Six weeks of anticoagulant therapy is noninferior to three months when treating young patients with acute provoked venous thromboembolism (VTE), according to a new study published in JAMA Network.
Researchers examined 417 patients younger than 21 years old who were diagnosed with acute, provoked VTE. Patients were treated in one of five different countries from 2008 to 2021. Fifty-one percent of patients were men, and the median patient age was 8 years old.
Each patient was randomized to either continue anticoagulant therapy for three months, the current standard, or six weeks.
The Kaplan-Meier estimate for the study's primary efficacy endpoint, adjudicated symptomatic recurrent venous thromboembolism, after one year was 0.66% of the six-week group and 0.70% in the three-month group.
Also, the Kaplan-Meier estimate for the study's primary safety endpoint, clinically significant bleeding episodes, was 0.65% for the six-week group and 0.70% for the three-month group.
Those differences, according to the authors, meant that the six-week option met the criteria for noninferiority.
The team also found that adverse events were seen in 26% of patients in the six-week group and 32% of patients in the three-month group. The most common event observed was fever, which was seen in 1.9% of patients in the six-week group and 3.4% of patients in the three-month group.
“Taken together, data from these recent randomized clinical trials suggest that the risks of recurrent VTE and clinically relevant bleeding events in young patients receiving anticoagulation for the treatment of acute venous thromboembolism are lower than previously reported from observational studies—particularly among patients with provoked VTE,” wrote lead author Neil A. Goldenberg, MD, PhD, a specialist at Johns Hopkins All Children’s Hospital in St Petersburg, Florida, and colleagues. "This may reflect experience gained in pediatric VTE management and an improved ability to distinguish provoked from unprovoked VTE in children and young adults."
The study did have limitations. For example, because the study population was defined by a small percentage of patients with cancer or pulmonary embolism, discretion should be used in applying the trial results to patients with those conditions.
Also, the anticoagulant therapies given to patients were mostly low-molecular-weight heparins, while direct oral anticoagulant therapies are increasingly used for the treatment of pediatric VTE.
Read the full study here.