Contact information
Type
Scientific
Primary contact
Dr Richard Adegbola
ORCID ID
Contact details
Medical Research Council Laboratories
Fajara
Banjul
-
Gambia
radegbola@mrc.gm
Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
WHO/RPC033
Study information
Scientific title
Acronym
Study hypothesis
Following previous encouraging findings from safety and immunogenicity studies using conjugate Pnc and Hib vaccines in the Gambia, we propose to evaluate the safety and immunogenicity of 7-valent Pnc conjugate (4, 6B, 9V 14 18C 19F 23F) manufactured by Wyeth Lederle Vaccine USA, using different vaccination schedules. The aim is to determine whether fewer doses started earlier in life with or without a booster dose of Pnc polysaccharide can induce a protective antibody response throughout infancy and early childhood. 675 young infants, residing in sites where the large efficacy (Pnc) trial is on-going, will be randomly allocated to one of 3 vaccination schedules using the 7-valent conjugate vaccine to assess the magnitude, duration and quality of the antibody- response to 1-2 doses with or without a booster dose in Upper River Division of The Gambia. The impact of this vaccination schedule on carriage of pneumococci will also be determined.
The data from this immunogenicity study and the larger on-going efficacy trial could provide important data for an informed policy decision in developing countries. We propose to use 7-valent vaccine since it is licensed and available, but would be guided by WHO as to the suitability and availability of other possible conjugate vaccines.
General objectives:
Evaluating the safety and antibody response to 1 or 2 doses of 7-valent conjugate pneumococcal (Pnc) vaccine given early in life with a booster dose of polysaccharide, compared with a standard 3-dose regimen.
Specific primary objectives:
1. To determine the immunogenicity of a 7-valent Pnc Conjugate vaccine at ages 18 weeks and 9 months, after one, two and three doses of conjugate vaccines
2. To evaluate the secondary immune response (antibody) to Pnc polysaccharide vaccine at age 10 months after one, two or three doses of 7-valent conjugate vaccine
Secondary objectives:
1. To evaluate persistence of antibody at age 15 months
2. To evaluate evidence of memory response following Conjugate vaccines using assays of antibody avidity and affinity
3. To determine naso-pharyngeal carriage of vaccine and non-vaccine serotypes at ages 6 weeks, 18 weeks, 10 and 15 months
Ethics approval
Ethics approval received from the Gambia Government/Medical Research Council (MRC) Laboratories Joint Ethics Committee on the 5th October 2004.
Study design
Randomised controlled trial
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
Not specified
Trial type
Prevention
Patient information sheet
Condition
Pneumococcus/vaccines
Intervention
Group 1: Infants here will receive their only dose of a 7-valent pneumococcal conjugate vaccine at 6 weeks of life and a dose of polysaccharide vaccine at 9 months.
Group 2: A dose of conjugate vaccine will be offered at 6 and 14 weeks, and a dose of polysaccharide at 9 months.
The third group (3) will be recruited and vaccinated at 6, 10 and 14 weeks of life with the study conjugate vaccine and with the polysaccharide vaccine at 9 months.
Intervention type
Drug
Phase
Not Specified
Drug names
Pneumococcal polysaccharide/protein conjugate vaccine
Primary outcome measures
1. Immunogenicity of 7-valent pneumococcal conjugate vaccine at ages 18 weeks and 11 months after one, two and three doses of conjugate vaccines, measuring for antibody concentrations greater than or equal to 0.35 ug/ml
2. Secondary immune response (antibody) to pnuemococcal polysaccharide vaccine at age 11 months after one, two or three doses of 7-valent conjugate vaccine (antibody concentrations greater than or equal to 0.35 ug/ml)
Secondary outcome measures
1. Persistence of antibody at age 15 months of age
2. Evidence of memory response following Conjugate vaccines using assays of antibody avidity and affinity
3. Naso-pharyngeal carriage of vaccine and non-vaccine serotypes at ages 18 weeks, 11 and 15 months of age
4. Monitoring for safety and local reaction up to 15 months of age. Two main aspects of the safety surveillance will be analysed:
4.1. Serious Adverse Events (SAE)
4.2. Local and Systemic reactions
Antibody concentrations to serotypes covered by the 7-valent conjugate vaccine (4, 6B, 9V, 14, 18C, 19F, and 23F) as well as antibody concentration to selected serotypes covered by the polysaccharide vaccine (1, 3, 5 and 12) will be measured.
Overall trial start date
01/05/2005
Overall trial end date
01/01/2007
Reason abandoned
Eligibility
Participant inclusion criteria
Babies will be recruited when they present for first dose of Diphtheria, Pertussis, Tetanus (DPT)-Haemophilus influenzae type b (Hib) vaccine and written informed consent obtained at that time
Participant type
Patient
Age group
Not Specified
Gender
Not Specified
Target number of participants
675
Participant exclusion criteria
1. Babies born to known human immunodeficiency virus (HIV) positive mothers
2. Those with neurological abnormality
3. No parental consent
4. Established pneumococcal disease
Recruitment start date
01/05/2005
Recruitment end date
01/01/2007
Locations
Countries of recruitment
Gambia
Trial participating centre
Medical Research Council Laboratories
Banjul
-
Gambia
Funders
Funder type
Research organisation
Funder name
World Health Organization (WHO)/Department of Immunisation, Vaccines and Biologicals (IVB) (Switzerland)
Alternative name(s)
Funding Body Type
Funding Body Subtype
Location
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Results - basic reporting
Publication summary