A Phase I Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial to Evaluate the Safety and Immunogenicity of HIV-1 Recombinant Envelope Glycoprotein gp160

Inclusion Criteria

Subjects must have:

• Normal history and physical exam.
• Negative for HIV infection by ELISA and Western blot (i.e., no reactivity at gp160, gp120, gp41, or p24).
• T4 count >= 800 cells/mm3.
• Normal chest x-ray and urinalysis.
• Negative surface antibody and core antibody for hepatitis B.
• Negative hepatitis B surface antigen.
• Negative HIV p24 antigen test.
• Normal skin reactivity by Merieux test.

Exclusion Criteria

Co-existing Condition:

Subjects with the following symptoms or conditions are excluded:

• Positive PPD.
• Syphilis, gonorrhea, or any other sexually transmitted diseases (including chlamydia or pelvic inflammatory disease).

Subjects with the following prior conditions are excluded:

• History of immunodeficiency, chronic illness, or use of immunosuppressive medications.
• Prior hepatitis B vaccination.
• Syphilis, gonorrhea, or any other sexually transmitted diseases (including chlamydia or pelvic inflammatory disease) in the past 6 months.

Prior Medication:

Excluded:

• Prior hepatitis B vaccine.

Prior Treatment:

Excluded:

• Prior blood transfusions or cryoprecipitates within the past 6 months.

Identifiable high-risk behavior for HIV infection (as determined by prescreening questions designed to identify risk factors for HIV infection), including:

• Any history of IV drug use.
• Syphilis, gonorrhea, or any other sexually transmitted diseases (including chlamydia or pelvic inflammatory disease) in the past 6 months.
• More than two sexual partners, or sexual contact with a high-risk partner, in the past 6 months.

History of severe allergic reactions to study medication Currently pregnant or breastfeeding Recent participation in another clinical trial within the last 30 days Presence of uncontrolled medical conditions that could affect safety