A Phase I/II Study of Delayed-Type Hypersensitivity (DTH) Reactions to Intradermal HIV Envelope Antigen

Previous studies in individuals immunized with gp160 suggest that a skin test response in immunized patients can be used as a surrogate marker for new proliferative and cytotoxic responses induced by vaccination.

Patients are stratified into three groups. Fifteen patients previously immunized with MicroGeneSys rgp160 antigen in ACTG 137 and not on antiretroviral therapy will receive intradermal injections of Immuno-AG rgp160 IIIB (vero cell expressed) in one arm, followed 1 week later by intradermal injections of MicroGeneSys rgp160 IIIB (baculovirus expressed) in the opposite arm (stratum 1). Forty patients who are not previously immunized with rgp160 will receive intradermal injections of Immuno-AG gp160 IIIB in one arm simultaneously with MicroGeneSys gp160 IIIB in the opposite arm; these patients are either not on antiretroviral therapy (stratum 2) or currently on antiretroviral therapy (stratum 3). All patients return 48 hours after each injection for skin test reading.

PER 4/5/95 AMENDMENT: Patients on all strata will re-enroll to receive Immuno-AG rgp160 MN in one arm simultaneously with MicroGeneSys rgp160 IIIB in the opposite arm.

Inclusion criteria

Concurrent Medication:

Allowed in Step 2 (PER 4/5/95 AMENDMENT):

• Approved antiretroviral drugs.

Patients must have:

• Documented HIV infection.
• CD4 count >= 400 cells/mm3.
• NO current active opportunistic infection or neoplasm (other than stable cutaneous Kaposi's sarcoma).

Exclusion criteria

Co-existing Condition:

Patients with the following symptoms or conditions are excluded:

• Known hypersensitivity to insect proteins.

Concurrent Medication:

Excluded:

• Antihistamine or anti-inflammatory medications for the 48-hour period between injection and skin test reading.
• Topical steroids.

Prior Medication:

PER 4/5/95 AMENDMENT -

Excluded:

• Prior immunization with experimental HIV vaccines (strata 2 and 3 only).
• Systemic corticosteroids, topical corticosteroids on the arms, or other systemic immunosuppressant agents or antineoplastic agents within 30 days prior to study entry.
• Antihistamine or anti-inflammatory medications within 72 hours prior to intradermal injections.

PREVIOUS VERSION -

Excluded within 30 days prior to study entry:

• Any antiretroviral drugs (other than AZT, ddI, ddC, or d4T for patients in stratum 3).
• Systemic corticosteroids, topical corticosteroids on the arms, or other systemic immunosuppressant agents or antineoplastic agents.

Excluded within 72 hours prior to intradermal injections:

• Antihistamine or anti-inflammatory medications.