Active clinical trials for "Malaria"

The primary study hypothesis of the investigators is that administration of an iron supplement between meals at a dose like that used in the Pemba trial (~1 mg Fe/kg) during P. falciparum parasitemia will increase plasma non-transferrin-bound iron. A key subsidiary hypothesis is that iron administered with meals in amounts used in food fortification (~0.1 mg Fe/kg) will not produce plasma non-transferrin-bound iron. This research will be carried out at the Hospital for Tropical Diseases, Mahidol University, Bangkok, Thailand. The studies are intended to help understand how giving iron and folic acid to preschool children in Pemba, Zanzibar, Tanzania, (the "Pemba trial") in the doses recommended by the World Health Organization, could have resulted in an increase in hospitalizations and deaths. The investigators will examine the most likely explanation, that the dose of iron supplements used in the Pemba trial produced iron in the blood not bound to the usual carrier for iron (a protein called "transferrin"), that is called "non-transferrin-bound iron", abbreviated as NTBI. In children with malaria, this NTBI might favor the growth of malarial parasites or other causes of infection. At present, no studies have been carried out to see if NTBI is present after giving iron to patients with malaria. Using non-radioactive forms of iron (called "stable isotopes"), the investigators will study iron absorption and NTBI after giving a single dose of iron (like that used in the Pemba trial) one day after treatment for malaria has been started, while patients still have malaria parasites in the blood, and then again two weeks later, after the malaria has been cured. The investigators will study adults admitted to the Hospital for Tropical Diseases in Bangkok, Thailand, with malaria. For reasons of safety, the investigators have chosen to study adults in the hospital rather than children living in an area like Pemba but the results should also apply to children. The outcome of this research will help us design ways of safely giving iron in malarious areas to adults and children to prevent or treat iron deficiency.

GSK Biologicals is developing in partnership with the Malaria Vaccine Initiative at PATH a candidate malaria vaccine RTS,S/AS02 for the routine immunization of infants and children living in malaria endemic areas. The vaccine would offer protection against malaria disease due to the parasite Plasmodium falciparum and also would provide protection against infection with hepatitis B virus. Studies conducted using the formulation RTS,S/AS02A (0.25 ml dose) in children and adults have shown to be safe. Currently all intramuscular vaccines in the EPI schedule are administered at a dose volume of 0.5 ml and in this context, a new variant of RTS,S/AS02D (0.5 ml dose) formulation has been composed which has the same active constituents in the same quantities as in a 0.25 ml dose of RTS,S/AS02A. In this study, RTS,S/AS02D (0.5 ml dose) was compared to the existing formulation, RTS,S/AS02A (0.25 ml dose).

The investigators propose to assess whether an intervention to build capacity and improve delivery of drugs and diagnostics at government-run health facilities improves the health of children and quality of care delivered, as compared to 'standard care' currently available at health facilities, supplemented by services provided through the private sector and community-based interventions. The target population will be divided into 20 clusters, defined as the catchment area of lower-level public health facilities. Clusters will be randomized to the health facility intervention (HFI) or to standard care delivered from government-run health facilities, supplemented by services provided through the private sector and community-based interventions. The intervention is designed to address barriers to delivering quality care at health centers and will focus on three components: (1) training in-charges in health center management, (2) providing training to health workers in fever case management and patient-centered services, and (3) ensuring adequate supplies of artemether-lumefantrine and RDTs. Outcomes will be measured in three distinct populations: (1) cross-sectional surveys of children under 15 years randomly selected from households within the clusters; (2) a cohort of children under five randomly selected from households within the clusters and followed for 2 years; and (3) patients attending all government-run health facilities, including children under five and their caregivers participating in exit interviews on selected days every six months. The primary outcome of the study is prevalence of anemia in children under five.

