MedPath

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

Read More
Exclusion Criteria

Not provided

Read More

Study & Design

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

Trial Locations

Locations (5)

JHU AVEG

🇺🇸

Pittsburgh, Pennsylvania, United States

Vanderbilt Univ. Hosp. AVEG

🇺🇸

Nashville, Tennessee, United States

Univ. of Rochester AVEG

🇺🇸

Rochester, New York, United States

St. Louis Univ. School of Medicine AVEG

🇺🇸

Saint Louis, Missouri, United States

UW - Seattle AVEG

🇺🇸

Seattle, Washington, United States

© Copyright 2025. All Rights Reserved by MedPath