Pneumococcal Vaccine Schedules Acquisition-Immunogenicity

The effect of a two-dose compared to a three-dose schedule of pneumococcal conjugate vaccine on pneumococcal acquisition, immunogenicity, and co-administration of pneumococcal conjugate and yellow fever vaccines

Status

Recruiting

Phases

Phase 4

Study type

Interventional

Source

PACTR

Registry ID

PACTR202105670402672

Enrollment

784

Registered

2021-05-06

Start date

2020-07-01

Completion date

Unknown

Last updated

2026-01-27

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

Conditions

Pneumococcal acquisition and vaccine immunogenicity

Interventions

13 valent pneumococcal conjugate vaccine

Pneumococcal conjugate vaccine

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Resident in the study area Age 0-10 weeks Intention to reside in cluster until 18 months of age

Exclusion criteria

Exclusion criteria: Intent to move out of the study area before 18 months of age Age greater than 10 weeks Prematurity <34 weeks gestation Birth weight <2.0kg or weight <2.5 kg History of invasive bacterial infection or measles Receiving long-term antibiotic therapy, i.e. greater than 4 weeks HIV infection in the infant or mother Chronic debilitating illness Immunosuppressive therapy or immunodeficiency disorder Contraindication to PCV13 – severe hypersensitivity to a previous dose of PCV13 Contraindication to YF vaccine

Design outcomes

Primary

Measure	Time frame
1. Nasopharyngeal acquisition of vaccine-type pneumococci measured using latex sweep serotyping at five timepoints between 9 and 14 months of age 2. Concentration of pneumococcal vaccine-type serotype-specific IgG measured by enzyme-linked immunosorbent assay at 18 months of age 3. Yellow fever neutralizing antibody titre expressed as the serum dilution that yields neutralisation of greater than or equal to 50% of virus infections of a standard cell line, measured 1 month after administration of yellow fever vaccine	—

Measure

Time frame

1. Nasopharyngeal acquisition of vaccine-type pneumococci measured using latex sweep serotyping at five timepoints between 9 and 14 months of age 2. Concentration of pneumococcal vaccine-type serotype-specific IgG measured by enzyme-linked immunosorbent assay at 18 months of age 3. Yellow fever neutralizing antibody titre expressed as the serum dilution that yields neutralisation of greater than or equal to 50% of virus infections of a standard cell line, measured 1 month after administration of yellow fever vaccine

—

Secondary

Measure	Time frame
1. Rate of non-vaccine type pneumococcal nasopharyngeal acquisition between 9 and 14 months of age 2. Proportion with vaccine-type pneumococcal colonisation at 6, 9 and 18 months of age 3. Proportion with geometric mean concentration of pneumococcal vaccine-type serotype-specific IgG =0.35 µg/ml, 4 weeks after the primary series and 4 weeks after the booster dose at age 9 months, and at 18 months of age 4. Pneumococcal vaccine-type opsonophagocytic antibody titres following a single dose of PCV13 at age 6 weeks, following three primary doses, following the booster dose at age 9 months, and at 18 months of age 5. Geometric mean concentrations of pneumococcal vaccine-type serotype-specific IgG 4 weeks after administration of PCV13 at 9 months of age with and without co-administration with yellow fever vaccine	—

Measure

Time frame

1. Rate of non-vaccine type pneumococcal nasopharyngeal acquisition between 9 and 14 months of age 2. Proportion with vaccine-type pneumococcal colonisation at 6, 9 and 18 months of age 3. Proportion with geometric mean concentration of pneumococcal vaccine-type serotype-specific IgG =0.35 µg/ml, 4 weeks after the primary series and 4 weeks after the booster dose at age 9 months, and at 18 months of age 4. Pneumococcal vaccine-type opsonophagocytic antibody titres following a single dose of PCV13 at age 6 weeks, following three primary doses, following the booster dose at age 9 months, and at 18 months of age 5. Geometric mean concentrations of pneumococcal vaccine-type serotype-specific IgG 4 weeks after administration of PCV13 at 9 months of age with and without co-administration with yellow fever vaccine

—

Countries

Gambia

Contacts

Public ContactJama Jack

Head of Communications MRCG at LSHTM

jjack@mrc.gm002204495442

Outcome results

None listed

Source: PACTR (via WHO ICTRP) · Data processed: Feb 4, 2026