A Phase IV, Experimental Human Pneumococcal Challenge (EHPC) Model to Investigate Streptococcus Pneumoniae Serotype 3 (SPN3) Colonisation Following PCV15, a Double Blind Randomised Controlled Trial (DBRCT) in Healthy Participants Aged 18 - 50 Years in the UK.
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.
• Adults between 18 to 50 years old (inclusive) at the time of enrolment.
• Medically healthy, such that according to investigator judgement, hospitalisation within the study period is not anticipated, and the participant appears likely to be able to remain a study participant through to the end of protocol-specified follow-up. Planned elective procedures for pre-existing conditions may be allowable.
• Fluent spoken English - to ensure a comprehensive understanding of the research project and their proposed involvement.
• Able to attend the scheduled visits and to comply with all study procedures, including internet access for the recording of electronic diary after inoculation.
• Willing and able to give informed consent for participation in the study.
• Willing to allow confirmation of past medical history either through provision of, or access to, a medical record summary or other medical documentation or allowing investigators to obtain a copy of their medical history from their GP practice or accessed via electronic patient records.
• Willing to allow their GP and/or consultant, if appropriate, to be notified of participation in the study.
• Willing to provide their national insurance number or passport number to be registered on The Over-Volunteering Prevention System (TOPS).
• For participants of childbearing potential only: willing to use effective contraception for the duration of the study AND to have a pregnancy test on the day of screening and challenge.