- Concomitant use of aspirin (> 100 mg/day), non-steroidal anti-inflammatory drugs (with the exception of COX-2 inhibitors), heparin, low molecular weight heparin or warfarin (> 1 mg/day) which was ongoing or anticipated during the study period. Low-dose aspirin (100 mg/day or less) or low-dose warfarin (1 mg/day or less) was permitted.