Active clinical trials for "Malaria"

The purpose of this study is to learn more about vivax malaria in very young children, how the growth of children is affected by malaria infections, and how inherited traits protect children from getting malaria. Participants will be 266 children 24 months of age or younger who live in certain villages in East Sepik Province, Papua New Guinea, where malaria is very common. The study also will find out how malaria spreads in the area. By learning how and when a child develops resistance to vivax malaria, researchers can try to find ways to help people from getting it. And, they can get a better understanding of how inherited traits influence all types of malaria infections. In this study, the parent and child will be visited by the study team or health workers every week to check health and bednet use. Every 2 weeks, the study team will take a small blood sample to check for malaria and take measurements to study the child's growth. Participants will be followed for up to 2 years.

This study will assess the efficacy of Pyramax administered for three-day, two-day or one day, in clearing a P. falciparum infection in asymptomatic carriers. .

Investigators are conducting this study due to recent reports of many of existing malaria drugs becoming less effective for treatment of malaria. The drugs may not always kill all the parasites, therefore not all patients with malaria are being cured. The main objective of the study is to find out which malaria drugs and what drug combinations are still effective in Cambodia, an area of multi-drug resistance where 4-5 artemisinin-based combination therapies have shown inadequate response, below that established by the World Health Organization (WHO). New drug combinations (taking more than one drug for malaria at the same time), as long as well tolerated, can provide cure in patients that harbor parasites not responsive to standard first-line medications. Human genetic testing will be done to identify patients who may have suboptimal response to treatments and to study the differences in human gene expression to explain why some persons are at higher risk of complications during treatment. Markers of drug resistance to commonly used antimalarial drugs will also be evaluated and shared with national malaria program (CNM) to better guide future malaria treatment decisions in Cambodia.

A comparison of Malaria events (symptoms and signs of malaria) experienced by subjects infected with PfSPZ Challenge (NF54) vs. PfSPZ Challenge (7G8).

At the end of 2012, the Institute of Tropical Medicine in collaboration with National Institute of Malariology Parasitology and Entomology (NIMPE) conducted a study in Quang Nam province, central Vietnam, to assess the efficacy of the national DHA-PPQ regimen for the treatment of uncomplicated P. falciparum malaria infections, both in adults and in children. Results showed that about 30% of the study participants were parasitaemic at day 3. Parasite clearance rate was estimated at 6.2h, which was comparable to figures from Pailin, Cambodia, where artemisinin resistance were previously reported . However, results from this study have to be interpreted bearing in mind that: (i) the age-based drug dosing scheme used has been criticized as insufficient to clear parasites and (ii) DHA-PPQ drugs used (Artecan™), Vietnam, are not produced under Good Manufacturing Practices (GMPs). However, those results prompted the NMCP and WHO to declare Quang Nam, Binh Phuoc, Dak Nong, and Gia Lai provinces as a "Tier I area" (credible evidence of artemisinin resistance) in May 2013. By end of 2014 a fifth province, Khanh Hoa, was declared Tier I (Dr Hong, Personal Communication). Except for the south-eastern province of Binh Phuoc, artemisinin resistance has never been confirmed with an artemisinin based monotherapy in Central Vietnam. Therefore, in order to confirm artemisinin resistance in Central Vietnam , a study with oral artemisinin-based monotherapy, using WHO prequalified AS and DHA-PPQ and recommended dosing scheme of 4mg/kg/day for AS and DHA, is needed. In the arm where study participants are treated with 3 days of AS monotherapy, treatment will be followed by an additional 3-day course of DHA-PPQ to effectively clear all parasites. The aim of the present study is to confirm artemisinin resistance in Central Vietnam by assessing P. falciparum clearance time and rate after AS monotherapy (WHO recommended dosage). The investigators will conduct a two-arm open label, randomized study, with one arm receiving AS monotherapy for 3 days + 3-day of DHA-PPQ, and a second arm receiving 3 days of DHA-PPQ.

This study specifically seeks to provide data on the safety, tolerability and pilot efficacy of short course, high dose primaquine treatment in Papua New Guinean children aged 5-10 years, in a cross-sectional study design. Community screened asymptomatic cases and/or cases of clinically diagnosed malaria admitted to the out-patient units of the health center, will be screened for Glucose-6-phosphate dehydrogenase deficiency (G6PD) and malaria illness by rapid diagnostic test and P. vivax infection confirmed by light microscopy. Following treatment with artemether-lumefantrine (Coartem), G6PD normal children will be enrolled into the study and followed for 2 months. Primaquine treatment will be allocated to study participants in a step-wise design; firstly receiving the current 14 day treatment regimen of 0.5 mg/kg total dose (n=40); secondly, a 7 day treatment regimen receiving a total dose of 1.0 mg/kg/day; then thirdly, receive 1.0 mg/kg twice daily dose (bd) for a total of 3.5 days, should the 7 day treatment prove to be safe and well tolerated. In addition to this dose-escalation study, the pharmacokinetic profiles of single doses of 0.5 mg/kg and 1.0 mg/kg will be determined using an intensive sampling protocol, in children aged 5-10 years. The pharmacokinetic profiles obtained by this sub-study will be essential for modeling the population pharmacokinetic data obtained from the dose-escalation study. As there is currently no data on the safety, tolerability and efficacy of primaquine in children, the present study will validate previous observation and contribute to the knowledge of primaquine as a treatment for liver stages of Plasmodium vivax infection.

