Long-term follow-up of children who participated at 9-12 months of age in clinical trial PsA-TT-007 in Mali

• Register: ISRCTN
• Last refreshed on: 9 November 2020
• Main ID: ISRCTN37623829
• Date of registration: 19/12/2016
• Prospective Registration: No
• Primary sponsor: PATH
• Public title: Long-term follow-up of children who participated at 9-12 months of age in clinical trial PsA-TT-007 in Mali
• Scientific title: A Phase IV, open-label, controlled study to evaluate the up-to-four-year antibody persistence among Malian children who previously received different doses and schedules of meningococcal conjugate group A vaccine (PsA-TT 5µg or 10µg) between 9 and 18 months of age and to assess the boosting effect following a catch-up campaign dose of MenAfriVac® (PsA-TT 10µg)
• Date of first enrolment: 06/12/2016
• Target sample size: 825
• Recruitment status: Completed
• URL: http://isrctn.com/ISRCTN37623829
• Study type: Observational
• Study design: Longitudinal observational epidemiological study (Prevention)
• Phase: Not Applicable

Countries of recruitment

Mali

Contacts

• Name: Niranjan Bhat

Key inclusion & exclusion criteria

Inclusion criteria:
Former Study PsA-TT-007 participants:
1. Received study vaccine (PsA-TT 5µg or 10µg)
2. Final evaluable blood collection must have been completed within 3 months after the second vaccination
3. Younger than 6 years of age as of March 1st, 2017
4. Written informed consent obtained from the participants’ parent(s) or guardian following international ethical guidelines for epidemiological studies and applicable local ethical guidance and requirements (added 27/02/2017)

Control participants:
1. Born between March 2011 and March 2012
2. No evidence of chronic disease
3. Younger than 6 years of age as of March 1st, 2017
4. Written informed consent obtained from the participants’ parent(s) or guardian following international ethical guidelines for epidemiological studies and applicable local ethical guidance and requirements (added 27/02/2017)

Exclusion criteria:
Exclusion criteria as of 27/02/2017:
1. Received meningococcal vaccination outside the PsA-TT-007 study (all participants, conjugate or polysaccharide)
2. Any chronic condition or medical/hereditary history suggesting participant would be immunocompromised (i.e. primary immunodeficiency, HIV, autoimmune disease)
3. Chronic administration (defined as more than 14 days) of immunosuppressant or other immune-modifying agents within the past three months (including systemic or inhaled corticosteroids, this means prednisone or equivalent, =0.5 mg/kg/day; topical steroids are allowed)
4. Administration of immunoglobulins and/or any blood products within the last 90 days.
5. Residence outside the study area for any prolonged period since birth (at the discretion of the PI) such that the potential for exposure to circulating N. meningitidis serogroup A may differ from the rest of the population (control participants only)
6. Intent to move out of the study population within the period of study conduct
7. Any condition or criteria that in the opinion of the investigator might compromise the well-being of the participant or compliance with study procedures or interfere with the outcome of the study

Original exclusion criteria:
Former Study PsA-TT-007 participants:
1. Received meningococcal vaccination outside the PsA-TT-007 study (all participants, conjugate or polysaccharide)
2. Any chronic condition or medical/hereditary history suggesting participant would be immunocompromised (i.e. primary immunodeficiency, HIV, autoimmune disease)
3. Chronic administration (defined as more than 14 days) of immunosuppressant or other immune-modifying agents within the past three months (including systemic or inhaled corticosteroids, this means prednisone or equivalent, =0.5 mg/kg/day; topical steroids are allowed)
4. Administration of immunoglobulins and/or any blood products within the last 90 days.

Control participants:
1. Residence outside the study area for any prolonged period since birth (at the discretion of the PI) such that the potential for exposure to circulating N. meningitidis serogroup A may differ from the rest of the population
2. Intent to move out of the study population within the period of study conduct
3. Any condition or criteria that in the opinion of the investigator might compromise the well-being of the participant or compliance with study procedures or interfere with the outcome of the study


Age minimum:
Age maximum:
Gender: Both

Health Condition(s) or Problem(s) studied

Meningococcal serogroup A
Infections and Infestations
Meningococcal serogroup A

Intervention(s)

Serum anti-MenA antibody levels will be measured in study participants at one or three time points, for controls as well as former PsA-TT-007 participants. The first blood draw will be performed on the day of enrollment, prior to the Mali national catch-up campaign for MenAfriVac. In a random subset of 280 participants, a second follow-up visit will be scheduled approximately 28 days after receiving a dose of MenAfriVac through the national catch-up campaign, and a third visit will be scheduled approximately 6 months after receiving the campaign dose.

Primary Outcome(s)

Geometric mean titer (GMT) for MenA-specific serum antibody as measured by serum bactericidal antibody assay using rabbit complement (rSBA) approximately four years following primary immunization.

Secondary Outcome(s)

With respect to the immune persistence time point, which will occur approximately four years following primary immunization:
1. The percentage of participants with a MenA antibody titer = 1:8, and = 1:128, as measured by rSBA assay
2. The geometric mean concentrations (GMC) for serogroup A-specific IgG concentrations, as measured by ELISA
3. The percentage of participants with serogroup A-specific IgG concentration = 2 µg/ml, and = 1 µg/ml, as measured by ELISA
Meningitis A Vaccine Sustainability Project
4. The reverse cumulative distribution curves for MenA antibody titers as measured by rSBA assay, and for MenA-specific IgG concentrations as measured by ELISA

With respect to the time points of approximately 28 days and 180 days following receipt of a single dose of MenAfriVac through a national catch-up campaign:
1. The geometric mean titer (GMT) for MenA-specific serum antibody, as measured by rSBA assay
2. The percentage of participants demonstrating a = 4-fold rise (i.e. seroconversion) in MenA antibody titers, when compared to the pre-campaign (persistence) timepoint titer, as measured by rSBA assay
3. The geometric mean concentrations (GMC) for MenA-specific IgG concentrations, as measured by ELISA
4. The ratio of GMC for MenA-specific IgG concentration in relation to the pre-campaign (persistence) time point, as measured by ELISA
5. The percentage of participants who demonstrate a = 2-fold rise and a = 4-fold rise in MenA-specific IgG concentration (i.e. seroconversion) with respect to pre-campaign (persistence) MenA-specific IgG concentration, as measure by ELISA
6. The percentage of participants with a MenA antibody titer = 1:8, and = 1:128, as measured by rSBA assay
7. The percentage of participants with MenA-specific IgG concentration = 2 µg/ml, and = 1 µg/ml, as measured by ELISA
8. The reverse cumulative distribution curves for MenA antibody titers as measured by rSBA assay and for MenA-specific lgG concentrations as measured by ELISA

Secondary ID(s)

Pers-007

Source(s) of Monetary Support

Bill and Melinda Gates Foundation

Results

• Results available: Yes
• Date Completed: 01/12/2017