Safety and Immune Response to a Recombinant Adenovirus HIV-1 Vaccine in Healthy Adults

Inclusion Criteria: * Good general health * Normal hematological, hepatic and renal functions * Demonstrated understanding of study * Willing to receive HIV test results * HIV-1 and -2 uninfected * Hepatitis B surface antigen negative * Anti-hepatitis C virus (anti-HCV) negative antibody or negative HCV PCR if anti-HCV is positive * Adequate contraception. For more information on this criterion can be found in the protocol. Exclusion Criteria: * HIV vaccines or placebos in prior HIV vaccine trial * Immunosuppressive medications within 168 days prior to first injection. Participants taking corticosteroid nasal spray or topical corticosteroids are not excluded. * Blood products within 120 days prior to first injection * Immunoglobulin within 60 days prior to first injection * Investigational agents within 30 days prior to first injections * Live attenuated vaccine within 30 days prior to first injection * Any vaccine that is not a live attenuated vaccine within 14 days prior to first injection * Any clinically significant medical condition that, in the opinion of the investigator, may interfere with the study * Any medical, psychiatric, occupational, or social condition or responsibility that, in the opinion of the investigator, would interfere with the study * Serious adverse reaction to vaccines. Participants who had a nonanaphylactic adverse reaction to pertussis vaccine as a child are not excluded. * Known autoimmune disease * Known immunodeficiency * Asthma other than mild, well-controlled asthma * Diabetes mellitus type 1 or 2 * Thyroidectomy or thyroid disease in the12 months prior to study entry * Angioedema in the 3 years prior to study entry * Hypertension. More information on this criterion can be found in the protocol. * Body mass index (BMI) of 40 or higher OR BMI of 35 or greater, if other cardiovascular risk factors. More information on this criterion can be found in the protocol. * Bleeding disorder * Malignancy, unless it has been surgically removed and, in the opinion of the investigator, is not likely to recur during the study period * Seizure disorder or occurrence of seizure in the 3 years prior to study entry. Participants who have not required medications or had a seizure for prior 3 years are not excluded. * Absence of spleen * Individuals at high-risk of acquiring HIV infection * Presence of pre-existing neutralizing antibodies for Adenovirus 5 or 48 * Pregnancy or breastfeeding