Protein Dose-Sparing Effect of AS01B Adjuvant in a Randomized Preventive HIV Vaccine Trial of ALVAC-HIV (vCP2438) and Adjuvanted Bivalent Subtype C gp120

J Infect Dis. 2024 Aug 16;230(2):e405-e415. doi: 10.1093/infdis/jiad434.

Abstract

Background: HVTN 120 is a phase 1/2a randomized double-blind placebo-controlled human immunodeficiency virus (HIV) vaccine trial that evaluated the safety and immunogenicity of ALVAC-HIV (vCP2438) and MF59- or AS01B-adjuvanted bivalent subtype C gp120 Env protein at 2 dose levels in healthy HIV-uninfected adults.

Methods: Participants received ALVAC-HIV (vCP2438) alone or placebo at months 0 and 1. At months 3 and 6, participants received either placebo, ALVAC-HIV (vCP2438) with 200 μg of bivalent subtype C gp120 adjuvanted with MF59 or AS01B, or ALVAC-HIV (vCP2438) with 40 μg of bivalent subtype C gp120 adjuvanted with AS01B. Primary outcomes were safety and immune responses.

Results: We enrolled 160 participants, 55% women, 18-40 years old (median age 24 years) of whom 150 received vaccine and 10 placebo. Vaccines were generally safe and well tolerated. At months 6.5 and 12, CD4+ T-cell response rates and magnitudes were higher in the AS01B-adjuvanted groups than in the MF59-adjuvanted group. At month 12, HIV-specific Env-gp120 binding antibody response magnitudes in the 40 μg gp120/AS01B group were higher than in either of the 200 μg gp120 groups.

Conclusions: The 40 μg dose gp120/AS01B regimen elicited the highest CD4+ T-cell and binding antibody responses. Clinical Trials Registration . NCT03122223.

Keywords: HIV; adjuvant; dose; vaccine.

Publication types

  • Randomized Controlled Trial
  • Clinical Trial, Phase II
  • Clinical Trial, Phase I

MeSH terms

  • AIDS Vaccines* / administration & dosage
  • AIDS Vaccines* / adverse effects
  • AIDS Vaccines* / immunology
  • Adjuvants, Immunologic* / administration & dosage
  • Adolescent
  • Adult
  • Double-Blind Method
  • Female
  • HIV Antibodies* / blood
  • HIV Antibodies* / immunology
  • HIV Envelope Protein gp120* / immunology
  • HIV Infections* / immunology
  • HIV Infections* / prevention & control
  • HIV-1 / immunology
  • Humans
  • Male
  • Polysorbates / administration & dosage
  • Squalene / administration & dosage
  • Viral Vaccines
  • Young Adult

Substances

  • Adjuvants, Immunologic
  • AIDS Vaccines
  • HIV Envelope Protein gp120
  • HIV Antibodies
  • Squalene
  • MF59 oil emulsion
  • Polysorbates
  • ALVAC vaccine
  • Viral Vaccines

Associated data

  • ClinicalTrials.gov/NCT03122223