Clinical Trial: Immunogenicity and Safety of Group A, C, Y & W-135 Meningococcal Polysaccharide Diphtheria Toxoid Conjugate Vaccine

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

Official Title: A Phase 2 Double Blind Study to Evaluate Safety and Immunogenicity of Meningococcal Meningitis Serogroups A, C, Y & W-135 Polysaccharide Diphtheria Toxoid Conjugate Vaccine (NmVac4-A/C/Y/W-135-DT&

Brief Summary: The purpose of this study is to evaluate the production of antibodies to a new conjugate vaccine, NmVac4-A/C/Y/W-135-DT, as a measure of vaccine effectiveness, compared to the production of antibodies to a similar, licensed meningococcal (Groups A, C, Y, W-135) polysaccharide diphtheria toxoid (DT) conjugate vaccine. The investigators will also evaluate the safety of NmVac4-A/C/Y/W-135-DT™ conjugate vaccine compared to the licensed vaccine. The hypothesis is that the test vaccine is comparable to the licensed active control vaccine.

Detailed Summary:

Meningococcal disease is a potentially life-threatening bacterial infection. The disease most commonly is expressed as either meningococcal meningitis, an inflammation of the membranes surrounding the brain and spinal cord, or meningococcemia, the presence of bacteria in the blood. The most common symptoms include high fever, headache, neck stiffness, confusion, nausea, vomiting, lethargy, and rash. If not treated the disease can progress rapidly and can lead to shock and death, often within hours of the onset of symptoms. The disease is fatal at a rate of 10%. Of patients who recover, 10% have permanent hearing loss or other serious sequelae.

Neisseria meningitidis capsular polysaccharides are poor immunogens. However, conjugation of bacterial polysaccharides to immunogenic carrier proteins generally results in conjugates that induce strong anti-polysaccharide T-helper cell dependent immune responses, creating a longer-lasting immune response and thus protection against meningococcal infection.

The sponsor's small size Phase 1 clinical trial comprised 60 subjects. Therefore, additional data is needed to confirm the previous data with a statistically powered Phase 2 clinical trial. The present study aims to evaluate subject responses to single doses, administered in adult subjects, to determine further safety and immunogenicity of the vaccine. This study compares safety and antibody production induced by one intramuscular injection of either NmVac4-A/C/Y/W-135-DT or a licensed meningococcal (Groups A, C, Y, W-135) polysaccharide diphtheria toxoid conjugate vaccine. The primary immunogenicity endpoint will be seroresponse, based on antibody titer ≥1:8 for subjects with titer <1:8 at baseline or a 4-fold rise in antibody levels, 4 weeks after a single injection . The number and proportion of subjects achieving seror
Sponsor: JN-International Medical Corporation

Current Primary Outcome: Seroresponse (Percent Seroconversion). [ Time Frame: Week 4 after injection ]

Rise in antibody titers in serum at 4 weeks after vaccination, compared to baseline titer for meningococcal serogroups A, C, Y, and W-135. Serum Bactericidal Assay with human complement: Antibody titer ≥1:8 for subjects with titer <1:8 at baseline or a 4-fold rise in antibody levels.


Original Primary Outcome: A four fold rise in antibody titers in serum at 4 weeks after vaccination, compared to baseline titer for meningococcal serogroups A, C, Y, and W-135. [ Time Frame: Week 4 after injection ]

Serum Bactericidal Assay with human complement.


Current Secondary Outcome:

  • Solicited Adverse Events From Diary Cards [ Time Frame: Day 0 to Day 7 after vaccination ]
    Local and systemic rates from Diary Cards filled by the participants.
  • Non Solicited Adverse Events [ Time Frame: up to 6 months ]
    Non solicited local and systemic adverse Event (AE) rates throughout the course of the study, based on laboratory test results, vital signs, examination and questioning the subjects.


Original Secondary Outcome: Adverse Reactions [ Time Frame: up to 6 months ]

local and systemic rates throughout the course of the study


Information By: JN-International Medical Corporation

Dates:
Date Received: July 9, 2013
Date Started: July 2013
Date Completion:
Last Updated: April 16, 2015
Last Verified: April 2015