Response by Weitz and Eikelboom to Letter Regarding Article, “Urgent Need to Measure Effects of Direct Oral Anticoagulants”
Sueta and colleagues agree that there is an urgent need for tests to measure the anticoagulant effects of the direct oral anticoagulants,1 and they suggest that the Total-Thrombus-formation Analysis System (T-TAS) may fulfill this need. As they acknowledge, more work is needed to determine the sensitivity of this test to detect low levels of direct oral anticoagulants. Such detection is essential to identify patients who can safely undergo major surgery or receive thrombolytic therapy for acute ischemic stroke. It is important to point out that quantitative assays for direct oral anticoagulants are already commercially available, including the diluted thrombin time for dabigatran and antifactor Xa assays for rivaroxaban, apixaban, and edoxaban.1 However, these tests are not widely available. Barriers to their implementation include failure of some regulatory agencies to license the tests for clinical use and inadequate laboratory resources to introduce the tests in a rapid turnaround format in all hospitals. Therefore, before we investigate the utility of new tests, we urge regulators and hospitals to work together to implement the assays that are already available.
Jeffrey I. Weitz, MD
John W. Eikelboom, MBBS
Dr Weitz has served as a consultant and received honoraria from Bristol-Myers Squibb, Pfizer, Daiichi Sankyo, Bayer, Janssen, Boehringer Ingelheim, IONIS Pharmaceuticals, and Portola. Dr Eikelboom reports grants and honoraria from Astra Zeneca, Bayer, Boehringer Ingelheim, Bristol-Myers Squibb, Pfizer, Daiichi Sankyo, GlaxoSmithKline, Janssen, Sanofi Aventis, and Eli Lilly.
Circulation is available at http://circ.ahajournals.org.
- © 2016 American Heart Association, Inc.