Is Pradaxa the Savior It Promised to Be?

Washington, DCIt's only been on the market since 2010, but Pradaxa has already come under the microscope of the US Food and Drug Administration (FDA) less than two years after the US health regulator gave the nod to dabigatran, a blood thinner. Pradaxa side effects are the concern here. And while Pradaxa is thought to carry less risk for serious bleeding than warfarin, concern remains nonetheless.

There is also some debate as to whether or not the concern is warranted.

The Los Angeles Times reported in January (1/10/12) on new research that suggests an increased risk to the heart. While the new-age blood thinner was introduced as a treatment for atrial fibrillation patients to ward off the potential for a stroke, the latest concern is that dabigatran could foster a Pradaxa Heart attack.

Given that clinical trials suggested a slight increased risk for heart attack in Pradaxa patients when compared with those who took warfarin, the FDA sought to have the data reviewed. The results, according to the LA times, revealed no statistically significant increased risk.

However, new research issued earlier this year raises additional concerns. A meta-analysis of the pooled data from seven studies found that rates of Pradaxa heart attack or chest pain (angina) were increased by 33 percent amongst patients taking dabigatran Pradaxa when compared with those patients taking another drug (such as warfarin) or a placebo.

The overall risk of a Pradaxa heart event remained small, at 1.19 percent compared with 0.79 percent. But it remains a risk, nonetheless.

The irony is that most of the data used in the meta-analysis was culled from the clinical trials that led the FDA to approve Pradaxa in the first place. Lead author in the meta-analysis was neurologist Dr. Ken Uchino of the Cleveland Clinic in Ohio. The paper was published last month in the Archives of Internal Medicine.

The lead researcher in the so-called RE-LY studies, which led to the approval of Pradaxa in 2010, noted in the LA Times article that reasons for elevated risk of heart events in Pradaxa patients over those patients taking the older warfarin, remain unclear. Dr. Stuart J. Connolly, director of the division of cardiology at Canada's McMaster University in Hamilton, suggested one possibility: that warfarin contains certain, unidentified heart benefits that dabigatran lacks.

It should be noted that Pradaxa bleeding, while always a concern when a blood thinner is used, is not as prevalent as the potential bleeding associated with warfarin. Patients in the latter camp require constant monitoring. Given that Pradaxa was the first significant alternative to warfarin to come along in 50 years, the FDA was eager to approve dabigatran provided the risk/benefit profile was appropriate.

However, the potential link to Pradaxa deaths and other adverse events has caused the FDA to further scrutinize dabigatran. And Dr. Jeremy M. Jacobs, in comments published in the LA Times, stressed the need for caution. The senior physician at Hadassah Hebrew University Medical Center in Jerusalem co-authored an editorial in the Archives of Internal Medicine that accompanied the research paper, and says that the medical community should calm their enthusiasm for Pradaxa until more research is available, "especially among patients with known active ischemic heart disease."

Pradaxa lawsuits often are the result of a bad physical or psychological experience when a switch is made from an older, more risk-prone medication to a newer product that appears to carry less risk. When that risk is found to be exacerbated after all, a Pradaxa lawsuit is sure to follow.