Recombinant agents affecting thrombosis

A pharmaceutical composition for the inhibition or treatment in a human or animal subject of a condition selected from the group consisting of inflammation, restenosis, and complications of transplantation, which composition comprises an amount of a Factor Xai peptide modified from the native amino acid sequence of light chain positions 1-139 and heavy chain positions 1-245 of FIG. 1, wherein said Factor Xai is capable of competing with Factor Xa in the formation of prothrombinase complex and wherein said Factor Xai does not result in proteolytic activity when included in said complex, wherein the serine residue at position 185 of the heavy chain shown in FIG. 1 is replaced by an alternate amino acid and/or the aspartic acid residue at the position 88 of the heavy chain shown in FIG. 1 is replaced by an alternate amino acid and/or the histidine residue at position 42 of the heavy chain shown in FIG. 1 is replaced by an alternate amino acid, said peptide being present in an amount effective to ameliorate or prevent the condition in admixture with a pharmaceutically acceptable carrier.