The purpose of this study is to look at the effectiveness of tenofovir disoproxil fumarate (TDF) in HIV-infected patients who have never taken anti-HIV drugs.

Patients receive TDF.

Inclusion Criteria

Patients may be eligible for this study if they:

• Are HIV-positive.
• Have a plasma viral load (level of HIV in the blood) of 10,000 copies/ml or more.
• Have a CD4 count of 50 cells/mm3 or more.
• Have a negative pregnancy test.
• Agree to use 2 forms of barrier birth control while on the study and for 30 days afterwards.
• Are 18 to 65 years old.

Exclusion Criteria

Patients will not be eligible for this study if they:

• Have had treatment with any of the following types of anti-HIV drugs: nucleoside reverse transcriptase inhibitors, nucleotide reverse transcriptase inhibitors (e.g., adefovir dipivoxil or TDF), protease inhibitors, or nonnucleoside reverse transcriptase inhibitors.
• Have received a vaccination within 30 days before study entry.
• Have had a new AIDS-defining illness diagnosed within 30 days before study entry.
• Are taking any of the following: drugs that may cause kidney problems, including aminoglycoside antibiotics, cidofovir, cisplatin, foscarnet, intravenous (IV) amphotericin B, IV vancomycin, oral and IV ganciclovir, and valganciclovir; probenecid; chemotherapy; steroid drugs; interleukin-2; or investigational drugs.
• Are pregnant or breast-feeding.
• Have difficulty taking, absorbing, or tolerating drugs by mouth, as may be shown by long-term nausea or vomiting.
• Abuse alcohol or drugs.
• Have cancer other than Kaposi's sarcoma or basal cell carcinoma.
• Have other infections that need injectable antibiotics within 15 days before study entry.
• Have had kidney or bone disease.
• Have any medical conditions or past treatments that the study investigator believes would make the patient unsuitable for the study.