An open label, non-comparative, pharmacokinetic and pharmacodynamic study to evaluate the effect of Dabigatran Etexilate on coagulation parameters including a calibrated thrombin time test in patients with moderate renal impairment (creatinine clearance 30-50 ml/min) undergoing primary unilateral elective total knee or hip replacement surgery

There is limited clinical expierience with dabigatran etexilate administration
to patients with moderate renal impairment. Some patients, e.g. elderly
subjects with moderate to severe renal impairment, might be at increased risk
of bleeds due to prolonged elimination of dabigatran. A follow-up measure was
agreed with the EMEA to evaluate a calibrated commercial coagulation assay for
the measurement of blood coagulation time in patients with moderate renal
impairment.

To asses the comparability of the estimated dabigatran concentration in plasma
via calibrated Hemoclot and the measured dabigatran concentrations assessed in
a central lab in patients with moderate renal impairment undergoing primary
unilateral elective total knee or hip replacement surgery.

Multi-centre, open label, non-comparative uncontrolled study. All patients will
be receiving dabigatran etexilate (Pradaxa) 150 mg taken once daily as 2
capsules of 75 mg; duration of treatment - 10 days. At day of surgery the
treatment will be initiated 1-4 hours post surgery with half a dose (75 mg).

All patients will receive 150 mg dabigatran etexilate (Pradaxa) taken once
daily as 2 capsules of 75 mg, at the day of surgery the treatment will be
initiated 1-4 hours post surgery with half a dose.

The standard profylaxis will be replaced by Pradaxa. Next to the planned
surgery a physical examination will be performed and during the study 12 -13
venapunctures will be taken to obtain blood samples. Woman of child-bearing
potential will undergo a urine prengnancy test.