RecruitingInterventional

A staged dose-finding and challenge/rechallenge study of Staphylococcus aureus nasal colonisation in healthy adults

This study is investigating a common germ, Staphylococcus aureus, which often lives harmlessly in people's noses. Researchers want to understand why some people carry it without getting sick, while others don't. The study will carefully introduce a small amount of this germ into the noses of healthy adult volunteers. They will then closely monitor participants to see how the germ settles and if a first exposure can help protect against future colonisation. The findings from this research could be really important for developing new ways to prevent or treat infections caused by Staphylococcus aureus in the future. Participants will receive medication to clear the bacteria before and after the challenge, and will be monitored closely by the study team.

At a glance

Status

Recruiting

Sponsor

University of Oxford

Enrolment target

384

Start

01 Jan 2026

Estimated completion

31 Dec 2028

Staphylococcus aureus nasal colonisation

What is this study about?

Many of us carry a common type of germ called Staphylococcus aureus (often shortened to 'Staph') in our noses without ever feeling unwell. For some people, however, this germ can cause infections. Scientists don't fully understand why it lives harmlessly in some individuals but not others, or why it can sometimes cause illness.

This study aims to learn more about how this germ settles in the nose, which is also known as 'colonisation'. Researchers want to see if being exposed to the germ once can actually help protect someone from carrying it again in the future. To do this, they will carefully place a small, measured amount of Staphylococcus aureus into the noses of healthy adult volunteers. They will then watch these volunteers very closely to see what happens.

The information gathered from this study is really important. It will help scientists understand more about how these germs interact with our bodies. This knowledge could eventually lead to new and better ways to prevent or treat serious infections caused by Staphylococcus aureus in the future, improving health for many people.

Key takeaways

Researchers will place a small amount of a common germ into noses.
The study aims to understand how bacteria settle and prevent future infections.
Participants are healthy adults aged 18-55.
It involves initial health checks, special washes, and close monitoring.
Potential benefits include helping future treatments; risks include mild skin infections.
The study is taking place in Oxford and runs until December 2029.

Who may be eligible?

This study is looking for healthy adults aged between 18 and 55 years old.

To join, you need to be in good general health, and the study team will check this at an initial screening visit. You should be able to speak and understand English well enough to understand the study details and give your permission.

You also need to be able to attend all the study appointments, follow hygiene advice, and avoid certain medications like non-study antibiotics or nasal sprays during the study period. The team will want to check your medical history to make sure taking part is safe for you.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you between 18 and 55 years old?
Are you generally healthy with no serious medical conditions?
Can you attend regular appointments in Oxford and follow hygiene instructions?
Can you avoid taking non-study antibiotics or certain nasal products during the study?
Are you able to speak and understand English fluently?

Answer every question to see your result.

What does participation involve?

If you decide to take part, you'll first have a screening visit to check your overall health. If you're suitable, you'll then use a special nasal ointment and body wash for 5 days to clear any existing bacteria.

About two weeks later, you'll come back to have a very small amount of the Staphylococcus aureus germ gently dripped into your nose. For the next 28 days, you'll keep a daily record of any symptoms and attend some in-person visits for safety checks, blood tests, and swabs from your nose and body. You'll also take some nose samples at home using a kit they provide.

After this monitoring period, you'll repeat the nasal ointment and body wash treatment. Some participants might be asked to take part in a second challenge later on, depending on whether they carried the germ after the first time. The study will run from April 2026 to December 2029.

Potential risks and benefits

By taking part, you'll be contributing to vital research that could help scientists understand and fight Staphylococcus aureus infections in the future. However, there are some risks. You might get mild skin infections like small spots or pimples, although serious infections are very unlikely in healthy adults. There's a small chance you could pass the bacteria to others, so you'll need to avoid close contact with vulnerable people for a while. Blood tests can cause slight pain or bruising, and nasal swabs might be a bit uncomfortable. The special washes could cause mild irritation or, rarely, an allergic reaction. You have the right to withdraw from the study at any time, for any reason, without it affecting your medical care.

Locations (4)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

Oxford Vaccine Group
Unverified
Oxford, England
Liverpool Vaccine Group
Unverified
Liverpool, England
Sheffield Teaching Hospitals NHS Foundation Trust
Unverified
Sheffield, England
Oxford University Hospitals NHS Foundation Trust
Unverified
Oxford, England

Common questions

What is Staphylococcus aureus?

It's a common germ often found in people's noses without causing harm, but sometimes it can lead to infections.

Will I get sick if I participate?

The study is for healthy adults, and serious infections are uncommon. You might get mild skin spots, and you'll be monitored closely.

Do I have to take part in a second challenge?

No, some participants may be invited, but it's not compulsory, and it depends on whether you carried the germ the first time.

Who is paying for this research?

The Ellison Institute of Technology (UK) is providing the funding for this study.

Where is the study happening?

It's taking place in Oxford, UK, at the Centre for Clinical Vaccinology and Tropical Medicine at Churchill Hospital.

How to find out more

Conor Whelan

conor.whelan@paediatrics.ox.ac.uk +44 1865611400 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.