Active clinical trials for "Malaria"

The proposed trial design has been developed to answer several questions related to the nature of RTS,S vaccine efficacy in African adults that may be influenced by concurrent and/or past P. falciparum infection leading to a state of immunologic hypo-responsiveness. The proposed study design encompasses five groups. Three groups (Groups 1, 2, and 3) will be administered RTS,S/AS01E on a 0, 1, 7 month schedule with Dose 3 delivered as a 1/5th fractional dose. Two groups (Groups 4 and 5) will be administered a comparator vaccine on a 0, 1, 7 month schedule.

This is a clinical study to assess the safety of primary, secondary and tertiary blood-stage controlled human Plasmodium falciparum malaria infection of healthy malaria-naïve UK adults, as well as to evaluate any effect of prior exposure to a blood-stage controlled human malaria infection (CHMI) on the parasite multiplication rate. As a secondary objective, the immune response to primary, secondary and tertiary P. falciparum blood-stage infection, as well as gametocytaemia, will also be assessed.

The present study assesses the pharmacokinetic profile of Ivermectin (IVM) in healthy human volunteers and aims to create a physiologically-based pharmacokinetic model. Planned indication is the prevention of malaria transmission.

Background: Malaria is caused by a parasite (a type of germ called P. vivax) that is carried by mosquitoes. The disease is transmitted to people when they are bitten by infected mosquitoes. To make drugs and vaccines for malaria, researchers need malaria-infected blood. Plasmodium vivax cell cultures are currently not cultured in vivo, and thus establishing a blood bank from P. vivax infections will be vital for future research. Objective: The goal of this study is to infect people with early-stage malaria, then collect infected blood samples to store in a cell bank for future use. Eligibility: Healthy adults ages 18-50 who will not be living alone during the study period. Design: Participants will be screened with a physical exam, heart health test, and medical history. They will have blood and urine tests. They will take a mental health survey. They must pass an exam to prove they understand the study. Participants will have red blood cells infected with P. vivax injected into an arm vein. They will be observed for side effects. They will get a thermometer to measure their temperature at home. For the next 3 days, they will be monitored via phone call or text. Starting on day 4 after the infection, they will have daily study visits to give blood samples. They will likely develop symptoms of malaria, such as fever, chills, headache, and muscle pain. Participants will be admitted to the hospital for 2-3 days when either they develop symptoms or the daily blood tests detect a certain amount of parasites. Once malaria is confirmed, a sample of their blood will be collected for the cell bank. Then they will be treated for malaria with oral medication that will cure the infection. Those who do not develop malaria will begin treatment after 15 days. Participants will have follow-up visits 28 and 90 days after infection. Participation will last for 3-5 months.

Malaria is a protozoan infection transmitted by anopheline mosquitoes. The most severe forms are caused by Plasmodium (P) falciparum and to a much lesser extent by P. vivax. Although the interest in research on malaria has increased during the last years, yet little research is conducted on the "neglected" malaria species P. ovale and P. malariae. P. ovale being first described in 1922, it still remains unclear whether it displays dormant pre-erythrocytic liver stages, so called hypnozoites, or not. Primaquine, the only marketed drug with liver stage activity at present, can cause severe hemolysis in glucose-6-phosphate dehydrogenase (G6PD) deficient persons and methemoglobinemia. Because G6PD is widely spread in Central Africa, it is important to explore whether additional intake of liver-active medication is really needed and on this account further research to investigating new treatment options with liver stage activity should be conducted. While, due to widespread resistance, treatment recommendations for P. falciparum and mixed infections have switched from chloroquine to the safer applicable artemisinin-based combination therapies (ACTs), World Health Organization (WHO) guidelines still suggest chloroquine as first line treatment for P. malariae and P. ovale mono infections. Further studies assessing alternative treatment options are largely missing. Summing up the current situation for both topics shows the need for further research. Therefore this study aims to assess the evidence and characterize the frequency of relapses in P. ovale infections with respect to differences between its subspecies as well as the effectiveness of the ACT artemether-lumefantrine in P. malariae and P. ovale mono- and mixed infections.

