The METHRO trials

Venous thromboembolism is a common and potentially fatal complication among hospital in-patients, particularly those undergoing orthopaedic surgery. Current prophylactic strategies utilise low molecular weight heparins (LMWHs) and warfarin. However, painful subcutaneous injections for LMWHs and delays in achieving target anticoagulation for warfarin pose significant problems clinically. The Melagatran for THRombin inhibition in Orthopaedic surgery (METHRO) trial represents a landmark step in the sequential combination of subcutaneous and oral anticoagulation with melagatran and ximelagatran, respectively, for surgical venous thromboprophylaxis. These agents have proven to be as effective and safe as LMWHs. Furthermore, with no need for dosage adjustment or therapeutic drug monitoring there is emerging evidence that ximelagatran may replace warfarin as the anticoagulant of choice.