RecruitingPhase IIInterventional

A study to evaluate the tolerability and the effects on the immune system of a tetanus and diphtheria vaccine which does not need any cold chain distribution or storage

Most vaccines must be kept cold to stay effective. This can make them hard to store and deliver to remote areas or countries with limited electricity. This UK study is testing a new version of the tetanus and diphtheria booster vaccine, called SPVX02, which can be stored at room temperature. Researchers are comparing this fridge-free vaccine to an approved booster jab called Tetadif®. Around 160 healthy adults aged 18 to 60 will take part. Half will receive the new vaccine and half will receive the standard one. Participants will receive a single injection and track any side effects at home for a week using an electronic diary. Blood tests will check their immune response over 28 days. If successful, this technology could make life-saving vaccines far easier to distribute around the world.

At a glance

Status

Recruiting

Phase

Phase II

Sponsor

Stablepharma Ltd

Enrolment target

160

Start

25 Aug 2026

Estimated completion

12 Jan 2027

Tetanus and diphtheria preventative vaccination

What is this study about?

Tetanus and diphtheria are serious bacterial infections that are prevented using routine vaccinations. Tetanus enters through cuts or wounds, while diphtheria spreads through coughs and sneezes. Booster jabs are needed every so often to keep our protection topped up. However, almost all standard vaccines must be kept refrigerated from the moment they are made until they are injected. If they get too warm, they can spoil and become useless.

This trial is testing a new, freeze-dried booster vaccine called SPVX02. It has been redesigned so that it does not need a fridge or a cold supply chain. Researchers want to confirm that this room-temperature vaccine works just as well as the standard vaccine (Tetadif®) and is just as gentle on the body.

During the study, doctors will look at blood samples to count the antibodies (protective proteins) produced by participants. They will also record any side effects, such as arm soreness or mild fever, to make sure the vaccine is safe and well tolerated.

If this trial is successful, it could mark a major step forward for global public health. Fridge-free vaccines could be transported easily to disaster areas, war zones, and hot countries without reliable power, helping protect millions more people from preventable diseases.

Key takeaways

Tests a new room-temperature booster jab for tetanus and diphtheria.
Aims to remove the need for cold storage, making jabs easier to ship worldwide.
Open to healthy adults aged 18 to 60 who have not had a booster in the last 10 years.
Involves one injection, a 7-day home symptom diary, and two main clinic visits over 28 days.
Compares the new vaccine directly with an existing, approved booster.

Who may be eligible?

This trial is open to healthy adults aged between 18 and 60 who have a body mass index (BMI) of 34.9 or lower. To take part, you must have received your routine childhood vaccinations for tetanus and diphtheria, but you should not have had a booster jab in the last 10 years.

Because the study needs to measure a normal immune response, your immune system must be healthy. You cannot join if you have a medical condition or take medication that weakens your immune defences. The clinic doctor will review your general health to ensure it is safe for you to take part.

Women who are able to have children must use an effective method of birth control (such as the pill, an implant, an IUD, or condoms) throughout the study, or practice sexual abstinence. Pregnant or breastfeeding women cannot take part.

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.

I am between 18 and 60 years old.
My body mass index (BMI) is 34.9 or lower.
I had my childhood tetanus and diphtheria jabs.
I have not had a booster jab for tetanus or diphtheria in the last 10 years.
I do not have a condition that weakens my immune system.
If applicable, I am willing to use reliable contraception during the trial.

Answer every question to see your result.

What does participation involve?

Taking part lasts around four to six weeks in total. First, you will attend a screening appointment to check your medical history, confirm your past jabs, and make sure the study is right for you.

On Day 1, you will visit the clinic to receive a single injection in your upper arm. You will be given either the new fridge-free vaccine or the standard vaccine; a computer chooses which one you get, and you will not be told which one it is. After the jab, you will stay at the clinic for at least 30 minutes so nurses can check that you are feeling fine.

You will go home with an electronic diary, a thermometer, and a tape measure. For the next 7 days, you will check your temperature and measure any redness or swelling on your arm, entering the details into the diary. A study nurse may call you on Day 2 to see how you are doing. Finally, you will return to the clinic on Day 28 for a follow-up check and a blood test to measure your body's immune response before completing the trial.

Potential risks and benefits

You may receive updated protection against tetanus and diphtheria, but personal benefit cannot be guaranteed. The main benefit is helping scientists test a vaccine that could improve healthcare worldwide. The risks are similar to those of routine booster jabs. Common side effects include pain, redness, or swelling where the needle went in, as well as feeling tired, getting a mild fever, or having a headache for a few days. Serious allergic reactions are very rare, and medical staff are on hand to support you. Taking part is completely voluntary, and you are free to leave the study at any time without giving a reason and without it affecting your standard medical care.

Locations (1)

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

Medicines Evaluation Unit Limited
City only
Manchester, England

Common questions

Will I know which vaccine I am given?

No. This is a 'single-blind' trial, which means a computer randomly decides which jab you receive, but you will not be told. This helps keep the results fair and unbiased.

Do I have to pay to take part in the study?

No, taking part is free. The study sponsor provides the vaccines and all trial-related health checks.

What is the 'cold chain'?

The cold chain is the continuous system of refrigerators and cold storage boxes used to keep vaccines at safe temperatures from the factory until they are given to patients.

What should I do if I feel unwell at home?

You will record any symptoms in your electronic diary. You will also have 24-hour contact details for the trial medical team so you can call them anytime if you are worried.

Can I leave the study if I change my mind?

Yes. You can leave the trial at any point, for any reason. Your decision will not change how your GP or the NHS cares for you.

How to find out more

Karen O'Hanlon

kohanlon@stablepharma.com +44 07812606184 Official trial record

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