5. Male subjects who are sexually active with female partners and are capable of fertilization must ensure that their female partners will either be postmenopausal, surgically incapable of childbearing, or will use a medically acceptable method of contraception throughout the entire study period. Medically acceptable methods of contraception that may be used by the subject and/or partner include oral contraceptives or patch, diaphragms with spermicide, IUD, condom with spermicide, or progestin implant or injection. Female partners taking oral contraceptives must have taken them consistently for at least two months prior to subject receiving study medication.