This project aims to test an innovative, sustainable financial incentive designed to reduce the number of non-malarial fevers that are treated inappropriately with antimalarial drugs.

This study aims to assess the safety and effectiveness of four new candidate malaria vaccines; ChAd63 CS, ChAd63 ME-TRAP, MVA CS & MVA ME-TRAP. These vaccines consist of viruses (ChAd63 and MVA) which have been genetically modified so (i) they cannot replicate in humans and (ii) they include parts of the malaria parasite; Plasmodium falciparum (CS and ME-TRAP). The hope is that these vaccines will induce immune responses in vaccinees that are able to prevent malaria. This proposed study will compare how effective ChAd63-MVA CS is at preventing malaria infection in UK volunteers following malaria challenge compared to ChAd63-MVA ME-TRAP. The study will be conducted at the University of Oxford's Centre for Clinical Vaccinology and Tropical Medicine (CCVTM), Oxford, UK and the Wellcome Trust Clinical Research Facility in Southampton, UK. The malaria challenge will take place at the insectary at Imperial College (Infection and Immunity Section) in London, UK.

An effective vaccine against malaria is urgently needed to combat the scourge of this disease. Before candidate vaccines can be tested in endemic countries, they are first tested in human volunteers in so-called Controlled Human Malaria Infections (CHMI's). Ideally, a candidate vaccine should be tested against multiple strains of malaria, representative of the disease's global distribution. Recently we compared, for the first time, infections with the novel malaria strains NF135 and NF166 to those with the broadly-used and well-characterised strain NF54. The purpose of the current study is to optimise the course of infections with these novel strains by determining the minimum number of infectious bites necessary to reliably induce a malaria infection.

There are compelling medical and public health reasons to reduce unnecessary consumption of antimalarials and strong evidence to support the use of RDTs in malaria case management. The primary study hypothesis to be tested is that clients who know they will receive a subsidy conditional on a positive test are more likely to opt for testing before deciding which drug to buy. The primary endpoint is whether subjects choose to be tested for malaria with a rapid diagnostic test. The secondary endpoint is whether they purchased an artemisinin combination therapy (ACT) or not. The primary outcome of interest is to compare the proportion of participants who choose to receive a free malaria diagnostic test when they can receive a subsidy for a discounted drug conditional on a positive test (Group A compared to Group B) compared to those without the offer of a conditional subsidy. The investigators will use an experimental design that randomly assigns clients to one of four groups. Field workers will canvas households in the study area looking for individuals who have fever or history of fever or illness in the last 24 hours (current illness) who have not yet taken drugs or sought treatment outside the home. Clients who meet the inclusion criteria and give verbal consent to participate will be randomly assigned to one of the four groups. They will be given the location and contact information for their local community health worker who can provide a malaria rapid diagnostic test if they choose to be tested. They will also complete a survey tool. One week later, the field worker will return to interview the participant and determine whether they were tested, what action they took for their illness, what medicine they purchased and how much they paid. The investigators will summarize clients' choice by the four randomized study groups.

The study is designed to establish infectivity of Plasmodium falciparum sporozoites (PfSPZ) via intravenous (IV) administration in three groups with different malaria immunity-status: Adults with a history of lifelong malaria exposure without sickle cell trait (HbAA) Adults with a history of lifelong malaria exposure with sickle cell trait (HbAS) Adults without previous malaria episodes without sickle cell trait (HbAA) Initially a dose of 3,200 PfSPZ will be given and the time until thick blood smear positivity after challenge will be assessed. If in any of the groups with a history of lifelong malaria exposure, 50% or less of individuals become thick blood smear positive during the 28 days post injection of PfSPZ Challenge, the dose will be increased 4-fold to 12,800 PfSPZ in this group.