Related Experiment Video
Updated: Mar 29, 2026
Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/43
Published on: September 11, 2020
Reactogenicity, safety and immunogenicity of a protein-based pneumococcal vaccine in Gambian children aged 2-4 years:
A Odutola1, M O Ota1, E O Ogundare1
1a Medical Research Council Unit ; Banjul , The Gambia.
Insights
A new protein-based pneumococcal vaccine (PHiD-CV/dPly/PhtD-30) showed good safety and immune responses in Gambian children. This vaccine may overcome limitations of current pneumococcal conjugate vaccines (PCVs).
Area of Science:
- Immunology
- Vaccinology
- Pediatrics
- Infectious Diseases
Background:
- Pneumococcal conjugate vaccines (PCVs) have reduced invasive pneumococcal disease but face challenges from serotype replacement.
- Protein-based vaccines targeting common pneumococcal antigens may offer a solution to overcome PCV limitations.
Purpose of the Study:
- To assess the safety and immunogenicity of a novel protein-based pneumococcal vaccine (PHiD-CV/dPly/PhtD-30) in unvaccinated African children.
- To compare the PHiD-CV/dPly/PhtD-30 vaccine with the 13-valent pneumococcal conjugate vaccine (PCV13).
Main Methods:
- A phase II, randomized study involving 120 Gambian children aged 2-4 years, who had not previously received pneumococcal vaccination.
- Participants received a single dose of either PHiD-CV/dPly/PhtD-30 or PCV13.
- Safety was monitored via adverse events reporting; immunogenicity was assessed by measuring antibody concentrations and opsonophagocytic activity (OPA) titers pre- and 1-month post-vaccination.
Main Results:
- The PHiD-CV/dPly/PhtD-30 vaccine was well-tolerated, with adverse events occurring at a similar frequency compared to PCV13.
- Antibody concentrations against vaccine serotypes in PHiD-CV/dPly/PhtD-30 recipients were largely within the ranges observed in PCV13 recipients.
- A significant increase in antibodies against pneumolysin toxoid (dPly) and pneumococcal histidine triad protein D (PhtD) was observed one month post-vaccination in the PHiD-CV/dPly/PhtD-30 group.
Conclusions:
- A single dose of the PHiD-CV/dPly/PhtD-30 vaccine is safe and immunogenic in young Gambian children.
- This novel protein-based vaccine demonstrates potential as an alternative or adjunct to existing PCVs for preventing pneumococcal disease.
Abstract:
Pneumococcal conjugate vaccines (PCVs) have been successful in preventing invasive pneumococcal disease but effectiveness has been challenged by replacement of vaccine serotypes with non-vaccine serotypes. Vaccines targeting common pneumococcal protein(s) found in most/all pneumococci may overcome this limitation. This phase II study assessed safety and immunogenicity of a new protein-based pneumococcal vaccine containing polysaccharide conjugates of 10 pneumococcal serotypes combined with pneumolysin toxoid(dPly) and pneumococcal histidine triad protein D(PhtD) (PHiD-CV/dPly/PhtD-30) in African children. 120 Gambian children (2-4 years, not previously vaccinated against Streptococcus pneumoniae) randomized (1:1) received a single dose of PHiD-CV/dPly/PhtD-30 or PCV13. Adverse events occurring over 4 d post-vaccination were reported, and blood samples obtained pre- and 1-month post-vaccination. Serious adverse events were reported for 6 months post-vaccination. Solicited local and systemic adverse events were reported at similar frequency in each group. One child (PHiD-CV/dPly/PhtD-30 group) reported a grade 3 local reaction to vaccination. Haematological and biochemical parameters seemed similar pre- and 1-month post-vaccination in each group. High pre-vaccination Ply and PhtD antibody concentrations were observed in each group, but only increased in PHiD-CV/dPly/PhtD-30 vaccinees one month post-vaccination. One month post-vaccination, for each vaccine serotype ≥96.2% of PHiD-CV/dPly/PhtD-30 vaccinees had serotype-specific polysaccharide antibody concentrations ≥0.20µg/mL except serotypes 6B (80.8%) and 23F (65.4%), and ≥94.1% had OPA titres of ≥8 except serotypes 1 (51.9%), 5 (38.5%) and 6B (78.0%), within ranges seen in PCV13-vaccinated children. A single dose of PHiD-CV/dPly/PhtD-30 vaccine, administered to Gambian children aged 2-4 y not previously vaccinated with a pneumococcal vaccine, was well-tolerated and immunogenic.
