Last month the U.S. Food and Drug Administration (FDA) approved rivaroxaban (Xarelto), a factor Xa inhibitor, for the treatment and prevention of acute deep vein thrombosis (DVT) and pulmonary embolism...making it the first oral anti-clotting drug approved for the treatment of blood clots since warfarin (Coumadin) almost 60 years ago.
The approval was primarily based on the results of three clinical trials which showed Xarelto to be just as effective as Coumadin in the treatment of DVT and pulmonary embolism with a lower risk of bleeding events. The trials' results, along with the FDA approval, could have some major treatment implications in the future.
Right now, Coumadin is one of the only oral anti-clotting treatment options available. However, it requires close monitoring of a patient's International Normalized Ratio (INR) and poses a significant bleeding risk, two major treatment obstacles for health care professionals.
On the other hand, Xarelto does NOT require INR monitoring nor does it possess the same high bleeding risk as warfarin...potentially making it the more attractive option for health care professionals.
So what does this mean for treatment?
In the short term it means we could see more patients on Xarelto. In the long term it means we could see more and more health care professionals choosing Xarelto as first line therapy over warfarin, completely altering the treatment and prevention strategy for DVTs and pulmonary embolisms. Right now patients have to endure routine INR monitoring, dietary restrictions and the fear of bleeding events if they have to be placed on an oral anti-clotting regimen. However, that could all be a thing of the past. With Xarelto as an option health care professionals can avoid the traditional obstacles of oral anti-clotting treatment and potentially improve treatment outcomes, shifting treatment toward Xarelto and away from warfarin.
Has this kind of momentous drug therapy shift occurred in the past?
Yes, there are many instances where newer drugs successfully replaced older drugs as first line therapy. For example, tricyclic antidepressants (TCA) were used for decades to treat depression until selective reuptake inhibitors (SSRIs) were introduced. SSRIs such as sertraline (Zoloft), citalopram (Celexa), and fluoxetine (Prozac) required less monitoring and presented fewer side effects when compared to TCA and therefore became the first line choice for health care professionals treating depression. However, before we place Xarelto's impact in the same category as SSRIs' impact we must first see how it does in a larger patient population size. Although the trials included over 9,000 patients we still won't know for sure how positive Xarelto's impact will be on DVT and pulmonary embolism treatment/prevention until years after it has been introduced into the general public.
With that said, Xarelto may be a viable option for health care professionals right now...
will it still be in the future or will it cement itself as the primary oral option for anti-clotting treatment...
only time will tell...after all, warfarin has over 60 years of proven effectiveness, while treatment with Xarelto is just getting started in the U.S.