 This group of inhibitors contain a hydroxamate (-CONHOH) group that binds the zinc atom in the active site of the MMP enzyme, therefore this group is called "hydroxamate-based MMP inhibitors“.An example can be seen in Marimastat, a first generation inhibitor, which has a similar backbone and sidechain format to collagen.Ilomastat and batimastat were the first two MMP inhibitors to be tested in patients.