At least three studies in sub-Saharan Africa have demonstrated a decrease in morbidity or mortality among HIV-infected adults who took daily cotrimoxazole (trimethoprim sulfamethoxazole) [CTX] prophylaxis. Because of the demonstrated beneficial effect, high tolerability and low cost of CTX, the United Nations Programme on HIV/AIDS (UNAIDS) recommends that HIV-infected persons with symptomatic HIV or depressed CD4 counts receive daily CTX. The effect of this recommendation on subsequent development of antimicrobial resistance to antifolates among important pathogens needs to be evaluated. The investigators measured the change in the prevalence of markers of antifolate resistance among P. falciparum, and the change in the prevalence of CTX resistance among S. pneumoniae, and E. coli in HIV-infected individuals receiving CTX daily prophylaxis. In addition, the investigators measured the change in the prevalence of naso-pharyngeal or oro-pharyngeal carriage of CTX resistant S. pneumoniae among children living in households where an HIV-infected adult was receiving CTX daily prophylaxis.

Highly subsidized first-line antimalarials (artemisinin combination therapy or ACT) are available over the counter in the private retail sector in most malaria-endemic countries. Overconsumption of ACTs purchased over the counter is rampant due to their low price, high perceived efficacy, and absence of diagnostic tools to guide drug use. The ultimate goal of the proposed work is to improve antimalarial stewardship in the retail sector, which is responsible for distributing the majority of antimalarials in sub-Saharan Africa. Through a combination of diagnosis and treatment subsidies and provider-directed incentives, this approach will align provider and customer incentives with appropriate case management and thereby improve health outcomes. The main objective of this study (Aim 2) is to test two key interventions in a random sample of private medicine retail outlets in Kenya. This will be a cluster-randomized controlled trial where the cluster is a private retail outlet that stocks and sells WHO quality-assured ACTs. This three-arm study will test 1) a consumer-directed intervention in the form of a diagnosis-dependent ACT subsidy, 2) both a provider-directed incentive for testing and a client-directed intervention in combination against 3) a comparison arm. Outlets in all three arms will offer malaria diagnostic testing to customers who wish to purchase one. Information for the primary and secondary outcomes will be collected during exit interviews with eligible customers. The primary outcome will be the proportion of ACTs sold to customers with a positive diagnostic test. The main secondary outcome will be the proportion of suspected malaria cases presenting to the retail outlet that are tested. Other secondary outcomes include adherence to the RDT result amongst those tested (defined as taking a quality-assured ACT following a positive test and refraining from taking an ACT following a negative test) and appropriate case management for all suspected malaria cases (proportion tested and adhered among all suspected cases).

This will be a single-centre, open label trial to determine the safety and feasibility of CHMI model using Plasmodium falciparum-infected cryopreserved erythrocytes administered to healthy Tanzanian adults with varying prior exposure to P. falciparum.

Measurement of the concentration of antimalarials in the blood of the general population helps estimating the overall drug pressure and is used in efficacy studies. The current sampling standard for drug measurement is plasma obtained by venous puncture. The use of a Dried Blood Spots (DBS) sampling strategy can make some aspects of field trials conditions easier, but concordance with usual venous sampling is not yet established. The current work will allow validating the concentrations of lumefantrine measured in the DBS samples collected during the field trials and validate the use of DBS for future studies. In addition, bearing in mind the substantial deployment of artemether-lumefantrine combinations supplies throughout most malaria endemic countries, this study may improve our understanding of lumefantrine and artemether distribution in the blood compartments and generate knowledge for further developing analytical methods for drug measurement. The overall purpose of this study is to validate the dried blood spots as a sampling method for the analysis of lumefantrine. The primary objective is to assess the concordance between lumefantrine plasma and dried blood spots (DBS) concentrations. The investigators also aim at describing lumefantrine's distribution in the different blood compartments: binding to plasma proteins, total in plasma, inside the red blood cells, total in whole blood.

