AF Symposium 2015

Daniel W. Singer, MD
The Novel Oral Anticoagulants: Xarelto Best Seller
by Steve S. Ryan, PhD, Updated August 2015
Dr. Daniel Singer of Mass General updated our info about the NOACs (Novel Oral Anticoagulants). Rivoraxaban (Xarelto) is now the most commonly prescribed NOAC. (This is somewhat surprising since dabigatran [Pradaxa] was the first NOAC approved by the FDA and for many months was the only alternative to warfarin. But Pradaxa has lost market share, possibly because of the bad publicity about deaths in the ER from not being able to stop bleeding and its law suit settlements.) (See also: Stop Prescribing or Taking Pradaxa: Suspect in 542 Patient Deaths and Warfarin vs. Pradaxa and the Other New Anticoagulants )
NOACs More Prescribed for New Patients Than Warfarin
After a slow start, NOACs are now prescribed by doctors more commonly than warfarin for new A-Fib patients.
How Do We Know Patients are Actually Taking NOACs and Getting Adequate Levels of Anticoagulation?
The obvious problems with NOACs are they are very costly compared to warfarin, and there currently aren’t any reversal agents like there are for warfarin. But Dr. Singer raised another problem. How can we know the patient is taking the NOAC, what anticoagulant level are they reaching? With warfarin we have INR levels and years of experience in monitoring. Dr. Singer thinks that with more time and clinical experience, we may get a better handle on how the NOACs are actually performing.
GI Bleeding Preferable to Brain Bleeds
Some NOACs produce gastrointestinal bleeding and damage. But Dr. Singer pointed out that from his perspective that is acceptable. No one wants to have gastrointestinal bleeding. But compared to intracranial bleeds, GI bleeds are seldom lethal and don’t leave people disabled.
Editor’s Comments:
Dr. Singer didn’t venture to distinguish between the various NOACs because there haven’t been any head-to-head trials. But, in this editor’s opinion, Eliquis tested better and is safer than the others.
NOTE: Another NOAC Edoxaban (Lixiana) was approved by the FDA in January, 2015.
Update August 15, 2015:
See also: Edoxaban Compared to Other Blood Thinners.
An experimental drug idarucizumad has show positive results as a reversal agent for Pradaxa (dabigatran). In a new study of 90 patients who had uncontrolled bleeding with Pradaxa, idarucizumad stopped this bleeding within minutes. No serious side effects were reported. FDA approval is pending.
We have previously reported on the reversal agent Andexanet Alfa which is on FDA fast track approval as an antidote to the Factor Xa inhibitors Xarelto and Eliquis. FDA approval is pending.