The US Food and Drug Administration has approved Pfizer’s Fragmin (dalteparin sodium) injection to reduce the recurrence of symptomatic venous thromboembolism (VTE) in paediatric patients one month of age and older.

The drug was initially approved by the FDA in 1994 for adults and is a type of heparin, which works as an anticoagulant. The FDA also granted this application Priority Review designation.

The efficacy of Fragmin in children was based on a single trial with 38 paediatric patients with symptomatic deep vein thrombosis and pulmonary embolism who were were treated with Fragmin for up to three months, with starting doses by age and weight.

At study completion, 21 patients achieved resolution of the qualifying VTE, seven patients showed regression, two patients showed no change, no patients experienced progression of the VTE and one patient experienced recurrence of VTE.

“Most children who have VTE are fighting a serious underlying primary illness such as cancer or congenital heart disease. Not only are they fighting a serious illness, having a condition like VTE can then lead to significant complications and even death,” said Richard Pazdur, director of the FDA’s Oncology Centre of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Centre for Drug Evaluation and Research.

“Prior to this approval,” he continued, “there had been no FDA-approved therapies to treat VTE in paediatric patients. Given the unmet need, we granted the Fragmin application priority review and today we are approving it as the first anticoagulant (blood thinner) indicated for paediatric patients. We remain committed to advancing treatments for children with unmet medical needs.”

VTE usually develops as a secondary complication of underlying clinical conditions such as a venous catheter, cancer, infection, congenital heart disease, and trauma or surgery. Paediatric VTE is associated with an increased risk of in-hospital mortality, recurrent VTE and post-thrombotic syndrome.