What is the purpose of this trial?
Malaria is a major global health problem, transmitted by the bite of an infected mosquito, with more than 200 million cases and over 400,000 deaths each year. There is a great need for a safe, effective malaria vaccine as other preventive measures and treatments remain inadequate.Plasmodium vivax (P. vivax) is the second commonest type of malaria parasite and can also relapse at a later date if not properly treated. It is very hard to grow in the laboratory so there is limited knowledge of how it causes disease and how to make a vaccine that works against it. By infecting volunteers with P. vivax by mosquito bite under controlled conditions and taking blood at regular intervals we can gain important information about the growth of the parasite and of the immune responses the body makes to it. This may help us make an effective vaccine against P. vivax in the future. While similar human infection studies have been done with P. vivax outside Europe, this is the first time this has been done in Europe. We are therefore hoping to demonstrate that this is safe in a small pilot study before progressing to larger studies.
What does the study involve?
The study involves exposing you to malaria infection by allowing P. vivax malaria-infected mosquitoes to bite under carefully regulated conditions. We will follow you closely with regular blood tests to observe if and when you develop malaria. Once malaria infection has been confirmed (by detecting parasites in the blood) we will admit you to our clinical research bay at the Churchill hospital, continue to monitor you closely and take about half a pint (250 mL) of blood. We will then immediately start you on antimalarial treatment, in order to clear the infection. The 250 mL (P. vivax-infected) blood donation will be stored for future efficacy testing of candidate vaccines against P. vivax, and ultimately contribute to the development of a safe and effective P. vivax malaria vaccine regimen.
You will be required to complete 2 courses of malaria treatment (total of 17 days of tablets) and attend for regular clinic visits.
Is there any reimbursement for the trial?
Yes, you will be reimbursed at a set rate (£3,255) for your time, inconvenience and travel. Full details of reimbursement can be found in the trial information sheet.
What are the advantages of taking part?
You will not benefit directly from participation in this study. However, it is hoped that the information gained on the immune response to P. vivax from your blood samples should inform on future vaccine design. In addition, the blood inoculum generated from this study will allow efficacy testing of future candidate vaccines against P. vivax, and ultimately contribute to the development of a safe and effective P. vivax malaria vaccine regimen that can prevent malaria infection and disease in those living in areas where malaria is common and in travellers to those areas. At present, there is no malaria vaccine licensed anywhere in the world.
Are there any risks from taking part in the study?
All risks within this study have been well managed provided that you return for follow-up as in the information sheet.
What will happen if I don’t want to carry on with the study?
If at any time after agreeing to participate you change your mind about being involved with this study, you are free to withdraw without giving a reason. Your decision will not result in any penalty, or loss of benefits to which you are otherwise entitled. However, if you wish to leave after malaria challenge then you must take the treatment course of Riamet (antimalarial drug) or an agreed alternative, followed by a 14-day course of Primaquine to prevent any relapse. The consequences of untreated malaria infection are potentially very serious. Your compensation would be paid as a proportion of the total compensation according to the length of your participation.