Kasia StepniewskaWalter R.J. TaylorMayfong MayxayRic PriceFrank SmithuisJean Paul GuthmannKaren BarnesHla Yin MyintMartin AdjuikPiero OlliaroSasithon PukrittayakameeSornchai LooareesuwanTran Tinh HienJeremy FarrarFrançois NostenNicholas P.J. DayNicholas J. WhiteMahidol UniversityShoklo Malaria Research UnitOrganisation Mondiale de la SanteWellcome Trust-Mahosot Hospital-Oxford Tropical Medicine Research CollaborationMedecins sans Frontieres-HollandEpicentreUniversity of Cape TownOxford University Clinical Research UnitUCLChurchill Hospital2018-07-242018-07-242004-11-01Antimicrobial Agents and Chemotherapy. Vol.48, No.11 (2004), 4271-4280006648042-s2.0-7244219957https://repository.li.mahidol.ac.th/handle/20.500.14594/21508To determine the optimum duration of follow-up for the assessment of drug efficacy against Plasmodium falciparum malaria, 96 trial arms from randomized controlled trials (RCTs) with follow-up of 28 days or longer that were conducted between 1990 and 2003 were analyzed. These trials enrolled 13,772 patients, and participating patients comprised 23% of all patients enrolled in RCTs over the past 40 years; 61 (64%) trial arms were conducted in areas where the rate of malaria transmission was low, and 58 (50%) trial arms were supported by parasite genotyping to distinguish true recrudescences from reinfections. The median overall failure rate reported was 10% (range, 0 to 47%). The widely used day 14 assessment had a sensitivity of between O and 37% in identifying treatment failures and had no predictive value. Assessment at day 28 had a sensitivity of 66% overall (28 to 100% in individual trials) but could be used to predict the true failure rate if either parasite genotyping was performed (r2= 0.94) or if the entomological inoculation rate was known. In the assessment of drug efficacy against falciparum malaria, 28 days should be the minimum period of follow-up.Mahidol UniversityMedicinePharmacology, Toxicology and PharmaceuticsArticleSCOPUS10.1128/AAC.48.11.4271-4280.2004