Active not recruitingPHASE1, PHASE2INTERVENTIONAL

A Study to Assess the Safety and Effectiveness of Two Experimental Malaria Vaccines

Malaria remains a major global health problem, causing hundreds of thousands of deaths each year. Researchers at the University of Oxford are developing new vaccines to combat this disease. This study is testing the safety and effectiveness of two experimental malaria vaccines, RH5.1 and RH5.2-VLP, given with a booster called Matrix-M. These vaccines aim to help your body's immune system fight off the malaria parasite. Healthy volunteers aged 18-45 will receive the vaccine, and some will be carefully exposed to malaria in a controlled setting to see if the vaccines prevent illness. The study will look at how safe the vaccines are, how your immune system reacts, and if they can stop you from getting sick with malaria.

At a glance

Status

Active not recruiting

Phase

PHASE1, PHASE2

Sponsor

University of Oxford

Enrolment target

Start

18 Aug 2023

Estimated completion

10 Mar 2026

Malaria Malaria,Falciparum Parasitic Disease Vector Borne Diseases Infections

What is this study about?

Malaria is a serious illness spread by mosquitoes that affects many people worldwide. While there have been advances, there's still a significant need for effective vaccines to protect against it and save lives. The team at the University of Oxford is working hard to develop new vaccines that can help prevent severe malaria and deaths. This research is a vital step in that process.

This study is designed to carefully check how safe these new vaccines, called RH5.1 and RH5.2-VLP, are and how well they work. A booster substance called Matrix-M is being used with the vaccines to help your body produce a stronger protective response. RH5.2-VLP is being tested in people for the very first time. Matrix-M has been given to many thousands of people before without any major safety concerns, which is reassuring.

To see if the vaccine prevents malaria, some volunteers will take part in a 'blood-stage challenge model'. This means they will be carefully given malaria parasites by injecting malaria-infected red blood cells. Please be assured this is done under very strict medical supervision, and you would be closely monitored. This controlled infection helps researchers understand how protective the vaccine is in a safe environment. All participants who receive the malaria challenge will also receive treatment to clear the infection.

Key takeaways

This study is testing new malaria vaccines to see if they are safe and effective.
Healthy adults aged 18-45 are eligible to participate.
Some participants will be exposed to malaria in a controlled setting to test vaccine protection, with immediate treatment provided.
Participation involves multiple visits over several months to over two years.
The study aims to contribute to developing a much-needed malaria vaccine.
You can withdraw from the study at any time.

Who may be eligible?

To join this study, you need to be a healthy adult between 18 and 45 years old. You should be able and willing to follow all study instructions, and we'll need to discuss your medical history with your GP. If you could become pregnant, you must use effective contraception throughout the study. We also ask that you don't donate blood during the study.

For some parts of the study, there are additional requirements. You'll need to have certain blood tests that show you don't have particular blood conditions. You must also agree not to donate blood permanently, as per UK rules for anyone participating in this type of malaria study. We need to be able to reach you easily by phone during certain periods, and you must be willing to take anti-malaria medicine after the malaria challenge, if you are in that group.

You cannot participate if you've had malaria before, taken part in other malaria vaccine studies, or if you've travelled to an area where malaria is common recently or plan to during the study. You also can't join if you've had certain medical treatments like blood transfusions or other experimental medicines recently. We'll also need to check that there's enough time between receiving this study vaccine and any other vaccinations you might have had or plan to get, such as the flu or COVID-19 jabs.

Quick self-check

Are you between 18 and 45 years old?
Are you generally healthy?
Are you able and willing to come for regular study visits in Oxford?
If you could become pregnant, are you willing to use effective contraception throughout the study?
Have you *not* had malaria before or participated in other malaria vaccine studies?
Are you willing to discuss your medical history with your GP for the study?

This is a guide only — the research team will confirm whether you can take part.

What does participation involve?

If you decide to take part, you will first have a detailed discussion about the study and complete an informed consent questionnaire to ensure you understand everything. You will receive three doses of the experimental vaccine or a placebo. After being vaccinated, some participants will be deliberately exposed to malaria infection under very controlled conditions. This involves receiving malaria-infected red blood cells.

Throughout the study, you will have regular blood tests and medical check-ups. We'll ask you to report any symptoms you experience. The study involves between 19 and 54 visits to the Centre for Clinical Vaccinology and Tropical Medicine (CCVTM) at Churchill Hospital in Oxford. The total time you'll be involved can range from 3 months to 2 years and 2 months, depending on which group you are in. It's important you can travel to the CCVTM without using public transport.

Potential risks and benefits

Taking part in a clinical trial can have potential benefits, such as contributing to scientific knowledge and the development of new treatments for serious diseases like malaria. You would also receive close medical attention and monitoring. However, there are also potential risks; the experimental vaccine might cause side effects, similar to other vaccines, such as soreness at the injection site or feeling unwell for a short while. For those undergoing the malaria challenge, there is a risk of developing malaria symptoms, although this is closely managed with prompt treatment. You are free to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (1)

Centre for Clinical Vaccinology & Tropical Medicine (CCVTM)
Oxford, United Kingdom

Common questions

What is malaria?

Malaria is a serious illness caused by parasites that are spread to people through the bites of infected female mosquitoes. It can cause fever, chills, and flu-like symptoms and can be fatal if not treated.

What is an 'experimental' vaccine?

An experimental vaccine is one that is still being tested to see if it is safe and works well. It has not yet been approved for general use, but has passed initial safety checks.

What is a 'blood-stage challenge model'?

This is a controlled medical procedure where volunteers are carefully given a small amount of malaria parasites in a safe environment. This allows researchers to see if the vaccine protects against the infection, while providing immediate treatment if needed.

Will I get malaria if I take part?

If you are in the group that receives the malaria challenge, you will be deliberately exposed to the parasite. However, this is done under very strict medical supervision, and you will receive effective anti-malaria treatment promptly to clear the infection and prevent serious illness.

What is Matrix-M?

Matrix-M is an 'adjuvant', a substance added to vaccines to help your immune system react more strongly to the vaccine, making it potentially more effective. It has been used in many people already with a good safety record.