Methods for enhancing the lysis of coagulated blood comprise administering to coagulated blood a combination of clot clysis agent and a lysis enhancing amount of apolipoprotein E2 (Apo E2) or a therapeutic derivative thereof. Methods for reducing the risk of blood coagulation comprise administering to blood a combination of a clot lysis agent and a lysis enhancing amount of Apo E2 or a therapeutic derivative thereof. Additional methods for enhancing the lysis of coagulated blood comprise administering to an individual a specific level of clot lysis agent wherein the specific level is based upon the apolipoprotein phenotype of the individual. Further methods for reducing the risks of blood coagulation comprise administering to blood a specific level of a clot lysis agent wherein the specific level is based upon the apolipoprotein phenotype of the individual.