A Multi-Center, Randomized, Double-Blind, Placebo-Controlled Study of the Efficacy and Safety of Adefovir Dipivoxil When Added to Standard Antiretroviral Therapy for the Treatment of HIV-Infected Patients With CD4 Cell Counts >= 200/mm3

Inclusion Criteria Patients must have: HIV infection with HIV RNA titer >= 2500 copies/ml (2.5 KEq/ml) plasma. CD4 count >= 200 cells/mm3. No new AIDS-defining event within the past 2 months. Life expectancy at least 1 year. Consent of parent or guardian if less than 18 years old. Tolerated antiretroviral therapy for the past 2 months. NOTE: Kaposi's sarcoma is permitted provided patient has not received systemic therapy within the past month. Exclusion Criteria Co-existing Condition: Patients with the following symptoms or conditions are excluded: Active, serious infections other than HIV that require parenteral antibiotic or antiviral therapy. Gastrointestinal malabsorption syndrome or chronic nausea or vomiting that would preclude oral medication. Malignancy other than Kaposi's sarcoma or basal cell carcinoma. Concurrent Medication: Excluded: Immunomodulating agents such as systemic corticosteroids, IL-2, or interferons. Isoniazid. Rifampin. Investigational agents (unless approved by sponsor). Systemic chemotherapeutic agents. Prior Medication: Excluded: Parenteral antibiotic or antiviral therapy for another active, serious infection within the past 2 weeks. Immunomodulating agents such as systemic corticosteroids, IL-2, or interferons within the past month. Systemic therapy for KS within the past month. Required: Antiretroviral regimen other than study drug. Required: Antiretroviral therapy for at least the past 2 months. Current alcohol or substance abuse that would interfere with compliance.