title: In vivo efficacy of mefloquine for the treatment of Falciparum malaria in Brazil.
abstract: Ninety-four patients with falciparum malaria were treated with mefloquine (1000-mg single dose) and remained hospitalized in a malaria-free area for a minimum of 28 days. There was 1 parasitologic failure (grade I resistance [RI]) for a 99% cure rate (95% confidence interval, 94.2%-99.7%). Mean parasite clearance time by thick smear was 45.7 h (SD, 11.4 h). The subject in whom therapy failed had a parasite clearance time (71 h) >2 SD above the population mean. His plasma mefloquine level 48 h after administration was lower (578 ng/mL) than the range of levels from 8 randomly selected cured subjects (834-2360 ng/mL). The IC50 to mefloquine for the recrudescent strain of the RI failure was in the upper 90th percentile of IC50 values from 30 cured subjects. These results show a high mefloquine cure rate but document the onset and mechanism of the emergence of resistance.
authors.affiliation: Infectious and Parasitic Diseases Department, University of São Paulo, São Paulo, Brazil.
authors.forename: C
authors.initials: C
authors.lastname: Cerutti
authors.forename: R R
authors.initials: RR
authors.lastname: Durlacher
authors.forename: F E
authors.initials: FE
authors.lastname: de Alencar
authors.forename: A A
authors.initials: AA
authors.lastname: Segurado
authors.forename: L W
authors.initials: LW
authors.lastname: Pang
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000962:Antimalarials / Q000494:pharmacology / Q000627:therapeutic use*; D001938:Brazil; D004351:Drug Resistance; D006801:Humans; D016778:Malaria, Falciparum / Q000188:drug therapy*; D008297:Male; D015767:Mefloquine / Q000494:pharmacology / Q000627:therapeutic use*; D008875:Middle Aged; D010963:Plasmodium falciparum / Q000187:drug effects; D016896:Treatment Outcome
chemical_list: D000962:Antimalarials; D015767:Mefloquine