Malaria is an infectious disease caused by a parasite that is passed to humans when an infected mosquito bites a person. About 3.4 billion people live in areas of the world where malaria is regularly found. In many countries, malaria is one of the leading causes of illness and death. Despite this, there are a limited number of drugs, called antimalarials, that can be used to treat malaria and increasing reports of resistance to existing antimalarials. The purpose of this research study is to test a new experimental antimalarial drug called SJ733 to first assess its safety, tolerability and blood levels in healthy adult volunteers. Single-dose, multi-dose and boosted-dose cohorts (both single and multi-dose) will be studied. The pharmacoenhancer (booster), cobicistat, will be given in combination with SJ733 in the boosted dose-cohorts. PRIMARY OBJECTIVES: To assess the preliminary safety and tolerability of escalating doses of antimalarial SJ733 in healthy human volunteers. To investigate the pharmacokinetic (PK) profile of escalating doses of antimalarial SJ733 and its metabolite in healthy human volunteers. To identify a dose of SJ733 that can be tested in a separate Phase 1b human malaria challenge study. To assess the preliminary safety and tolerability of SJ733 in healthy adult volunteers after multiple oral dosing. To assess the pharmacokinetics of SJ733 and its metabolite SJ506 after multiple dosing of SJ733 in healthy adult volunteers. To assess the preliminary safety and tolerability of escalating single oral doses of SJ733 in combination with cobicistat among healthy adult volunteers. To assess the pharmacokinetics of SJ733 and its metabolite SJ506 after single oral doses of SJ733 in combination with cobicistat among healthy adult volunteers. To assess the preliminary safety and tolerability of SJ733 in combination with cobicistat in healthy adult volunteers after multiple oral dosing. To assess the pharmacokinetics of SJ733 and its metabolite SJ506 after multiple dosing of SJ733 in combination with cobicistat among healthy volunteers. SECONDARY OBJECTIVE: To assess the impact of food intake on the pharmacokinetic profile of antimalarial SJ733.

Background. Overdiagnosis of malaria is widespread in health facilities throughout Africa, a situation that is unsustainable given the relatively high cost of artemisinin combination therapy (ACTs) compared to older antimalarials. In addition it often denies patients treatment for their actual illness and generates unreliable data for health planners. For these reasons the National Malaria Control Programme introduced revised guidelines for malaria diagnosis and treatment in 2006 restricting the recommendation for antimalarial treatment in patients over the age of 5 years to those with a positive blood slide or malaria rapid diagnostic tests (RDTs) result. To support this, RDTs will be introduced into primary care health facilities in Tanzania starting in 2009. The high accuracy of current rapid diagnostic tests (RDTs) provides the potential for a cost-effective solution to the problem of malaria overdiagnosis. However, RDTs with revised guidelines to restrict malaria diagnoses to RDT-positive patients have been unsuccessful unless accompanied by unsustainable levels of supervision and training. Primary objective. To conduct a trial of interventions directed at prescribers or prescribers and communities compared to control groups to improve adherence to national guidelines for prescription of antimalarial treatment when supported by RDTs in primary health care facilities in NE Tanzania. Methods All 60 participating health facilities will receive RDTs and basic training in their use and a copy of current NMCP/MOH guidelines for each prescribing staff member. A health worker intervention arm will, in addition, receive workplace-based interactive training and messages from senior staff A health worker-community arm will receive the same training as the health worker arm and in addition leaflets will be provided to RDT-tested patients providing information on the test and the treatment given. All training materials will be approved by NMCP in Tanzania as being consistent with current national guidelines but with the addition that prescribers will be asked to follow RDT results in prescribing for patients of any age This policy is in line with the most recent revision to WHO guidelines and is supported by NMCP in Tanzania. Study outcomes will be recorded through a 40% (2 days per week) exit survey of patients. Anthropological and economics studies will assess the costs and acceptability of interventions.

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. To date, however, only one such strain (NF54) has been broadly used in CHMI's. The purpose of this study is to compare the course of infections with 2 novel malaria strains to those with NF54 in human volunteers.