. After analysis, the researchers concluded that dabigatran was linked with a higher risk of MI or ACS compared with the control group, which included warfarin, enoxaparin or placebo.
Despite this evidence, the study authors concluded that the benefit and risk balance of dabigatran appears favorable in AF patients to reduce stroke. They noted that the cardiovascular risks of the drug should be further studied, particularly when it is used in patients at a high risk of MI or ACS.
“The real clinical dilemma which surrounds the introduction of any new drug is the fact that only relatively long-term usage may provide sufficient data to reveal rare side effects, or more subtle negative balance of unwanted clinical outcomes,” an editorialist cautioned.
Previously, dabigatran has been linked to serious bleeding events. However, while FDA worked with Boehringer Ingelheim to further study these bleeding reports, FDA said that it continues to believe that the drug provides an important health benefit for patients for whom the drug is indicated.
Rivaroxaban (Xarelto, Bayer/Johnson & Johnson), another anticoagulant, has also come under fire after many questioned potential gaps in the ROCKET-AF trial design prior to the drug’s FDA approval. However, the drug has also been shown to prevent stroke in those with AF.
Due to the rather recent approvals of these types of drugs, it will take years to understand and gather long-term, “real-world” clinical data of the risks and benefits.
However, this week’s AIM study aligns with the Boston Atrial Fibrillation Symposium (BAFS) being held Jan. 12-16. This year, Drs. Christopher Granger, Jeffrey Weitz, Andrea Natale, among others, will discuss the implications and limitations of these pharmacologic therapies approved to prevent stroke in AF patients. Additionally, catheter-based approaches to prevent stroke will be discussed as alternatives to using these novel drug therapies.
Stay tuned as we report from BAFS and look for the latest conference news in Monday and Tuesday's issue of Cardiovascular Business.
Cardiovascular Business, Associate Editor