Emtricitabine Given Once A Day With Other Anti-HIV Drugs in Children With HIV

Inclusion Criteria Children may be eligible for this study if they: Are at least 3 months old and no older than 17 years of age. This is the age the child needs to be at the time they begin the study. Are HIV positive. Weigh more than 5.5 pounds. A newborn child must have reached at least 38 weeks of gestation. Have or have not taken anti-HIV drugs. Those that have not must have a viral load between 5,000 and 500,000 copies/ml at screening. Those that have must have been taking anti-HIV drugs, including lamivudine, for at least 3 months and have a viral load of no more than 400 copies/ml at screening. Have a CD4 count of more than 200 cells/mm3. Have written consent from parent or guardian. Are willing to use effective birth control during the study and for 1 month after the last dose of emtricitabine, if sexually active. Exclusion Criteria Children will not be eligible for this study if they: Are pregnant or breast-feeding. Cannot follow the visit or dosing schedule or are not available for 1 year. Have taken experimental drugs or vaccines (except for emivirine and experimental forms of approved drugs) within 30 days of study start. Have nerve damage in their arms or legs. Have trouble eating or taking drugs. Have serious diarrhea within 30 days before study entry. Have had any serious illness within 30 days of study screening. Any treatment must have been finished 14 days before study entry. Have had an AIDS-related (opportunistic) disease within 12 months of screening. Are being treated for tuberculosis. Have had pancreatitis. Require certain drugs.