Pneumococcal Conjugate Vaccine Followup

Pneumococcal Conjugate Vaccine Followup: Investigation of Serotype-specific Antibody Persistence and B Cell Memory at Age 3-5 Years Following 23valent Pneumococcal Polysaccharide Vaccine at Age 9 Months in PNG Children Previously Primed With 7valent Pneumococcal Conjugate Vaccine

Status

Completed

Phases

Phase 2

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT01414504

Acronym

PCVFU

Enrollment

280

Registered

2011-08-11

Start date

2009-12-31

Completion date

2012-09-30

Last updated

2012-09-17

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Immune Tolerance

Keywords

pneumococcal,, pneumococcal polysaccharide vaccine,, challenge dose,, hyporesponsiveness,, Papua New Guinea

Brief summary

Recently, controversy has emerged regarding the role of the 23vPPV in infants due to potential immunological hypo-responsiveness (i.e. a poorer immune response to repeat vaccination). Although previous experience of 23vPPV in children in PNG has demonstrated protective efficacy against acute lower respiratory tract infection, the investigators feel it is a matter of urgency to determine if 23vPPV administration provides elevated antibody concentrations at 3 to 5 years of age, and to ensure the immunological safety of the 23vPPV in infants. Following consent and eligibility assessment, a baseline blood sample and nose swab will be taken, a 0.1ml dose of 23vPPV will be administered and a follow up blood sample and nose swab will be collected 28 days later. The investigators will also collect data on incidence of ALRI in all study participants by medical record review.

Interventions

BIOLOGICALPrevenar + PPV

0.5mL dose of Prevenar at 0-1-2 months, 0.5mL Pneumovax at 9 months and 0.1mL Pneumovax at 3-5 yrs

BIOLOGICALInfant PCV (Prevenar) + PPV at 9 months

0.5mL Prevenar at 1-2-3 months,0.5mL Pneumovax (PPV) at 9 months, 0.1mL Pneumovax at 3-5 yrs

BIOLOGICALNo Prevenar + PPV at 9 months

no Prevenar, 0.5mL Pneumovax at 9 months, 0.1mL Pneumovax at 3-5 yrs

BIOLOGICALControl

control, 0.1mL Pneumovax at 3-5yrs

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

PREVENTION

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

3 Years to 5 Years

Healthy volunteers

Yes

Inclusion criteria

* PNG Infants aged 3 to 5 yrs of age who participated in previous PNG Neonatal PCV study and received PPV between 9 and 12 months of age, or age- and sex-matched controls who live in the same villages or urban area * Informed parental/guardian consent

Exclusion criteria

* Known HIV infection or other immunosuppressive condition or treatment. * Prior receipt of 2 doses of pneumococcal polysaccharide vaccine

Design outcomes

Primary

Measure	Time frame	Description
Measure serotype-specific antibody persistence in children aged 3-5 years after vaccination with 23vPPV at 9 months of age and compared to unvaccinated controls.	2yrs	Children who were previously vaccinated with Pneumovax (23vPPV) at 9 months will be followed up at age 3-5 years of age. They will be given a challenge dose of Pneumovax (0.1mL) and followed up 1 months later. Age matched controls identified from each villages will also be recruited and given a challenge dose of Pneumovax. Serotype-specific antibodies will be measure pre- and post-challenge dose to determine anitbody levels.

Secondary

Measure	Time frame
Measure the number of circulating serotype-specific memory B-cells pre- & post- booster immunisation	2yrs
Measure nasopharyngeal pneumococcal serotype-specific carriage rates pre- and post- 23vPPV challenge dose	2yrs

Countries

Papua New Guinea

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 24, 2026