According to a new study published in JAMA, treatment with low molecular-weight heparin tinzaparin did not significantly reduce recurrent venous thromboembolism (VTE) or major bleeding and overall mortality compared to warfarin, but it did significantly reduce the risk of clinically relevant non-major bleeding in patients with active cancer.
Agnes Y. Y. Lee, MD, MSc, from the University of British Columbia, and colleagues conducted a study of 900 adult patients with active cancer and documented deep vein thrombosis or pulmonary embolism across 164 centers from August 2010 to November 2013. Patients were randomized to tinzaparin once daily for six months or the conventional therapy of tinzaparin once daily for 5–10 days then dose-adjusted warfarin to maintain therapeutic international normalized ratio (INR) for six months. Patients were followed up for 180 days and for 30 days after the last dose for safety data.
Tinzaparin did not significantly reduce recurrent VTE occurrence compared to warfarin (six-month cumulative incidence 7.2% vs 10.5%, respectively). There were no differences in major bleeding (12 patients for tinzaparin vs 11 patients for warfarin) or in overall mortality (150 patients for tinzaparin vs 138 patients for warfarin).
Tinzaparin did, however, significantly reduce clinically relevant non-major bleeding, which included bleeding that required any medical or surgical intervention but was non-fatal; bleeding that did not occur in a critical area or organ, did not cause a fall in hemoglobin >2g/dL, or required a transfusion of ≥2 units of whole blood or red cells. A total of 49 out of 449 patients treated with tinzaparin had clinically relevant non-major bleeding vs. 69 out of 451 patients treated with warfarin.
The researchers concluded this trial supports the safety of tinzaparin use in active cancer patients. They noted that further studies are necessary to assess the efficacy of tinzaparin use in patients at a higher risk of recurrent VTE.
For more information visit JAMAnetwork.com.