Clinical Research Directory

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

Malaria is a major public health problem. There were around 240 million cases of malaria and 627,000 deaths worldwide in 2020. There is a great need for a safe, effective malaria vaccine and the team at University of Oxford is trying to make vaccine(s) which can prevent serious illness and death. This study is being done to assess an experimental malaria vaccine for its ability to prevent malaria illness. This is done using a 'blood-stage challenge model'. This is when volunteers are infected with malaria parasites using malaria-infected red blood cells. The vaccine we are testing in this part of the study is called "RH5.2-VLP". It is given with an adjuvant called "Matrix-M". This is a substance to improve the body's response to a vaccination. RH5.2-VLP is being tested for the first time in humans in this trial. The Matrix-M adjuvant has been given to tens of thousands of people, with no major concerns, such as illness. The aim is to use this vaccine and adjuvant to help the body make an immune response against parts of the malaria parasite. This study will assess: 1. The safety of the vaccine in healthy participants. 2. The response of the human immune system to the vaccine. 3. The ability of the vaccine to prevent malaria illness (Group 2 only). We will do this by giving healthy adult participants (aged 18-45) three of the vaccines and/or expose participants to malaria infection at the Centre for Clinical Vaccinology and Tropical Medicine (CCVTM), Churchill Hospital in Oxford. We will then do blood tests and collect information about any symptoms that occur after vaccination. There will be 19 to 54 visits, lasting between 3 months to 2 years and 2 months.

A Study to Compare Two Dosing Regimens for a New Malaria Vaccine

Malaria is a major public health problem. There were around 240 million cases of malaria and 627,000 deaths worldwide in 2020. Most of the deaths are in children under five living in Africa. It is a major problem for those who live in affected areas and for travellers. There is a great need for a safe, effective malaria vaccine. This study is being done to evaluate an experimental malaria vaccine for its safety and also look at the body's immune response to the vaccine. The vaccine tested in this study is called and "RH5.1". This is given with an adjuvant called "Matrix-M". This is a substance to improve the body's response to a vaccination. The aim is to use the vaccines and adjuvant to help the body make an immune response against parts of the malaria parasite. This study will assess: 1. The safety of the vaccines in healthy participants. 2. The response of the human immune system to the vaccines. This will be achieved by giving participants three doses of the RH5.1 vaccines at two different dose levels (10 micrograms and 50 micrograms). One group will have 3 doses of 10 micrograms given at 0, 1 and 6 months whilst the other will receive 2 doses of 50 micrograms (at 1 and 2 months) followed by a 10 microgram dose at 6 months- known as a 'delayed fractional dose'. Blood tests and information about any symptoms will be performed/collected that occur after vaccination. Information from previous studies suggests that a delayed fractional dose improves the immune response to the vaccine, particularly in terms of the antibody response. Current prediction is that this improvement is due to the delay in dosing, rather than the reduction in dose, and this study will help to answer that. Having a vaccine at a single dose is important for efficient production and dosing for vaccines rolled out in national programs so being able to move away from 'delayed fractional dose' regimens to 'delayed final dose' regimens will be important for vaccine development.