A Six-week versus Three-month Duration of Anticoagulation for Acute Provoked Venous Thromboembolism in Patients < 21 Years Old: Results of the Multinational Kids-DOTT Randomized Controlled Trial

N.A. Goldenberg¹,², S. Schulman³, J.M. Kittelson⁴, T.C. Abshire⁵,⁶, M. Bonaca⁴,⁷, J.F. Casella⁸, R.A. Dale⁷, J.L. Halperin⁹, F. Hamblin², C.M. Kessler¹0,¹¹, M.J. Manco-Johnson⁴, R.F. Sidonio¹²,¹³, A.C. Spyropoulos¹⁴,¹⁵,¹⁶, P.G. Steg¹⁷, A.G.G. Turpie³, W.R. Hiatt⁴,⁷, Kids-DOTT Trial Investigators§ and the ATLAS Group

¹Johns Hopkins University, St. Petersburg, United States, ²Johns Hopkins All Children’s Hospital, St. Petersburg, United States, ³McMaster University, Hamilton, Canada, ⁴University of Colorado, Aurora, United States, ⁵Medical College of Wisconsin, Milwaukee, United States, ⁶Versiti Blood Research Institute, Milwaukee, United States, ⁷CPC Clinical Research, Aurora, United States, ⁸Johns Hopkins University, Baltimore, United States, ⁹Icahn School of Medicine at Mount Sinai, New York, United States, ¹0Georgetown University, Washington, United States, ¹¹Lombardi Cancer Center, Washington, United States, ¹²Emory University, Atlanta, United States, ¹³Children’s Healthcare of Atlanta, Atlanta, United States, ¹⁴Zucker School of Medicine at Hofstra, Manhasset, United States, ¹⁵Northwell, Manhasset, United States, ¹⁶Feinstein Institutes for Medical Research, Manhasset, United States, ¹⁷Universite de Paris, Paris, France

Abstract Number: LB 01.3

Meeting: ISTH 2021 Congress

Theme: Venous Thromboembolism » VTE Treatment

Background: In patients <21 years old with acute provoked venous thromboembolism (VTE), the optimal duration of anticoagulant therapy is unknown.

Aims: We sought to compare the net clinical benefit, as measured by the 1-year risks of symptomatic recurrent VTE and clinically-relevant bleeding, of a shortened (6-week) versus conventional (3-month) duration of anticoagulation for the treatment of first-episode acute provoked VTE in patients <21 years of age.

Methods: Following local institutional review board approval and with informed consent provided, patients <21 years old with acute provoked VTE were enrolled across 42 centers in 5 countries in an NIH-funded prospective, randomized, open-label, blinded-endpoint trial (Kids-DOTT, NCT00687882). Patients whose repeat imaging at 6 weeks post-diagnosis did not show complete veno-occlusion were randomized to discontinue anticoagulation or to continue for an additional 6 weeks. The primary efficacy and safety endpoints were symptomatic recurrent VTE and clinically-relevant bleeding within 1 year. The primary analysis was non-inferiority in the per-protocol (PP) and intention-to-treat (ITT) populations, for which 95% confidence intervals (CI) in the absolute risk differences (ARDs; 6-week minus 3-month risk) in both endpoints were evaluated.

Results: In both the PP (n=297) and ITT (n=417) populations, baseline patient and VTE characteristics (Table 1) were well-balanced between treatment arms. Kaplan-Meier estimated 1-year risks in the PP population were: primary efficacy, 0.66% (95% CI: 0.00%, 1.95%) [6 weeks] and 0.70% (95% CI: 0.00, 2.07%) [3 months]; primary safety, 0.65% (95% CI: 0.00%, 1.91%) [6 weeks] and 0.70% (95% CI: 0.00, 2.06%) [3 months]. The 6-week regimen was shown non-inferior to the 3-month regimen in both the PP and ITT populations (Figure 1).

Figure 1

Conclusions: For patients <21 years old with acute provoked VTE whose repeat imaging at 6 weeks shows no complete veno-occlusion, discontinuing anticoagulation is appropriate, with low risks of symptomatic recurrent VTE and clinically-relevant bleeding.Table 1

To cite this abstract in AMA style:

Goldenberg NA, Schulman S, Kittelson JM, Abshire TC, Bonaca M, Casella JF, Dale RA, Halperin JL, Hamblin F, Kessler0 CM, Manco-Johnson MJ, Sidonio RF, Spyropoulos AC, Steg PG, Turpie AGG, Hiatt WR, Kids-DOTT Trial Investigators§ and the ATLAS Group . A Six-week versus Three-month Duration of Anticoagulation for Acute Provoked Venous Thromboembolism in Patients < 21 Years Old: Results of the Multinational Kids-DOTT Randomized Controlled Trial [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/a-six-week-versus-three-month-duration-of-anticoagulation-for-acute-provoked-venous-thromboembolism-in-patients-21-years-old-results-of-the-multinational-kids-dott-randomized-controlled-trial/. Accessed December 7, 2021.

« Back to ISTH 2021 Congress

ISTH Congress Abstracts - https://abstracts.isth.org/abstract/a-six-week-versus-three-month-duration-of-anticoagulation-for-acute-provoked-venous-thromboembolism-in-patients-21-years-old-results-of-the-multinational-kids-dott-randomized-controlled-trial/