Study Protocols
Vol. 1 No. 1 (2022)
Rationale and design of a study on D-dimer use to stratify patients after a first unprovoked venous thromboembolism for their risk of recurrence: extended low-dose Apixaban given only to patients with positive D-dimer results
The Apidulcis study
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All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.
Received: 22 December 2021
Accepted: 9 February 2022
Accepted: 9 February 2022
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Optimal duration of anticoagulation in patients with a first venous thromboembolism (VTE) is still uncertain. Extended anticoagulant treatment beyond the first 3 to 6 months is recommended in patients with unprovoked VTE for their high risk of recurrence, provided the risk of bleeding during anticoagulation is not high. Recent meta-analyses indicated that only one-third of these patients have a recurrence 10 years after anticoagulation is stopped, whereas the risk of major bleeding is consistent and persistent during anticoagulation. We designed the prospective, multicenter Apidulcis study to test whether serial D-dimer measurements, using commercial assays with predefined sex-specific cutoffs (350 ng/mL and 500 ng/mL for men and women, respectively, for assays expressing results as fibrinogen equivalent units), may be useful to stratify patients for the risk of recurrence. Those presenting positive D-dimer results, considered at higher risk, will receive low dose Apixaban, 2.5 mg tablets BID for 18 months, whereas those with persistently negative D-dimer results, considered at lower risk, will remain without anticoagulant treatment. Outpatients with a first VTE (unprovoked or associated with weak risk factors), aged 18 to 74 years, who have already received anticoagulation for at least 12 months are eligible for the study.
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How to Cite
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Palareti G, Prandoni P, Legnani C, Antonucci E, Zorzi S, Tosetto A, et al. Rationale and design of a study on D-dimer use to stratify patients after a first unprovoked venous thromboembolism for their risk of recurrence: extended low-dose Apixaban given only to patients with positive D-dimer results: The Apidulcis study. Bleeding Thromb Vascul Biol [Internet]. 2022 Mar. 22 [cited 2026 Jan. 21];1(1). Available from: https://www.btvb.org/btvb/article/view/10
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