 - Males and females are eligible to enter the study. A female is eligible to enter and participate in this study if she is non-pregnant, non-lactating and if she is of: Non-childbearing potential i.e., premenstrual; or Child-bearing potential, has a negative pregnancy test at screening, and agrees to comply with one of the following during the treatment stage of the study and for a period of 90 days after stopping study medication: Complete abstinence from intercourse for 2 weeks prior to administration of study medication, throughout the study and for a period of 90 days after stopping study medication; Use of combined oral contraceptive consisting of spermicide with either condom or diaphragm; Use of intrauterine device with a documented failure rate of 1 per year; Use of depo provera injection; Male partner who is sterile prior to the female subjects entry into the study and is the sole sexual partner for that female. 