FDA Approves First Anticoagulant for Pediatric VTE

The US Food and Drug Administration (FDA) has approved dalteparin sodium (Fragmin) injection as the first anticoagulant indicated for venous thromboembolism (VTE) care in pediatric patients.

VTE—which is often a secondary complication from venous catheter, cancer, infections, congenital heart disease, trauma, and surgery—can result in deep vein thrombosis (DVT) and pulmonary embolism, either of which can result in patient death.

The heparin therapy dalteparin sodium was originally approved by the FDA 25 years ago as an anticoagulant for adults. Its efficacy in pediatric patients is based on data assessing its use in 38 children with symptomatic DVT and/or pulmonary embolism. The patients were treated for up to 3 months, with starting doses set by age and body weight. At trial’s end, 21 (55.3%) patients achieved resolution of VTE, 7 (17.9%) showed regression, 2 (5.1%) showed no change. Just 1 patient experienced recurrence of VTE, and none experienced a progression of the condition.

Common adverse effects observed in treated patients include bleeding, hemorrhage, thrombocytopenia, hematoma, injection site pain, and elevated transaminases. Currently marketed forms of dalteparin sodium carry Boxed Warnings regarding the risk of epidural or spinal hematomas in patients who are anticoagulated, due to the addition of low molecular weight heparins or heparinoids, plus neuraxial anesthesia or invasive spinal puncture.

The original marketing application for dalteparin sodium, from Pfizer, was granted Priority Review designation by the FDA. Despite the noted concerns of heparin therapy, the approval is giving a proven therapy to a patient population facing serious illness, significant complications, and even death, Richard Pazdur, MD, director of the FDA's Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA's Center for Drug Evaluation and Research, said in a statement.

"Prior to this approval, there had been no FDA-approved therapies to treat VTE in pediatric patients,” he said. “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 pediatric patients. We remain committed to advancing treatments for children with unmet medical needs."