People are willing to have their prothrombin time (PT) measured when they take their anticoagulants (such a Warfarin) for a short period, but after a while the constant monitoring becomes a nuisance, and there's a real risk that they'll drop the drug to avoid the monitoring! A new drug, dabigatran (Rendix®), has been tested in a clinical study and found to be a safe, effective, and more convenient alternative to enoxaparin after hip replacement surgery. The Swedish study has been reported in the medical journal Lancet. In a study funded by the manufacturer, 3500 patients were randomly allocated to take oral dabigatran (150 or 220 mg daily) or subcutaneous enoxaparin (40 mg daily) for 28 to 35 days after hip replacement surgery. Both doses of dabigatran were as effective as enoxaparin: deep vein thrombosis, pulmonary embolism, or death from any cause occurred in 8.6% and 6.0% of patients who received low-and high-dose dabigatran, respectively, compared with 6.7% of patients who received enoxaparin. The frequency of major bleeding was similar (2% or fewer) in all groups. The investigators concluded that dabigatran appears to be a safe, effective, and more convenient alternative to enoxaparin after hip replacement surgery.

Another oral direct clot inhibitor, ximelagatran, was discontinued in development because of liver toxicity. In the present study, dabigatran was not associated with an increased incidence of liver enzyme abnormalities. It looks promising for an easier-to-follow therapeutic anticoagulant option.