Active clinical trials for "Malaria"

Background: - Malaria is caused by small germs carried by mosquitoes. People can get malaria if an infected mosquito bites them. Malaria destroys red blood cells and reduces oxygen in the blood. Most malaria is mild, but severe malaria kills at least 660,000 people each year. About 75% of these are children in Sub-Saharan Africa, most under age 5. Researchers want to find a safe vaccine that helps prevent malaria. Objectives: - To see if a new malaria vaccine is well tolerated and effective. Eligibility: - Healthy adults 18 35 years old who are not pregnant and live in Mali. Design: Participants will be screened with medical history, physical exam, and blood test. They will also have an ECG. Soft electrodes will be stuck to the skin. A machine will record the heart s electrical signals. Study participation will last about 1 year. Participants will be randomly placed in 5 groups. Some will get 2 doses of the PfSPZ vaccine weeks apart; some will get 3 or 5 doses of vaccine; some will get 3 or 5 doses of placebo. Doses will be given through a needle in the arm directly into the bloodstream. Then participants must stay at the clinic for 2 hours. After each dose, participants will return to the clinic several times for blood tests and physical exam. A week before the first dose and 2 weeks after the last, participants will take a full course of anti-malaria drugs. If a participant gets malaria during the study, they will take another course of anti-malaria drugs.

The scaling up of Long Lasting Insecticidal Nets (LLIN) and the expansion of Indoor Residual Spraying (IRS) has contributed to a significant decrease of malaria worldwide. However these control methods tackle only indoor and night biting vectors. The proportion of transmission occurring outdoors and before sleeping hours or so-called "residual transmission" is steadily increasing and may compromise the effort towards malaria elimination. The purpose of this study is to raise evidence on the effectiveness of mass use of topical repellents in addition to LLINs in controlling malaria infections. A multidisciplinary approach will be used to collect information on the most important factors that contribute to the successful reduction of "residual malaria transmission". In a first objective the epidemiological efficacy of repellents on prevalence of malaria carriers and malaria incidence will be assessed. To achieve this goal 98 communities will be randomly assigned to one of two treatment arms (LLIN and LLIN + repellent). Within a community a cross sectional random sample of 65 people will be drawn at the beginning and the end of the malaria season to obtain an estimate of the malaria prevalence. The second objective will handle the entomological efficacy and persistence of the topical repellent on malaria vectors. And lastly the acceptability, adherence and adequacy of the topical repellents will be studied in a third objective.

Malaria transmission is falling in some parts of Africa as bed nets and anti-malarials become more widely available. However, transmission still persists and it appears that additional control measures are required. The leading malaria vaccine candidate in development is RTS,S which has efficacy against clinical malaria measured at 30-50% in the field. This partial protection might be enhanced by combination with other components. The other vaccination approach that has produced repeatable efficacy in humans is the use of viral vectors to induce T cell responses. Previous attempts with this vaccine approach have been effective in challenge studies in Oxford, but ineffective in the field, probably because of reduced immunogenicity with previous vector platforms. Recently, studies in Oxford, Kenya and the Gambia have shown higher levels of immunogenicity by using a chimpanzee adenovirus (ChAd63) followed by an attenuated vaccinia virus (modified vaccinia Ankara) to deliver the pre-erythrocytic antigen, multiple epitope string with thrombospondin- related adhesion protein (ME-TRAP). The increase in immunogenicity has lead to sterile protection in 3 out of 14 volunteers and partial protection in 5 out of 14 volunteers in challenge studies. The investigators propose a Phase 2b study of 120 healthy adult men in Senegal. The investigators will assess the efficacy and further evaluate the immunogenicity and safety profile of the vaccine regimen. The investigators also intend to assess the correlates of efficacy and natural immunity.

The program's overall objective is to assess the impact of a package of interventions aimed at reducing malaria-related mortality and morbidity in pregnant women and newborns by ensuring access to a package of interventions designed to optimise the detection and treatment of malaria during pregnancy as well as improving the early detection and treatment of malaria during the third trimester.

The proposed trial will evaluate whether relatively non immune populations in endemic countries can be effectively infected with aseptic, purified, cryopreserved sporozoites (PfSPZ Challenge) given intradermally.

The purpose of this study is to conduct long-term surveillance for efficacy, safety and immunogenicity of the GSK Biologicals RTS,S/AS01E candidate Plasmodium falciparum malaria vaccine in infants and children in Africa following a primary vaccination series (NCT00866619). No new subjects will be enrolled in this extension study.

The purpose of this study is to assess two new malaria vaccines, ChAd63 RH5 and MVA RH5, at different doses and alone or in combination. The study will enable us to assess the safety of the vaccines and the extent of the immune response in healthy volunteers. We will do this by giving volunteers one or two vaccinations, doing blood tests and collecting information about any symptoms that occur after vaccination. This is the first trial to use these vaccines in humans.

This trial will evaluate whether relatively non-immune populations in endemic countries can effectively generate significant cellular and humoral immune responses that confer protection against P. falciparum infection after inoculation of aseptic, purified, vialed, metabolically active, non-replicating (live, radiation attenuated) Plasmodium falciparum sporozoites (PfSPZ Vaccine) administered intravenously (IV).

The purpose of this study is to assess the safety, tolerability and immunogenicity of two dose levels (1x10^10 and 5x10^10 virus particles (vp)) of the adenovirus serotype (Ad) Ad35.CS.01/Ad26.CS.01 prime-boost malaria candidate vaccine, followed by an evaluation of the protective efficacy of the higher dose level in an experimental malaria challenge. The study will be in 3 phases: a dose escalation / vaccination phase in which both dose levels will be tested a malaria challenge phase in which only subjects receiving the Ad35.CS.01/Ad26.CS.01 5x10^10 vp dose level, together with six infectivity control subjects, will be exposed to experimental challenge with Plasmodium falciparum a long term follow up phase in which all subjects who received active vaccine from both dose levels and/or malaria challenge will be included

This study is being done to assess the possibility of the potential integration of malaria vaccine into the EPI regimen. It will evaluate whether the malaria vaccine is safe and immunogenic in infants aged 6 to 10 weeks at first dose, when co-administered with other EPI vaccine antigens. The Protocol Posting has been updated in order to comply with the FDA Amendment Act, Sep 2007.