Clinical Trial: Safety and Immunogenicity Study of Na-GST-1 With or Without CpG

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Phase 1 Study of the Safety and Immunogenicity of Na-GST-1/Alhydrogel, With or Without a CpG ODN Adjuvant, in Healthy Adults

Brief Summary: Na-GST-1 is a protein expressed during the adult stage of the hookworm life cycle that is thought to play a role in the parasite's degradation of host hemoglobin for use as an energy source. Vaccination with recombinant GST-1 has protected dogs and hamsters from infection in challenge studies. This study will evaluate the safety and immunogenicity of two formulations of Na-GST-1 in healthy adult volunteers when co-administered with the immunostimulant CpG 10104, a Toll-like Receptor-9 agonist.

Detailed Summary: This is a Phase 1 randomized double-blind dose-escalation clinical trial in healthy hookworm-naïve adults conducted at the George Washington Medical Faculty Associates, Washington, DC, and the George Washington University School of Medicine and Health Sciences, Department of Microbiology, Immunology and Tropical Medicine, Washington, DC. In total, 24 subjects will be progressively enrolled into 2 cohorts of 12 subjects each. In the first cohort 8 subjects will receive 30µg Na-GST-1/Alhydrogel co-administered with 500µg CpG 10104 and 4 subjects will receive 100µg Na-GST-1/Alhydrogel® only, in a randomized, double-blinded fashion. In the second cohort 8 subjects will receive 100µg Na-GST-1/Alhydrogel co-administered with 500µg CpG 10104 and 4 volunteers will receive 100µg Na-GST-1/Alhydrogel only, in a randomized, double-blinded fashion. Vaccinations will be administered intramuscularly in the deltoid muscle according to a 0, 2, 4-month schedule. Each subject will participate in the study for 68 weeks (16 months) and the total duration of the study is estimated at approximately 19 months.
Sponsor: Baylor College of Medicine

Current Primary Outcome: Vaccine-related Adverse Events [ Time Frame: Up to study day 470 ]

The frequency of immediate, systemic, and local injection site adverse events, graded by severity, for Na-GST-1/Alhydrogel administered alone or in combination with CpG 10104


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • IgG antibody response to Na-GST-1 [ Time Frame: 14 days after final vaccination ]
    Dose and formulation of Na-GST-1 that generates the highest IgG antibody response at Day 126 (14 days after final vaccination), as determined by an indirect enzyme-linked immunosorbent assay (ELISA)
  • B cell response to Na-GST-1 [ Time Frame: Up to study day 290 ]
    Dose and formulation of the Na-GST-1 vaccine that results in the highest production of Na-GST-1 specific B cells and subtypes (memory or plasma)
  • Exploratory cellular immune response to Na-GST-1 [ Time Frame: Up to study day 290 ]
    Exploratory studies of the cellular immune responses to the Na-GST-1 antigen both before and after immunization.


Original Secondary Outcome: Same as current

Information By: Baylor College of Medicine

Dates:
Date Received: May 14, 2014
Date Started: October 2014
Date Completion:
Last Updated: May 30, 2017
Last Verified: May 2017