Compliance with a three-day course of artesunate-mefloquine combination and baseline anti-malarial treatment in an area of Thailand with highly multidrug resistant falciparum malaria

<p>Abstract</p> <p>Background</p> <p>Artemisinin-based combination therapy (ACT) is presently recommended by the World Health Organization as first-line treatment for uncomplicated <it>Plasmodium falciparum </it>malaria in several countries, as a mean of prolonging the effectiveness of first-line malaria treatment regimens. A three-day course of artesunate-mefloquine (4 mg/kg body weight once daily for three consecutive days, plus 15 and 10 mg/kg body weight mefloquine on the first and second days) has been adopted by Malaria Control Programme of Thailand as first-line treatment for uncomplicated falciparum malaria all over the country since 2008. The gametocytocydal anti-malarial drug primaquine is administered at the dose of 30 mg (0.6 mg/kg) on the last day. The aim of the present study was to assess patient compliance of this combination regimen when applied to field condition.</p> <p>Methods</p> <p>A total of 240 patients (196 males and 44 females) who were attending the malaria clinics in Mae-Sot, Tak Province and presenting with symptomatic acute uncomplicated falciparum malaria, with no reappearance of <it>Plasmodium vivax </it>parasitaemia during follow-up were included into the study. The first dose of the treatment was given to the patients under direct supervision. All patients were given the medication for self-treatment at home and were requested to come back for follow-up on day 3 of the initial treatment. Baseline (day 0) and day 3 whole blood mefloquine and plasma primaquine concentrations were determined by high performance liquid chromatography.</p> <p>Results</p> <p>Two patients had recrudescence on days 28 and 35. The Kaplan-Meier estimate of the 42-day efficacy rate of this combination regimen was 99.2% (238/240). Based on whole blood mefloquine and plasma primaquine concentrations on day 3 of the initial treatment, compliance with mefloquine and primaquine in this three-day artesunate-mefloquine combination regimen were 96.3% (207/215), and 98.5% (197/200), respectively. Baseline mefloquine and primaquine levels were observed in 24 and 16% of the patients.</p> <p>Conclusion</p> <p>The current first-line treatment and a three-day combination regimen of artesunate-mefloquine provides excellent patient compliance with good efficacy and tolerability in the treatment of highly multidrug resistance falciparum malaria. Previous treatment with mefloquine and primaquine were common in this area.</p

In vivo sensitivity monitoring of chloroquine for the treatment of uncomplicated vivax malaria in four bordered provinces of Thailand during 2009–2010

Background & objectives: Chloroquine (CQ), followed by 14-day primaquine, is the recommended regimen forthe treatment of Plasmodium vivax infection in Thailand. CQ resistant P. vivax (CRPv) has not yet challengedthe efficacy of the drug. The present study was conducted to assess the current response of P. vivax to CQ alonein Thailand.Methods: A 28-day in vivo therapeutic efficacy study was conducted from June 2009 to December 2010 in 4sentinel sites. Recurrence of parasitaemia and the clinical condition of patients were assessed on each visitduring follow-up. The drug levels in recurrent patients’ blood were measured using HPLC. Data were analyzedusing the WHO 2008 program for the analysis of in vivo tests.Results: Of the total 212 patients included in the study, 201 completed the 28-days follow-up, while 11 wereexcluded. In five patients (2.5%), parasitaemia reappeared within the 28-days follow-up. On the day of recurrentparasitaemia, the level of chloroquine/desethylchloroquine (CQ-DCQ) was above the minimum effectiveconcentration (>100 ng/ml) in one patient, but lower in four patients.Conclusion: Reappearance of the parasite within 28 days of follow-up in one of five patients was due to parasiteresistance to CQ. The 2.5% prevalence of CQ treatment failure for P. vivax malaria in the study areas signals theneed to launch monitoring activities for CQ resistant P. vivax in malaria endemic areas in order to detect furtherdevelopment of parasite resistance and to estimate the level of burden across the countr

G6PD testing in support of treatment and elimination of malaria: recommendations for evaluation of G6PD tests

Malaria elimination will be possible only with serious attempts to address asymptomatic infection and chronic infection by both Plasmodium falciparum and Plasmodium vivax. Currently available drugs that can completely clear a human of P. vivax (known as “radical cure”), and that can reduce transmission of malaria parasites, are those in the 8-aminoquinoline drug family, such as primaquine. Unfortunately, people with glucose-6-phosphate dehydrogenase (G6PD) deficiency risk having severe adverse reactions if exposed to these drugs at certain doses. G6PD deficiency is the most common human enzyme defect, affecting approximately 400 million people worldwide. Scaling up radical cure regimens will require testing for G6PD deficiency, at two levels: 1) the individual level to ensure safe case management, and 2) the population level to understand the risk in the local population to guide Plasmodium vivax treatment policy. Several technical and operational knowledge gaps must be addressed to expand access to G6PD deficiency testing and to ensure that a patient’s G6PD status is known before deciding to administer an 8-aminoquinoline-based drug. In this report from a stakeholder meeting held in Thailand on October 4 and 5, 2012, G6PD testing in support of radical cure is discussed in detail. The focus is on challenges to the development and evaluation of G6PD diagnostic tests, and on challenges related to the operational aspects of implementing G6PD testing in support of radical cure. The report also describes recommendations for evaluation of diagnostic tests for G6PD deficiency in support of radical cure

In vivo sensitivity monitoring of chloroquine for the treatment of uncomplicated vivax malaria in four bordered provinces of Thailand during 2009–2010

ABSTRACT Background &amp; objectives: Chloroquine (CQ), followed by 14-day primaquine, is the recommended regimen for the treatment of Plasmodium vivax infection in Thailand. CQ resistant P. vivax (CRPv) has not yet challenged the efficacy of the drug. The present study was conducted to assess the current response of P. vivax to CQ alone in Thailand. Methods: A 28-day in vivo therapeutic efficacy study was conducted from June 2009 to December 2010 in 4 sentinel sites. Recurrence of parasitaemia and the clinical condition of patients were assessed on each visit during follow-up. The drug levels in recurrent patients&apos; blood were measured using HPLC. Data were analyzed using the WHO 2008 program for the analysis of in vivo tests. Results: Of the total 212 patients included in the study, 201 completed the 28-days follow-up, while 11 were excluded. In five patients (2.5%), parasitaemia reappeared within the 28-days follow-up. On the day of recurrent parasitaemia, the level of chloroquine/desethylchloroquine (CQ-DCQ) was above the minimum effective concentration (&gt;100 ng/ml) in one patient, but lower in four patients. Conclusion: Reappearance of the parasite within 28 days of follow-up in one of five patients was due to parasite resistance to CQ. The 2.5% prevalence of CQ treatment failure for P. vivax malaria in the study areas signals the need to launch monitoring activities for CQ resistant P. vivax in malaria endemic areas in order to detect further development of parasite resistance and to estimate the level of burden across the country