Participants’ HIV status is monitored monthly. Participants are also monitored for safety using periodic physical examinations, serial laboratory tests and adverse event queries. Lab tests for kidney and liver function were to be conducted at screening, months 1, 3 and every 3 months thereafter or at the final visit if early withdrawal. To minimize the risk of contracting HIV infection, participants are counseled monthly to use male condoms for each act of intercourse. Participants converting for antibodies to HIV are counseled and referred to medical services as appropriate for each country.