The manufacturers suggest that 
imatinib may inhibit the 
metabolism of 
warfarin. This suggestion seems to be based on an observation in one patient, and on 
in vitro studies that show that 
imatinib can inhibit CYP2C9, which is involved in the 
metabolism of 
warfarin. There seems to be no other evidence that a clinically relevant interaction is likely to occur.    
   The manufacturers say that patients needing anticoagulation should be given low- molecular-weight or standard heparin.