View clinical trials related to Malaria.
Filter by:Plasmodium falciparum parasite clearance rates (PCRs) after oral artesunate treatment of patients with uncomplicated malaria were recently found to be significantly slower in Pailin (Western Cambodia) compared to Wang Pha (Eastern Thailand). This difference in PCRs has been attributed to different histories of artesunate drug pressure in the two areas. In Pailin, artesunate monotherapy has been used inappropriately for 30 years and is hypothesized to have selected for artemisinin-resistant parasites (slow PCRs). To investigate the potential contribution of human factors to the artemisinin resistance phenotype, we have identified a study site in Eastern Cambodia where artemisinin-resistant parasites are not believed to be present. The main aims of this study are to 1) determine whether the artemisinin resistance phenotype (i.e., a half-life longer than the 2-hour half-life observed in Wang Pha) is present in Eastern Cambodia, 2) determine whether hemoglobin E affects parasite clearance rates in vivo, 3) determine whether age-associated acquired immunity affects parasite clearance rates in vivo, and 4) identify parasite-heritable traits that are associated with slow parasite clearance rates in vivo. To meet these aims, we are conducting a prospective, longitudinal study to recruit Cambodian residents of Lumphat District in Ratanakiri Province who complain of fever and/or symptoms of malaria. Patients diagnosed with uncomplicated malaria will be treated with weight-based doses of artesunate given orally each day for 3 days followed by mefloquine given orally for 2 days. During this time, finger prick blood smears will be obtained every 6 hours until parasite density is zero. From these data, we will estimate parasite clearance rates using a half-life parameter. We will also collect parasitized red blood cell samples from malaria patients prior to antimalarial drug administration. These parasites will be tested in short-term in vitro culture experiments to determine their susceptibility to artemisinins and other antimalarial drugs.
Malaria is one of the major infectious diseases in the world with a tremendous impact on the quality of life significantly contributing to the ongoing poverty in endemic countries. It causes almost one million deaths per year, the majority of which are children under the age of five. The malaria parasite enters the human body through the skin, by the bite of an infected mosquito. Subsequently, it invades the liver and develops and multiplies inside the hepatocytes. After a week, the hepatocytes burst open and the parasites are released in the blood stream, causing the clinical phase of the disease. As a unique opportunity to study malaria immunology and efficacy of immunisation strategies, a protocol has been developed in the past to conduct experimental human malaria infections (EHMIs). EHMIs generally involve small groups of malaria-naïve volunteers infected via the bites of P. falciparum infected laboratory-reared Anopheline mosquitoes. Although potentially serious or even lethal, Plasmodium falciparum (P.falciparum) malaria can be radically cured at the earliest stages of blood infection where risks of complications are virtually absent. The investigators have shown previously, that healthy human volunteers can be protected from a malaria mosquito challenge by immunization with mosquito-bites under chloroquine prophylaxis (CPS immunization). However, it is unknown whether this protection is based on immunity directed towards the liver- or the blood stage of the disease. For future development of vaccines and understanding of protective immunity to malaria, it is important to investigate at which level protective immunity is generated by CPS immunization. Therefore, we aim to investigate whether CPS immunization confers protection to a blood-stage challenge.
This is a phase IV open label study assessing the safety and effectiveness of artemisinin derivatives-based combination therapy (ACT) when used on a large scale and under "real life" conditions.
The investigators hypothesize that schoolchildren treated with IPT using DP over one year of follow-up will have a different risk of clinical malaria compared to those treated with placebo.
The aim of the malaria vaccine program of the MVI/GSK partnership is to develop an efficacious malaria vaccine that is deliverable through the existing system, the Expanded Program on Immunization (EPI) of WHO. This study has been designed to: - Investigate the safety and immunogenicity of 7 infant immunization schedules of the experimental malaria vaccine integrated with an EPI regimen. - Investigate how to maximize the antibody response to the experimental malaria vaccine.
