 4. Women of childbearing potential and all men must use adequate contraceptive measures if sexually active. Examples include abstinence, oral contraceptives or other form of hormonal contraception, intrauterine devices, surgical sterilization, or barrier forms of contraception with spermicidal jelly. Subjects must agree to continue to use these contraceptive measures and agree not to become or plan a pregnancy within 12 months of the date of the last study drug administration. 