View clinical trials related to Malaria, Vivax.
Filter by:The proportion of malaria that is the Plasmodium vivax species is increasing in Indonesia. Reducing vivax malaria will require innovative solutions to cure both the blood and liver stages of the disease. This study will evaluate of the feasibility of implementing point-of-care glucose-6-phosphate dehydrogenase deficiency (G6PD) testing. This will be followed by high dose, short course primaquine treatment regimens for patients with vivax malaria, and combined with patient education, surveillance, and pharmacovigilance. We plan to implement the study at 6 health facilities across Indonesia using a staged before-and-after study, with a mixed method evaluation.
Significant gains have been made in reducing the overall burden of malaria worldwide, however these have been far greater for Plasmodium falciparum than P. vivax. P. vivax remains a major obstacle to malaria control and elimination efforts, largely due to its ability to form dormant liver stages (hypnozoites) that allows it to escape detection and treatment. Importantly, they are susceptible only to 8 aminoquinolines such as primaquine. However, primaquine is associated with risk of haemolysis in individuals with a genetic condition, called glucose-6-phosphate dehydrogenase (G6PD) deficiency. Additionally, the recommended 14-day prolonged treatment regimen is associated with poor treatment adherence, hence ineffective primaquine treatment. Innovative solutions to the radical cure of both the blood and liver stages of P. vivax are urgently required. The PNG National Department of Health has requested a pragmatic study of the feasibility and cost-effectiveness of implementing point-of-care G6PD testing followed by high-dose, short-course primaquine treatment regimens for patients with P. vivax malaria. This revised case management is to be combined with practicable enhancements to patient education, supervision, malariometric surveillance and pharmacovigilance. This will be a before-after longitudinal health facility-based study implemented at Napapar and Mugil health centres and Baro and Wirui clinics. A staged approach for the implementation of the revised case management strategy will be used, including patient education and counselling, community-based clinical review, with mixed methods evaluation.
In this area of Greater Mekong Subregion (GMS), vivax malaria is the most common kind of malaria. It can stay very long in the liver, and come out later to make another episode of illness. This can happen many times even without a mosquito bite. Only 8-aminoquinoline drugs can kill the liver forms of the malaria parasite. One of these drugs is called primaquine, and it has been used all over the world for a long time. There is now a new formulation of this 8-aminoquinoline drug called tafenoquine that can also treat the malaria in the liver. The main benefit of this drug is that it is a single dose, which makes much convenient for the patients as well as for the malaria control program than conventional 14 days of primaquine. Recent research suggests that ACT (Artemisinin Combination Therapy) may antagonise the efficacy of tafenoquine (Baird et al. 2020 ASTMH Annual Meeting) . This could prevent the use of tafenoquine in areas with chloroquine resistant P. vivax parasites where national malaria programmes recommend ACTs for vivax malaria. Also, currently recommended tafenoquine dose is sub-optimal: 300 mg dose proved significantly inferior to low dose primaquine in a meta-analysis of the phase 3 studies when restricted to the Southeast Asian region (Llanos-Cuentas et al. 2019 NEJM; Watson et al. 2022a Elife). A tafenoquine dose of 450mg is predicted to provide >90% of the maximal effect. The objective of this research is to find out whether 450 mg dose of tafenoquine can be combined effectively with ACT providing a short course treatment for P. vivax malaria.
The investigators are proposing a new malaria control strategy to reach the group of garimpeiros not reached by the usual actions of the health services. As it is a complex strategy, several evaluation mechanisms have been designed. The main characteristics of the research are: - Access to the target population: our target population is represented by miners active and mobile in the south of the Guiana Shield, between Amapá (Brazil), French Guiana (France) and Suriname. To overcome the obstacles posed by the remoteness and clandestinity of the communities of interest, our intervention will take place in the logistical and support hubs (staging areas) of the miners, located in the border regions between the above territories. Thus, it will take advantage of their periodic mobility between these bases and the gold mining sites, and reach the target population where it can be easily accessed. - The intervention will be combined and will include a common core (malaria health education activity) and two modules that will be offered to participants. Each participant (meeting the inclusion criteria) will be able to choose between participating to one or both modules. - The common core of health education will focus on malaria: its causes, means of prevention, the main differences between P. falciparum and P. vivax disease, the importance of a complete treatment against any form of Plasmodium spp. - Module A of the intervention will be treatment targeting asymptomatic individuals at risk of carrying P. vivax. The aim of this module is to prevent relapses and reduce the number of human hosts able to transmitthe parasite. - Module B of the intervention will correspond to the provision, after appropriate training, of a Malakit self-test and self-treatment kit. The aim of this module is to provide access to quality diagnosis and treatment for episodes of symptoms consistent with malaria that occur in situations of extreme remoteness from health services. - The purpose of this study is to evaluate a strategy that, if appropriate, can be implemented by health authorities in countries with residual malaria transmission in populations with characteristics similar to our study population. The investigators will therefore use a pragmatic approach so that the conclusions drawn can be transposed as easily as possible to real life, while at the same time putting great effort into the safety of the intervention. Thus, the study field workers who will administer the intervention will have a similar profile to health workers recruited by a large number of malaria control programmes, particularly in remote areas. In addition, monitoring will be simplified and monitoring data can be collected both through face-to-face visits and remotely administered questionnaires. - The investigators chose to design many of the components of the intervention and study with a participatory approach. - In order to generate the data necessary for health authorities to potentially take ownership of the intervention in the future, the study will evaluate two aspects of the intervention: effectiveness and implementation. - First, the investigators want to evaluate the population-scale effectiveness of the intervention to reduce malaria transmission with a quasi-experimental approach. - Secondly, the investigators will analyse the implementation of the intervention, and generate valuable knowledge for further implementation within local health services. This evaluation will be carried out through the components of the CUREMA study: the intervention itself, pre/post-intervention cross-sectional surveys, the qualitative component and the modelling of epidemiological surveillance data. • The implementation of these components will have an expected duration of approximately 27 months, the start of inclusions is scheduled for September 2022.
