On May 1, 2007 the U.S. Food and Drug Administration approved a new indication for dalteparin sodium injection (Fragmin, Pfizer, Inc.) to reduce the recurrence of symptomatic venous thromboembolism (VTE) in patients with cancer. VTE events included proximal deep vein thrombosis and/or pulmonary embolism. Fragmin is a low molecular weight heparin initially approved in 1994.
The safety and efficacy were evaluated in an open label clinical study of 676 cancer patients who had acute deep vein thrombosis and/or pulmonary embolism. Patients were randomized to either Fragmin 200 IU/kg daily for one month then 150 IU/kg daily for five months (Fragmin group) or Fragmin 200 IU/kg for five to seven days followed by oral anticoagulation for six months (OAC group). Fragmin was administered subcutaneously and the daily dose did not exceed 18,000 IU. The underlying cancers included breast (16%), lung (13%), gastrointestinal tract (24%), genito-urinary (22%), hematological (10%) and other cancer types (15%). Patients were followed for VTE recurrence over the entire six month period. VTE events were adjudicated by a central committee unaware of treatment assignments.
A total of 27 (8.0%) and 53 (15.7%) patients in the Fragmin and OAC groups, respectively, experienced at least one episode of recurrent VTE (p = 0.002). Most differences occurred during the first month of the study and were maintained throughout the subsequent five months. Mortality rates were similar between the study groups at the study’s conclusion. Numerically higher rates (Fragmin vs. OAC group) of major bleeding (6% vs. 4%), thrombocytopenia (11% vs. 8%) and severe (grade 3 or higher) elevations of serum ALT (4% vs. 2%) and AST (3% vs. 1%) were observed.
The recommended Fragmin dose regimen for patients with cancer and VTE consists of 200 IU/kg once daily for the first month followed by 150 IU/kg once daily for the subsequent five months. All doses are administered subcutaneously and should not exceed a daily dose of 18,000 IU. No monitoring of blood anticoagulation tests is necessary for this usage.
Full prescribing information, including clinical trial information, safety, dosing, drug-drug interactions and contraindications, is available at Drugs@FDA.
Healthcare professionals should report all serious adverse events suspected to be associated with the use of any medicine and device to FDA’s MedWatch Reporting Program via an online form, by faxing (1-800-FDA-0178) or mailing the postage-paid Form 3500 available at MedWatch , or by telephone (1-800-FDA-1088).