Plasmodium falciparum malaria is a major cause of morbidity and mortality in tropical and sub-tropical areas worldwide. Repeated P. falciparum infections in endemic areas induce protective immunity, thus providing optimism that an effective malaria vaccine can be developed. Key to the development of such a vaccine is an understanding of the immune mechanisms underlying protection and the longevity of these responses in the absence of continuous P. falciparum exposure. Anecdotal evidence suggests clinical immunity to malaria wanes within months to years after an immune individual leaves an endemic area. A detailed, systematic description of the quality and longevity of the P. falciparum-specific humoral and cellular immune responses in such individuals over time in the absence of ongoing exposure is lacking. This protocol will attempt to fill this knowledge gap through comprehensive longitudinal immunological analyses of two populations of healthy adult volunteers: 1) naive travelers returning from malaria endemic areas recently treated (within 2 weeks) for acute P. falciparum malaria and referred from hospitals in the metropolitan Washington DC area; and 2) immigrants from malaria endemic areas living in the metropolitan Washington DC area with serologic evidence of past P. falciparum exposure. In both groups, venipuncture and possibly apheresis will be performed for the isolation of plasma, RNA and peripheral blood mononuclear cells (PBMCs) which will be analysed to understand the components of innate and adaptive immunity to malaria. Na(SqrRoot) ve travelers returning from malaria endemic areas recently treated for acute malaria will undergo venipuncture at enrollment, then once every 2 weeks for 2 months, then every 3 months for 1 year, and then every 6 months for up to 5 years. Immigrants will be seen every three months for one year and then every six months for up to 5 years. All subjects who return to the U.S. from a malaria endemic area will be evaluated within two weeks of return for repeat venipuncture and will restart the same sequence of blood draws as naive travelers. Optional apheresis will be performed on both na(SqrRoot) ve travelers and immigrants at enrollment, at 1, 6, and 12 months, then yearly therafter. The primary objective is to estimate the quality and longevity of P. falciparum-specific humoral and cellular immune responses in the absence of ongoing P. falciparum exposure in both returned na(SqrRoot) ve travelers and immigrants. The secondary objective is to compare the P. falciparum-specific humoral and cellular immune response in na(SqrRoot) ve travelers and immigrants to individuals in malaria-endemic areas enrolled in ongoing LIG protocols in Mali. ...

The primary objective of the study is to demonstrate and quantify the protective efficacy (PE) of spatial repellent products in reducing the incidence of malaria infection in human cohorts. The null hypothesis (H0) is that there is no difference in malaria incidence between intervention and control arms.

Background: Malaria, a disease transmitted by mosquitoes, affects millions of people with the highest frequency, morbidity, and mortality in infants and young children. Plasmodium falciparum and Plasmodium vivax, the most common and severe forms of malaria, have host- and stage-specific proteins that can induce immunity to the disease. Vaccines against stages that infect mosquitoes will prevent the spread of malaria. Researchers have developed a vaccine composed of a single protein, Pfs25, to induce antibodies in the human host that will be ingested by the mosquito and prevent the malaria parasite from reproducing and stop transmission of the disease. Because Pfs25 is present only in the mosquito, humans do not develop antibodies to this antigen even in endemic areas. Repeated injections of this vaccine may be necessary. Objectives: - To establish the safety and optimal dosage of a malaria vaccine developed with the Pfs25 protein. Eligibility: - Healthy adults between 18 and 49 years of age who have never had malaria or received a malaria vaccine. Design: Two doses of Pfs25 conjugate (10 micrograms and 25 micrograms) will be evaluated in this study. Participants will receive only one of these doses in order to provide the best scientific data for evaluation. To determine eligibility, participants will provide a medical history and have a physical examination, and will provide blood and urine samples to test for HIV/AIDS, hepatitis, and other conditions that would prevent them from participating. Eligible participants will receive one injection of the vaccine. The injection will be followed 30 minutes later with a temperature reading and an inspection of the vaccine site. Upon leaving the clinic, participants will receive diary forms, a digital thermometer, a ruler, and instructions about how to take their temperature and to measure redness and swelling (if any) at the injection site. About 6 hours later, and daily for 3 days, participants will take their temperature at home and examine the injection site. Participants will be examined at the clinic at 48 to 72 hours and on day 7 after an injection. A blood sample will be taken 1 week after immunization. - Participants will receive a second and third injection of the same vaccine at 6-week intervals, and will follow the same recording procedure given above. Further blood samples will be taken at regular intervals for up to 12 months after the vaccination, as directed by the study researchers.

The purpose of this study is to compare the efficacy and safety of two antimalarial drug regimes, namely amodiaquine versus amodiaquine-artesunate, in the treatment of children with uncomplicated malaria. Also, genetic host factors which might influence efficacy and/or safety will be examined.