BackgroundIn malaria-endemic countries, large proportions of infected individuals are asymptomatic, constituting a reservoir of parasites for infection of newly hatched mosquitoes. This study evaluated the impact of screening and treatment of asymptomatic carriers of Plasmodium falciparum.MethodsEighteen villages were randomized (1:1) to study arms and inhabitants participated in four community screening campaigns: three before the rainy season ~1 month apart, and the fourth after the rains at ~12 months. On day 1 of campaigns 1–3, asymptomatic carriers in the intervention arm were identified by rapid diagnostic test and treated with artemether-lumefantrine. Outcomes were symptomatic malaria with parasite density >5,000/μL per person-year in children < 5 years and change in haemoglobin between days 1 and 28 of campaign 1.ResultsAt 12 months, the number of symptomatic malaria episodes with a parasite density >5,000/μL per person-year in children < 5 years was not significantly different between arms (1.69 vs 1.60, p = 0.3482). Mean haemoglobin change in asymptomatic carriers during campaign 1 was greater in the intervention vs control arm (+0.53 g/dL vs -0.21 g/dL, p < 0.0001). ANCOVA demonstrated that mean asymptomatic carriage at the cluster level was lower in the intervention vs control arm at day 1 of campaigns 2 (5.0% vs 34.9%, p < 0.0001) and 3 (3.5% vs 31.5%, p < 0.0001), but showed only a small difference at day 1 of campaign 4 (34.6% vs 37.6%, p = 0.2982). Mean gametocyte carriage was lower in the intervention vs control arm at day 1 of campaigns 2 and 3 (0.7% vs 5.4%, p < 0.0001; 0.5% vs 5.8%, p < 0.0001), but was similar at day 1 of campaign 4 (4.9% vs 5.1%, p = 0.7208).ConclusionsSystematic screening and treatment of asymptomatic carriers at the community level did not reduce clinical malaria incidence in the subsequent transmission season, indicating greater levels of parasite clearance are required to achieve a sustained impact in this setting.

BackgroundThe fixed dose combination of artemether-lumefantrine (AL) is the most widely used treatment for uncomplicated Plasmodium falciparum malaria. Relatively lower cure rates and lumefantrine levels have been reported in young children and in pregnant women during their second and third trimester. The aim of this study was to investigate the pharmacokinetic and pharmacodynamic properties of lumefantrine and the pharmacokinetic properties of its metabolite, desbutyl-lumefantrine, in order to inform optimal dosing regimens in all patient populations.Methods and findingsA search in PubMed, Embase, ClinicalTrials.gov, Google Scholar, conference proceedings, and the WorldWide Antimalarial Resistance Network (WWARN) pharmacology database identified 31 relevant clinical studies published between 1 January 1990 and 31 December 2012, with 4,546 patients in whom lumefantrine concentrations were measured. Under the auspices of WWARN, relevant individual concentration-time data, clinical covariates, and outcome data from 4,122 patients were made available and pooled for the meta-analysis. The developed lumefantrine population pharmacokinetic model was used for dose optimisation through in silico simulations. Venous plasma lumefantrine concentrations 7 days after starting standard AL treatment were 24.2% and 13.4% lower in children weighing <15 kg and 15–25 kg, respectively, and 20.2% lower in pregnant women compared with non-pregnant adults. Lumefantrine exposure decreased with increasing pre-treatment parasitaemia, and the dose limitation on absorption of lumefantrine was substantial. Simulations using the lumefantrine pharmacokinetic model suggest that, in young children and pregnant women beyond the first trimester, lengthening the dose regimen (twice daily for 5 days) and, to a lesser extent, intensifying the frequency of dosing (3 times daily for 3 days) would be more efficacious than using higher individual doses in the current standard treatment regimen (twice daily for 3 days). The model was developed using venous plasma data from patients receiving intact tablets with fat, and evaluations of alternative dosing regimens were consequently only representative for venous plasma after administration of intact tablets with fat. The absence of artemether-dihydroartemisinin data limited the prediction of parasite killing rates and recrudescent infections. Thus, the suggested optimised dosing schedule was based on the pharmacokinetic endpoint of lumefantrine plasma exposure at day 7.ConclusionsOur findings suggest that revised AL dosing regimens for young children and pregnant women would improve drug exposure but would require longer or more complex schedules. These dosing regimens should be evaluated in prospective clinical studies to determine whether they would improve cure rates, demonstrate adequate safety, and thereby prolong the useful therapeutic life of this valuable antimalarial treatment.

Background. Orally administered antiviral therapy for genital herpes improves the time to lesion healing and resolves symptoms during an outbreak. Although traditional therapy for a recurrent episode for healthy adults has consisted of twice-daily dosing for 5 days, recent studies have indicated that shorter courses of antiviral therapy are effective. This study was conducted to assess the efficacy and safety of a patient-initiated, single-day regimen of famciclovir therapy, compared with placebo, in immunocompetent adult patients with recurrent genital herpes.Methods. This multicenter, multinational, randomized, double-blind, parallel-group, placebo-controlled study compared single-day, patient-initiated oral famciclovir (1000 mg given twice daily) with placebo for the treatment of recurrent genital herpes. Patients were instructed to initiate therapy within 6 h after onset of prodromal symptoms or genital herpes lesions.Results. Famciclovir reduced ( ) the time to healing of nonaborted lesions (i.e., those that did not P ! .001 progress beyond the papule stage) (median time, 4.3 vs. 6.1 days) and all nonaborted and aborted lesions (median time, 3.5 vs. 5.0 days), compared with placebo. The proportion of patients with aborted lesions was larger in the famciclovir group than in the placebo group (23.3% vs. 12.7%;). Adverse events in the famciclovir group P p .003 were infrequent overall; most were of mild-to-moderate severity and were similar to adverse events in the placebo group.Conclusions. A single-day regimen of patient-initiated famciclovir treatment was well tolerated and safe, and the healing of recurrent genital herpes lesions occurred ∼2 days faster than with placebo. Moreover, single-day famciclovir treatment stopped the development or progression of lesions beyond the papule stage. This convenient single-day regimen has the potential for improving patient compliance and satisfaction with therapy.