Methods and combinations are provided for controlling the duration of action,in vivo, of matrix-degradingen-zymes. The methods and combinations permit temporary in- vivo activation ofmatrix-degrading enzymes upon administration tothe extra cellular matrix (or "ECM"). Matrix-degrading enzymes having acontrolled duration of action can be used to treatECM--mediated diseases or disorders characterized by increased deposition oraccumulation of one or more ECM components.