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A Multicenter, Randomized, Placebo-Controlled, Double-Blind Trial to Evaluate the Safety and Immunogenicity of a Recombinant Vaccinia-HIV-1 IIIB Env/Gag/Pol Vaccine (TBC-3B)

Phase 1
Completed
Conditions
HIV Infections
Registration Number
NCT00000767
Lead Sponsor
National Institute of Allergy and Infectious Diseases (NIAID)
Brief Summary

To evaluate, in healthy HIV-1 seronegative vaccinia-immune and vaccinia-naive volunteers, the safety and immunogenicity of an HIV-1 candidate vaccine (TBC-3B) consisting of a live recombinant vaccinia virus expressing the env, gag, and pol genes of HIV-1 IIIB strain. To evaluate the potential of boosting with one of a variety of HIV-1 recombinant subunit, peptide, or pseudovirion vaccines, if available, to augment the immune responses of the vaccinees.

Antigenic drift, defined as the genetic variation of the HIV-1 envelope gene that results in antigenic variation during natural infection, may confound attempts to achieve protective immunity using a vaccine based solely on HIV-1 envelope proteins. Inclusion of conserved core and polymerase proteins along with envelope protein in a candidate vaccine may address some of the problems with antigenic variability. A prime-boost immunization approach using a novel priming immunogen expressing env, gag, and pol genes of the HIV-1 IIIB strain will be attempted in this study.

Detailed Description

Antigenic drift, defined as the genetic variation of the HIV-1 envelope gene that results in antigenic variation during natural infection, may confound attempts to achieve protective immunity using a vaccine based solely on HIV-1 envelope proteins. Inclusion of conserved core and polymerase proteins along with envelope protein in a candidate vaccine may address some of the problems with antigenic variability. A prime-boost immunization approach using a novel priming immunogen expressing env, gag, and pol genes of the HIV-1 IIIB strain will be attempted in this study.

In Part I, vaccinia-immune volunteers are randomized to one of two regimens. Group A receives priming with TBC-3B on days 0 and 56, followed by boosting on day 224 (8 months) with one of the following: TBC-3B, an alternative immunogen such as pseudovirion particles or a recombinant HIV-1 subunit or peptide vaccine, or placebo. Group B receives priming with control vaccine (DryVax), followed by boosting with an appropriate placebo. At least 50 percent of subjects in Part I will be observed for a minimum of 8 weeks before subsequent volunteers are enrolled in Part II. PER 11/18/94 AMENDMENT, Part I boosting is given on day 392. PER 5/19/95 AMENDMENT, Part I boosting is given on day 756 if not available on day 392; if the appropriate product is not available then, the study will end on day 756. In Part II, vaccinia-naive volunteers are randomized to one of three regimens. Group C receives TBC-3B on day 0 and saline placebo on day 56. Group D receives TBC-3B on days 0 and 56. Both Group C and D receive boosting with TBC-3B or an alternative immunogen on day 224. Group E receives control vaccine (DryVax) on days 0 and 56, followed by appropriate placebo on day 224. Per 06/10/94 addendum, volunteers will be contacted once or twice per year for at least 5 years to check on health status.

NOTE: Part I (Part A) of the protocol has closed to accrual.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
18
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
Not specified
Primary Outcome Measures
NameTimeMethod
Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (5)

St. Louis Univ. School of Medicine AVEG

πŸ‡ΊπŸ‡Έ

Saint Louis, Missouri, United States

Univ. of Rochester AVEG

πŸ‡ΊπŸ‡Έ

Rochester, New York, United States

JHU AVEG

πŸ‡ΊπŸ‡Έ

Pittsburgh, Pennsylvania, United States

Vanderbilt Univ. Hosp. AVEG

πŸ‡ΊπŸ‡Έ

Nashville, Tennessee, United States

UW - Seattle AVEG

πŸ‡ΊπŸ‡Έ

Seattle, Washington, United States

St. Louis Univ. School of Medicine AVEG
πŸ‡ΊπŸ‡ΈSaint Louis, Missouri, United States

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