ALVAC-HIV vCP205 is a second-generation candidate vaccine that can be used to induce a humoral and cellular response against several antigens. vCP205 expresses proteins from two strains of HIV (MN and LAI). rgp120/HIV-1SF2 expresses proteins from a different strain of HIV. This study will help to show how the immune system responds to proteins from more than one strain of virus.

Six groups of 25 volunteers each are randomized to receive simultaneous or sequential doses of ALVAC-HIV vCP205 and SF2 rgp120 or control vaccines (ALVAC-RG rabies glycoprotein vCP65 or BIOCINE Placebo Vaccine 2). In each group, 21 volunteers receive vaccine and 4 receive control vaccines. Volunteers are stratified by lower or higher risk sexual behavior. Immunizations are given to three groups at months 0, 1, 3, 6, 9, and 12, and to the other three groups at months 0, 1, 6, 9, and 12. Volunteers are followed for 24 months.

Inclusion Criteria

Volunteers must have:

• Normal history and physical exam.
• Negative ELISA and Western blot for HIV.
• CD4 count >= 400 cells/mm3.
• Normal urine dipstick with esterase and nitrite.

NOTE:

• No more than 10 percent of volunteers in each stratum may be over age 50.

Risk Behavior:

Allowed for volunteers stratified to the higher risk stratum:

High risk behavior for HIV infection, such as

• injection drug use within the past 12 months.
• higher or intermediate risk sexual behavior.

Exclusion Criteria

Co-existing Condition:

Subjects with the following symptoms or conditions are excluded:

• Positive hepatitis B surface antigen.
• Medical or psychiatric condition (such as recent suicidal ideation or present psychosis) that precludes compliance.
• Occupational responsibilities that preclude compliance.
• Active syphilis. NOTE: Subjects with serology documented to be a false positive or due to a remote (> 6 months) treated infection are eligible.
• Active tuberculosis. NOTE: Subjects with a positive PPD and a normal chest x-ray showing no evidence of TB and not requiring isoniazid therapy are eligible.
• Allergy to egg products or neomycin.
• Occupational exposure to birds.

Subjects with the following prior conditions are excluded:

• History of immunodeficiency, chronic illness, autoimmune disease, or use of immunosuppressive medications.
• History of anaphylaxis or other serious adverse reactions to vaccines.
• Prior immunization against rabies.
• History of serious allergic reaction to any substance, requiring hospitalization or emergent medical care (e.g., Stevens-Johnson syndrome, bronchospasm, or hypotension).
• Prior psychiatric condition (such as history of suicide attempts or past psychosis) that precludes compliance.
• History of cancer unless there has been surgical excision that is considered to have achieved cure.

Prior Medication:

Excluded:

• Live attenuated vaccines within 60 days prior to study entry. NOTE: Medically indicated killed or subunit vaccines (e.g., influenza, pneumococcal) do not exclude if administered at least 2 weeks from HIV immunizations.
• Experimental agents within 30 days prior to study entry.
• Prior HIV vaccines.
• Prior rabies immunization.

Prior Treatment:

Excluded:

• Blood products or immunoglobulin within the past 6 months.

For volunteers stratified to the lower risk stratum:

High risk behavior for HIV infection, such as

• injection drug use within the past 12 months.
• higher or intermediate risk sexual behavior.