Active clinical trials for "Malaria, Vivax"

The purpose of this study is to determine the efficacy of pyrimethamine/sulfdoxine (Fansidar®) for the treatment of uncomplicated falciparum malaria in the Peruvian Amazon. Reports in the mid 1990s indicated that Fansidar was failing to cure patients with confirmed falciparum malaria. The study design was based on accepted WHO parasitological and clinical outcomes to determine the overall efficacy of Fansider and inform the Peruvian National Malaria Control authorities as to the continued wisdom of recommending Fansidar as first line treatment for uncomplicated falciparum malaria in the Peruvian Amazon.

Multidrug resistant strains of P.falciparum and P.vivax are becoming increasingly prevalent in the Asia Pacific rim. To determine the efficacy of locally recommended antimalarial protocols in Papua, Indonesia, consecutive patients presenting to a rural clinic were enrolled into a prospective efficacy study. Patients with uncomplicated falciparum malaria were treated with chloroquine plus sulfadoxine-pyrimethamine and those with vivax malaria with chloroquine monotherapy. Patients failing therapy received unsupervised oral quinine +/- doxycycline for 7 days. Follow-up was continued for 42 days for falciparum malaria and 28 days for vivax malaria. The study hypothesis was that current recommended antimalarial protocols were no longer effective.

The primary aim of the comparative trial is to assess the relative safety and efficacy of two artemisinin containing regimens: amodiaquine plus artesunate (AAQ) and artekin both administered once daily for 3 days.

The main determinant of primaquine efficacy is the total dose of primaquine administered, rather than the dosing schedule. 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 G6PDd patients. Shorter courses of higher daily doses of primaquine have the potential to improve adherence and thus effectiveness without compromising efficacy. Primaquine also has relatively weak but clinically relevant asexual stage activity against P. vivax so larger daily doses may substantially augment chloroquine's blood stage activity at low levels of resistance. In Thailand directly observed primaquine (1mg/kg/day) administered over 7 days was well tolerated and reduced relapses by day 28 to 4%. This is encouraging but not definitive since many relapses present after one month. Longer follow-up is needed to distinguish whether relapse was prevented or deferred. 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 G6PDd diagnostics, then this new primaquine regimen would be a major advance in malaria treatment improving adherence to and thus the effectiveness of anti-relapse therapy. Due to the long duration of standard primaquine treatment regimens, courses are difficult to supervise, are poorly adhered to and lack effectiveness. This proposed multicentre randomised clinical trial will provide evidence across a variety of endemic settings on the safety and efficacy of high dose-short course primaquine in G6PD normal patients. In a parallel single arm study the investigators will also gather safety data on the use of weekly primaquine in patients with G6PDd. This study aims to generate evidence that will directly inform global public health policy for the radical cure of P. vivax. A better understanding of the risks and benefits of primaquine is crucial in persuading policy makers and clinicians of the importance of the radical cure of vivax malaria that will reduce the parasite reservoir and decrease transmission. The funder is Medical Research Council, UK. Grant number: MRC Reference: MR/K007424/1

This is a randomized open-label trial to evaluate the efficacy of chloroquine (CQ) alone compared to chloroquine+primaquine (CQ+PQ) in the treatment of uncomplicated malaria caused by Plasmodium vivax infection in a endemic area in the westernmost part of the Amazon Basin of Brazil. The duration of follow up for evaluating CQ efficacy as a schizonticidal drug was 28 days. The duration of complete follow up to detect recurrent P. vivax infections by passive surveillance was six months. All patients in the CQ alone arm received 7 days of PQ treatment (3.5mg/kg total dose) starting on day 28 of the study follow-up.

We plan to assess the efficacy of 3 different regimens of chloroquine and primaquine for the treatment of P. vivax infections in Cruzeiro do Sul, Acre, Brazil. Patients will be divided in 3 different groups: treatment with regular dose of primaquine (0.5 mg/kg per day for 7 days) with directly observed therapy; regular dose of primaquine without directly observed therapy; and increased total dose of primaquine (0.5 mg/kg per day for14 days) with directly observed therapy. All patients will receive chloroquine (CQ) for three days at a daily dose of approximately 25 mg/Kg in accordance with the Brazilian National Malaria Control guidelines. Clinical and parasitologic parameters will be monitored over a 28-day follow-up period to evaluate drug efficacy and for a total period of 168 days (24 weeks) to evaluate chances of recrudescence, relapse, or reinfection. Results from this drug efficacy study will be used to assist the Brazilian Ministry of Health in assessing their national malaria treatment policy for P. vivax malaria.

This Phase 2a trial recruits adult patients with uncomplicated P. vivax or P. falciparum blood-stage malaria mono-infection. The study drug SJ733 will be administered to examine its antimalarial efficacy, safety, and tolerability. This study also evaluates whether or not a fixed dose of the pharmacoenhancer cobicistat when given in combination with SJ733 significantly improves drug efficacy.

A Phase IIa Exploratory, Open label, Single Dose Regimen, Multiple Dose Testing Clinical Study to Assess the Preliminary Efficacy, Tolerability and Pharmacokinetics of OZ439 in adult patients with acute, uncomplicated Plasmodium falciparum or vivax malaria mono-infection.

This is an open label two-arm randomized prospective study of two treatments for P. vivax malaria. Patients meeting study inclusion criteria will be enrolled and allocated either chloroquine alone or chloroquine plus primaquine (0.25mg/kg/day for 14 days). Patients will be followed-up for 1 year, with clinical and laboratory examinations at each visit. Patients with recurrent P. vivax infection will be treated with the same medication as initially randomized unless contraindicated. Recurrences in the two arms will be compared to estimate the risk of and mean duration to relapse, classify the relapse pattern as early or late relapse and to estimate the efficacy and safety of the study drugs. Polymerase Chain Reaction (PCR) analysis will be used as far as possible help to distinguish between relapse and re-infection. Samples for chloroquine pharmacokinetic analysis will be collected on day 7 from each study subject as well as on the day of recurrence if within 8 weeks of chloroquine

The purpose of this study is to compare the efficacy and safety of the fixed combination of pyronaridine artesunate (Pyramax®, PA) (180:60 mg) with that of standard chloroquine therapy in children and adults with acute, uncomplicated Plasmodium vivax malaria.