Active not recruitingNAINTERVENTIONAL

BCG Revaccination Study in Diabetic and Non-Diabetic Adults

This study is exploring better ways to use the BCG vaccine for tuberculosis (TB), especially in adults. Currently, the BCG jab you get as a child doesn't always work as well for adults. We're testing if giving BCG as a breathed-in mist (like an inhaler) works better than the usual injection. We're also keen to understand if there's a difference in how people with and without Type 2 Diabetes react to this booster vaccine. Diabetes can make people more likely to get TB, so finding better ways to protect them is important. We will involve 36 people who've had BCG before and will take blood and lung samples to see how their bodies respond.

At a glance

Status

Active not recruiting

Phase

Sponsor

University of Oxford

Enrolment target

Start

03 Apr 2024

Estimated completion

31 Aug 2028

Tuberculosis

What is this study about?

Tuberculosis (often called TB) is a serious infection that sadly still causes many deaths worldwide. The main way we try to prevent it is with a vaccine called BCG (Bacille Calmette-Guérin). While the BCG jab works quite well for babies and children, it's not always as effective in adults, which is a problem.

This study is trying to find out if we can make the BCG vaccine work better, especially for adults. We're looking at two main things. Firstly, instead of giving the vaccine as an injection under the skin, we want to see if breathing it in as a fine mist (like an inhaler) could be more effective. Some exciting animal research suggests this might be a better way for the body to learn to fight TB. We've also safely tested this breathing-in method in other studies before.

Secondly, we know that people with Type 2 Diabetes are more likely to get TB and can get sicker from it. We want to understand if their immune system reacts differently to the BCG vaccine compared to people who don't have diabetes. By understanding these differences, we hope to find better ways to protect everyone, especially those at higher risk, from this serious disease. We'll be looking closely at their blood and small samples from their lungs to see how their body responds.

Key takeaways

The study explores two ways to give the BCG vaccine for TB: injection vs. breathing it in.
It aims to see if breathing the vaccine in makes it more effective, especially for adults.
Researchers want to understand how people with and without Type 2 Diabetes respond to the vaccine.
This could lead to better protection against TB globally.
You'll need to have had the BCG vaccine before to take part.
Participation involves screening, vaccination, blood tests, and a lung sample (bronchoscopy).

Who may be eligible?

This study is looking for healthy adults between 18 and 65 years old. You need to live close enough to Oxford to attend all appointments. It's really important that you've had the BCG vaccine before, and we'll need to see proof of this, like a scar or a medical record. We're interested in two groups of people: those who are healthy, and those who have had Type 2 Diabetes for at least a year and are managing it with medication like metformin.

There are also some important reasons why you might *not* be able to take part. For example, if you're pregnant or trying to get pregnant, if you have certain serious health conditions like a severe allergy history, cancer (apart from very common skin cancers or cervical changes), or if you're taking part in another research study at the same time. You also shouldn't have had a positive test for TB in the past. We'll ask about your full medical history to make sure it's safe for you.

If you're a woman who could become pregnant, you'll need to use reliable contraception throughout the study and have negative pregnancy tests at key times.

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 65 years old?
Have you had the BCG vaccine before (with proof like a scar or record)?
Are you able to travel to Oxford for appointments?
If you have Type 2 Diabetes, has it been diagnosed for at least a year and are you on medication like metformin?
Are you generally healthy and don't have certain serious health conditions or allergies?
Are you willing and able to use reliable contraception if you could become pregnant?

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 make sure you're suitable for the study. This will involve a health check, some questions about your medical history, and blood tests. Once accepted, you'll receive the BCG vaccine, either as an injection or by breathing it in as a mist. We're looking for 36 people in total.

About 14 days after getting the vaccine, you'll have a procedure called a bronchoscopy. This involves passing a thin, flexible tube with a camera down into your lungs to collect a small sample, which helps us see how your lung lining is responding to the vaccine. This procedure is done while you're awake but with medication to make you comfortable and numb your throat.

Throughout the study, we'll take several blood samples to check your body's immune response. You'll have several follow-up visits after the vaccination and bronchoscopy. The exact number of visits and the total length of the study will be explained in detail, but you should expect to commit to a series of appointments over a period of time. You'll also need to agree not to donate blood during the study.

Potential risks and benefits

By taking part, you could be helping us learn more about how to make the BCG vaccine better and how to protect people from TB, especially those with diabetes. This research may not directly benefit you, but it could help many others in the future. As with any medical procedure or trial, there are potential risks, such as side effects from the vaccine (like redness or soreness where it's given, or minor reactions if you breathe it in) and risks associated with the bronchoscopy procedure, though these are generally considered safe. You will be fully informed about these risks. Remember, you can change your mind and withdraw from the study at any time, for any reason, without it affecting your medical care.

Locations (1)

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

Centre for Clinical Vaccinology and Tropical Medicine
Verified postcode
Oxford, United Kingdom

Common questions

What is the BCG vaccine?

The BCG vaccine is a jab commonly given to protect against tuberculosis (TB), especially in children. It helps your body learn to fight the TB germ.

What is tuberculosis (TB)?

TB is a serious infection, usually affecting the lungs, caused by a type of germ. It can make you very ill if not treated.

What does 'inhaled BCG' mean?

Instead of an injection, 'inhaled BCG' means you would breathe the vaccine in as a fine mist, similar to how some asthma medications are taken.

Why are you studying people with Type 2 Diabetes?

People with Type 2 Diabetes can be more vulnerable to TB, so we want to see if the vaccine works differently for them and find better ways to protect them.

What is a bronchoscopy?

It's a procedure where a thin, flexible tube is gently passed into your lungs to take a small sample. It's done to see how the vaccine affects your lung lining.