9. For female subjects: Serum or urine Positive pregnancy test, presently breast-feeding, or unwillingness to use effective contraceptive measures for the duration of the study and 4 months after discontinuation. For male subjects: intent to procreate during the duration of the study or within 4 months after discontinuation or unwillingness to use effective measures of contraception. If sexually active, subject must use at least two medically accepted methods of birth control from the following list: oral contraceptives, Norplant®, Depo-Provera®, intrauterine device (IUD), barrier devices with spermicide. Condoms used alone are not acceptable. Instead of the male condom, it is acceptable to use a female condom with one of the other methods for women listed above.