Malaria in pregnancy poses enormous public health challenges, contributing to significant maternal and infant deaths yearly. Adverse outcomes include maternal anaemia and low birthweight. Down regulation of cellular immunity increases pregnant women's susceptibility to malaria and mediate these adverse outcomes. The World Health Organization recommends treatment with artemisinin-combination therapy. Ghana uses quinine for malaria in first trimester pregnancies while artesunate-amodiaquine (AS-AQ) and quinine again are used in later trimesters. Recent amendments added artesunate-lumefantrine and dihydroartemisinin-piperaquine (DHA-PPQ) to the antimalarials used in the country. A high degree of safety and efficacy of DHA-PPQ is documented in several studies. DHA-PPQ, though not specified for use in pregnancy as of now, is accessible and available following its inclusion in the national malaria guidelines and may inadvertently be used to treat malaria in pregnancy. Paucity of data on DHA-PPQ use in pregnancy makes it pertinent to study its safety, tolerability and efficacy in pregnancy. We propose an open label, randomized controlled non-inferiority comparison of DHA-PPQ and AS-AQ for treatment of uncomplicated malaria in pregnancy in second and third trimesters to assess safety, tolerability and efficacy of DHA-PPQ. Outcomes of interest include PCR-corrected cure rates at days 28 and 42, maternal haemoglobin levels at days 14 and 42, prevalence of congenital abnormalities and pregnancy wastage. Proportions and percentages will be described at 95% Confidence Intervals and compared using chi-square tests. Parametric and non-parametric tests of significance will be applied as appropriate to determine significance of differences in outcomes between the treatment groups.
The purpose of this study is to describe the pediatric and adult patients (U.S. and foreign residents) diagnosed with malaria and treated with artemether-lumefantrine with regard to their demographics, including evaluation of their malaria immune status, treatment effectiveness, prior and concomitant medication use, and the occurrence of adverse events in association with artemether-lumefantrine treatment, based on the information collected in the CDC Malaria Case Surveillance Report Form.
Malaria is one of the major infectious diseases in the world with a tremendous impact on the quality of life significantly contributing to the ongoing poverty in endemic countries. It causes almost one million deaths per year, the majority of which are children under the age of five. The malaria parasite enters the human body through the skin, by the bite of an infected mosquito. Subsequently, it invades the liver and develops and multiplies inside the hepatocytes. After a week, the hepatocytes burst open and the parasites are released in the blood stream, causing the clinical phase of the disease. As a unique opportunity to study malaria immunology and efficacy of immunisation strategies, a protocol has been developed in the past to conduct experimental human malaria infections (EHMIs). EHMIs generally involve small groups of malaria-naïve volunteers infected via the bites of P. falciparum infected laboratory-reared Anopheline mosquitoes. Although potentially serious or even lethal, P. falciparum malaria can be radically cured at the earliest stages of blood infection where risks of complications are virtually absent. The investigators have shown previously that healthy human volunteers can be protected from a malaria mosquito (sporozoite) challenge by immunization with sporozoites (by mosquito bites) under chloroquine prophylaxis (CPS immunization). However, it is unknown how many mosquito bites are necessary to confer protection. Moreover, as all volunteers were protected in this study, no correlates of protection could be established. For future development of vaccines and understanding of protective immunity to malaria, it is important to investigate the lowest dose of CPS immunization that confers 100% protection and to find correlates of protection. Therefore, the present study aims to make the CPS immunization protocol more sensitive by lowering the number of infected mosquito bites, in order to study the underlying mechanisms of protection.
A longitudinal study on immune responses in relation to protection against clinical malaria episodes will be conducted in Apac District, Uganda. Three cohorts will be recruited: children 1 to 5 years of age (n=250), children 6 to 10 years of age (n=125) and adults 25 and above (n=125). After finger prick sampling (~300µL) and examination at enrolment, participants will be followed up for one year. Follow-up will include fortnightly active case detection and three-monthly cross-sectional surveys. Clinical malaria attacks and the associated clinical and parasitological parameters will be related to immunological profiles determined utilizing a protein microarray as a capture substratum to profile the humoral immune response against a vast number of parasite antigens. For individuals who experience a clinical malaria attack or who are diagnosed with high density parasitaemia (≥15,000 parasites/µL) during cross-sectional surveys, a 5mL blood sample is obtained to determine the diversity of parasite antigens in the population in relation to antigen recognition in the cohort.
A Phase IIa Exploratory, Open label, Single Dose Regimen, Multiple Dose Testing Clinical Study to Assess the Preliminary Efficacy, Tolerability and Pharmacokinetics of OZ439 in adult patients with acute, uncomplicated Plasmodium falciparum or vivax malaria mono-infection.