extended safety study of tenofovir disoproxil fumarate (tdf) among hiv-1 negative men

Conditions: HIV Infection

Summary: the purpose of this study is to examine safety and tolerability of daily tenofovir use in hiv-uninfected men.

this study will assess the clinical and behavioral safety and tolerability of oral daily tdf use as pre-exposure prophylaxis (prep) to prevent hiv infection in uninfected men.

Eligibility criteria:
inclusion criteria: * healthy biologic male (male at birth) * 18-60 years of age * hiv-1 negative by licensed, commercially available, fda-approved whole blood rapid enzyme immunoassay (eia) at screening and enrollment * reports any anal sex with a man in the last 12 months * able to understand and pass comprehension assessment questionnaire * able to understand and sign a written informed consent form, which must be obtained prior to initiation of study procedures * able to understand english * adequate renal function: calculated creatinine clearance of at least 70 ml/min * hepatic transaminases (ast and alt) less than or equal to 2x upper limit of normal (uln) * total bilirubin less than or equal to 1.5 mg/dl * absolute neutrophil count at least 1,500/mm3; * platelets at least 100,000/mm3; * hemoglobin at least 9.5 g/dl * serum amylase less than or equal to 1.5 x uln * biochemical profile: within normal limits for serum phosphorus, potassium, sodium, and calcium. * hepatitis b surface antigen negative * normal urine dipstick or urinalysis (ua) exclusion criteria: * active untreated syphilis * current uncontrolled hypertension (blood pressure \> 160/100 mmhg) * mutually monogamous for \> one year with a known hiv antibody negative partner * history of chronic renal disease, known osteoporosis, osteomalacia, or osteopenia * current or expected participation in other longitudinal hiv behavioral or biomedical research study * current hiv antiretroviral use * receiving or planning to receive on-going therapy with any nephrotoxic agents or experimental/investigational agents * previous or expected requirements for the administration of immunosuppressive/ immunomodulatory therapy (e.g. chronic systemic steroids, interferon, interleukins, chemotherapy, radiation). * evidence of a gastrointestinal malabsorption syndrome or chronic nausea or vomiting which may confer an inability to receive an orally administered medication. * current alcohol or substance abuse judged by the investigator to potentially interfere with participant compliance. * imminently life-threatening medical conditions (malignancy, immunosuppressive disease \[e.g. lymphoma\]), or other serious disease or conditions (e.g. cardiovascular, renal, diabetes) within the last 5 years or that are unstable and/or require chronic medication that would impede compliance with study requirements and complicate the interpretation of adverse events * expected to be non-compliant with study visits or planning to move within 24 months to an area where the study will not be conducted * any other clinical or social condition, prior therapy, occupation, or other responsibility, that, in the opinion of the investigator, would interfere with, or serve as a contraindication to study participation or compliance with the dosing requirements.