The goal of this study is to evaluate the operational feasibility of using a new treatment algorithm for Malaria Vivax in Peru. The implementation package includes the following interventions: - A revised vivax treatment algorithm that incorporates new Radical Cure tools (G6PD test + Tafenoquine or Primaquine) - The training of Health Care Providers ( HCPs) in the revised algorithm and the use of the new RC tools - Patient counselling - A follow-up visit at Day 3 [+2 days] for patients after treatment start - Accompanying supporting measures: job aids, strengthening of supervision and PV processes
Although Plasmodium vivax (P. vivax), one of the five malaria species causing parasites, has the widest geographical distribution, it is rare in sub-Saharan Africa due to the absence of a red blood cell receptor (Duffy antigen) in black Africans. Duffy-negative individuals are, for the most part, therefore refractory to P. vivax infection and the Duffy-negative phenotype is found at highest frequencies in Africa, whereas it is relatively rare elsewhere. P. vivax has however, been observed as single infections in up to 5% of Duffy-negative febrile patients in one health facility in Dschang, a region of low malaria transmission in Western highlands of Cameroon. Whereas in the littoral South West and Southern forest of Cameroon characterised by high malaria transmission, areas, there are contrasting molecular evidence of human P. vivax infection. While important, the significance is limited from an epidemiological point of view, concerning the source, transmission, distribution range of P. vivax. There is thus a challenge in the true estimation of malaria burden, as well as the attributable parasite species in infections occurring in the low transmission areas of Western Cameroon. As a consequence, our understanding of the local epidemiology of malaria in Western Cameroon warrants formal investigation. The current proposal is a multi-centre observational study. Its purpose is to characterise the malaria species composition and particularly exposure and burden of P. vivax across malaria endemic settings in Cameroon. It will use multiplex serological methods based on quantitative suspension array on finger-stick blood samples collected from febrile patients of ages 1-100 during two malaria transmission seasons in different eco-climatic regions in Cameroon.
This study assesses the effectiveness of reactive focal mass drug administration (rfMDA), targeting both village and forest working populations, compared to control for reducing the health promotion hospital-level (sub-district) incidence and prevalence of P. falciparum and P. vivax within five provinces in Thailand.
The main determinant of primaquine efficacy is the total dose of primaquine administered, rather than the dosing schedule. Infants and children younger than 4 years of age are at a higher risk of frequent relapses than older age groups, which may lead to severe anaemia. In view of this issue, after Glucose-6-phosphate dehydrogenase (G6PD) testing, WHO recommends the use of a low dose (0·25 mg/kg of bodyweight) of primaquine for 14 days in infants aged 6 months and older, as a follow-up treatment for malaria caused by P. vivax and P. ovale. Nevertheless, previous trials have demonstrated that the standard low dose regimen of primaquine (3.5 mg/kg total) fails to prevent relapses in many different endemic locations. For this reason, the 2010 WHO antimalarial guidelines now recommend a high dose regimen of 7 mg/kg (equivalent to an adult dose of 30mg per day), although many countries still recommend lower doses for fear of causing more serious harm to unscreened G6PD deficiency patients. The pharmacokinetics of several antimalarial drugs are different in children younger than 10 years of age or who are underweight for their age compared with children of 10 years and older and adults.The doses of several antimalarials in children are suboptimal. This oversight is a consequence of designing dosing regimens in a different population (i.e., adults) for the one most affected by the disease and this has led to revisions of some dosing recommendations. The different pharmacokinetic performance of drugs in children might also relate to maturation (e.g., of metabolic processes, particularly in the first 2 years of life). Pharmacogenomic factors affecting drug metabolism are increasingly being studied. Polymorphisms in cytochrome P4502D6 are associated with different primaquine metabolizer phenotypes with resulting differing efficacies for radical cure. Shorter courses of higher daily doses of primaquine have the potential to improve adherence and, thus, effectiveness without compromising efficacy. If the efficacy, tolerability and safety of short-course, high-dose primaquine regimens can be assured across the range of endemic settings, along with reliable point-of-care G6PD deficiency diagnostics, then this would be a major advance in malaria treatment by improving adherence and thus the effectiveness of anti-relapse therapy.
The study will be an open-labelled randomized clinical trial to determine therapeutic efficacy. Note that this will not be an Investigational New Drug application, as only World Health Organization (WHO)-approved drugs will be used at dosage and for conditions approved.
This study assesses the effectiveness and feasibility of enhanced reactive case detection (RACD) targeting high-risk villages and forest workers for reducing Plasmodium falciparum and Plasmodium vivax transmission in southern Lao Peoples Democratic Republic. The authors hypothesize that enhanced community-based RACD will be more effective than standard of care case management and RACD at reducing P. falciparum and P. vivax confirmed case incidence and parasite prevalence over an 18-month period in Lao Peoples Democratic Republic.