Carriage to Assess Protection of New Pneumococcal Vaccines - PCV15

Summary

Streptococcus pneumoniae (pneumococcus) is a bacterium that causes just under four million serious infections every year. It is normal for pneumococcus bacteria to live in the noses of healthy adults and children as part of the nasal microflora without causing harm. This is called "carriage". But the bacteria can still be passed on to other people. If they are at-risk, for example elderly, or very young, or have pre-existing health conditions, the pneumococcus bacteria can cause pneumonia, which can cause serious life-threatening illness.

Pneumococcus bacteria are surrounded by a sugar capsule. But the capsule does not always have the same components. As a result, the bacteria are classified into more than 100 different types. To make them effective, the vaccines that are currently available contain the sugar capsules of the most common pneumococcal types that cause disease.

One such vaccine - PCV13 - has been effective globally in protecting against pneumococcus disease. It works because it controls the "carriage" (how a person carries the bacteria in their nose) of 13 types of the bacteria. Vaccines giving protection against other types of the bacteria are also becoming available worldwide. PCV15 is similar to PCV13 and protects against two additional types of the bacteria so may offer more protection.

This study, which lasts 2 months and is funded by Merck Sharp \& Dohme (MSD), aims to assess if using PCV15 can protect against "carriage". To do this, investigators will use a well-established method already used with more than 2,000 people safely in other research. This involves "challenging" volunteers by putting a small amount of the pneumococcus bacteria into their noses. In this study, before they are challenged, volunteers will either be vaccinated with the real PCV15 vaccine or a dummy ("placebo"). The Investigators will then be able to compare the two groups to find out who the vaccine protected and who it did not.

After the study everyone who takes part and fit into certain criteria will be given antibiotics to clear the pneumococcus colonisation. They will also be regularly monitored during the study to ensure their safety.

A very small number of volunteers will be asked to have a biopsy to collect tissue samples from inside their nose before and after being vaccinated with PCV15. This will help researchers to understand more about how the immune system responds to the vaccine.

The information gain in this project will help the investigators to understand how exactly PCV15 vaccine protects people against pneumococcus. This means that this vaccine and future pneumococcal vaccines will be improved to protect many lives in future around the world.

Conditions

• Pneumococcal Disease
• Pneumococcal Carriage

Interventions

BIOLOGICAL

PCV15

VAXNEUVANCE (Merck, Sharp \& Dohme LLC, a subsidiary of Merck \& Co, Inc., Rahway, NJ, USA \[MSD\]) is a 15-valent PCV containing capsular polysaccharides from serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 23F, 22F, and 33F adjuvanted with aluminium phosphate.

BIOLOGICAL

Streptococcus pneumoniae serotype 3

Streptococcus pneumoniae SPN3 (Clade Ia, strain LIV014-S3) - Single inoculation at 80,000 colony-forming unit (CFU)/naris, 28 days after vaccination.

BIOLOGICAL

Placebo

The placebo consists of 0.9% sodium chloride for injection

Sponsors & Collaborators

• Liverpool School of Tropical Medicine, United Kingdom

  collaborator UNKNOWN

• Oxford University Hospitals NHS Trust

  collaborator OTHER

• University of Oxford

  lead OTHER

Principal Investigators

• Simon Drysdale, MRCPCH, PhD, PgDip PID, FRCPH · University of Oxford

• Daniela M Ferreira, PhD · University of Oxford

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

TRIPLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

50 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2025-02-24

Primary Completion

2025-12-31

Completion

2026-12-31

Countries

• United Kingdom

Study Locations