Active clinical trials for "Malaria"

This was a single-center study using induced blood stage malaria infection to characterize the activity of ACT-451840 against early Plasmodium falciparum blood stage infection

Background: Malaria remains a major global health problem. Malaria is spread by the bite of mosquitos. Africa is the region of the world where most people get malaria. Sanaria PfSPZ Challenge is a malaria vaccine. Researchers want to see if the vaccine combined with partner drugs can help protect against malaria. Objective: To test if injections with 3 monthly doses of Sanaria PfSPZ Challenge, combined with either pyrimethamine (PYR) or chloroquine as a partner drug, is safe, tolerable, and effective. Eligibility: Healthy people ages 18-50 years who live in Bancoumana, Mali, or nearby Design: Participants will be screened with the Malaria Comprehension Exam to check their understanding of the study. They will have a medical history. They will have a physical exam. They will have blood tests, urine tests, and heart tests. Participants will join either the pilot study or the main study. Participants will be assigned to groups. Depending on their group, they will get at least one injection of either a placebo or the vaccine. They may have up to 3 vaccines, 4 weeks apart. The injection will be into a vein with a needle. Participants will also take pyrimethamine or chloroquine by mouth. They will also take standard doses of antimalarial drugs by mouth. Participants will have blood tests throughout the study. Participants may develop a rash or injection site reaction. If this happens, photos of the site may be taken. Participants will be observed for infection for many days after the injections.

A single-centre Phase 1b study to assess the safety, tolerability, pharmacokinetic profile, and antimalarial activity of single doses of coadministered artefenomel (OZ439) and piperaquine phosphate (PQP) against early Plasmodium falciparum blood stage infection in healthy adult volunteers.

Controlled human malaria infection (CHMI) is an important tool for the assessment of the efficacy of novel malaria vaccines and drugs prior to field trials. CHMI also allows for the evaluation of immunity to malaria and parasite growth rates in vivo and thus allows for the assessment of the natural acquisition and loss of malaria immunity. This may be particularly useful in individuals from endemic areas with changing levels of exposure and immunity to malaria. Thus, CHMI in individuals with prior exposure to malaria could be a valuable tool to accelerate malaria vaccine development and inform malaria control programs of changing immunity levels and related disease presentations. In this trial, the investigators intend to study the effect of pre-exposure to Plasmodium falciparum (Pf) on parasite kinetics, clinical symptoms and immunity after CHMI by PfSPZ Challenge in Gambian adults. Based on a well-defined sero-profile representing the extremes of current malaria exposure in The Gambia, two cohorts will be identified to study the impact of naturally acquired immunity on susceptibility for a Controlled Human Malaria Infection.

This was a randomized, subject and investigator-blinded, placebo-controlled, single and multiple ascending intravenous (iv) dose study in healthy subjects to assess the safety and tolerability of KAE609 given in the vein.

This study is designed to characterise P. falciparum transmission intensity in subjects aged ≥6 months and <10 years by measurement of P. falciparum parasite prevalence, and to estimate the use of malaria control interventions at some centres selected for the EPI-MAL-002 and EPI-MAL-003 studies in sub-Saharan Western Africa.

This study is a randomized clinical trial designed to compare the susceptibility of naive and pre-immune volunteers to infectious challenge with viable Plasmodium vivax sporozoites. The term preimmune hereafter denoted only previous experience with infection by this parasite and not a definite state of immunity to malaria infection. The study hypothesis is that pre-immune volunteers present a delayed onset of malaria clinical and parasitological manifestations when compared to naive individuals. The development of this study will establish a protocol for evaluating the effectiveness of vaccine candidates against P. vivax in subsequent Phases IIa and IIb clinical trials.

This is a randomized, double-blind, controlled, which seeks to compare two groups of volunteers (naive and previously exposed to malaria) who were made 3 immunizations with a synthetic derivative of the CS protein of Plasmodium vivax in order to determine their protective efficacy. Then volunteers will be subject to an infectious challenge to assess the infectivity of gametocytes in the blood early stage of P. vivax in Anopheles albimanus mosquitoes.

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.

The purpose of this study is to perform laboratory based studies to determine if the growth and development of the malaria parasite is effected by iron status of its host (the person infected with the malaria parasite). Iron deficiency affects over 500 million people including many pregnant women and children from areas of the world that are plagued by malaria. Some population based studies have suggested that iron deficiency protects people from getting malaria and this has raised questions about the wisdom of public health policies that provide universal iron supplementation in countries where malaria is common. We will use red blood cells and sera from patients with iron deficiency anemia, hereditary hemochromatosis and normal individuals who are taking iron supplements to look at this question in a very systematic way. This study should provide information for or against a possible mechanism by which iron deficiency may affect the malaria parasite. The results will contribute to efforts to develop evidence-based public health policies on iron supplementation policies in malaria-endemic areas. There are three different types of individuals involved in this study (1) people with iron deficiency anemia who will be taking iron supplementation (2) people without iron deficiency anemia who will be taking iron supplementation and (3) people with a condition called hereditary hemochromatosis who have an excess of iron in their bodies.