title: In vitro sensitivity of antimalarial drugs and correlation with clinico-parasitological response following treatment with a 3-day artesunate-mefloquine combination in patients with falciparum malaria along the Thai-Myanmar border.
abstract: A 3-day artesunate-mefloquine combination therapy has been using as first-line treatment for acute uncomplicated Plasmodium falciparum malaria in Thailand since 1995 on the background of mefloquine resistance. The aim of the present study was to assess sensitivity of P. falciparum isolates (n=44) in an area along the Thai-Myanmar border (year 2009) to artesunate, mefloquine, chloroquine and quinine, including their correlation with clinico-parasitological response. Twenty, 19, and 5 isolates were collected from patients with 'Adequate Clinical and Parasitological Response (ACPR)', 'Late Parasitological Failure (LPF)' and 're-infection', respectively. The IC50of artesunate and mefloquine were significantly higher in patients with LPF compared with ACPR and re-infection. The proportion of isolates with declined artesunate or mefloquine sensitivity in the LPF group (47.4%) was significantly higher than the ACPR group (5.0%). A weak but statistical significant correlation (r=0.384, p=0.01) was observed between IC50values of artesunate and parasite clearance time (PCT). There was no significant relationship between in vitro sensitivity of parasite isolates to chloroquine or quinine and clinical response. In vitro susceptibility of P. falciparum isolates to artesunate and mefloquine may be used as a useful reliable tool to predict clinico-pathological response following a 3-day artesunate-mefloquine combination therapy.
authors.affiliation: Drug Discovery and Development Center, Thammasat University, Pathumthani 12121, Thailand.
authors.forename: Phunuch
authors.initials: P
authors.lastname: Muhamad
authors.affiliation: Drug Discovery and Development Center, Thammasat University, Pathumthani 12121, Thailand.
authors.forename: Artitaya
authors.initials: A
authors.lastname: Thiengsusuk
authors.affiliation: Center of Excellence in Pharmacology and Molecular Biology of Malaria and Cholangiocarcinoma, Chulabhorn International College of Medicine, Thammasat University, Pathumthani 12121, Thailand.
authors.forename: Papichaya
authors.initials: P
authors.lastname: Phompradit
authors.affiliation: Center of Excellence in Pharmacology and Molecular Biology of Malaria and Cholangiocarcinoma, Chulabhorn International College of Medicine, Thammasat University, Pathumthani 12121, Thailand. Electronic address: kesaratmu@yahoo.com.
authors.forename: Kesara
authors.initials: K
authors.lastname: Na-Bangchang
mesh_terms: D000293:Adolescent; D000328:Adult; D000962:Antimalarials / Q000494:pharmacology*; D037621:Artemisinins / Q000494:pharmacology*; D000077332:Artesunate; D002738:Chloroquine / Q000494:pharmacology; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D016778:Malaria, Falciparum / Q000188:drug therapy* / Q000469:parasitology; D008297:Male; D015767:Mefloquine / Q000494:pharmacology*; D008875:Middle Aged; D002052:Myanmar; D021261:Parasitic Sensitivity Tests; D010963:Plasmodium falciparum / Q000187:drug effects* / Q000302:isolation & purification; D011803:Quinine / Q000494:pharmacology; D013785:Thailand; D055815:Young Adult
chemical_list: D000962:Antimalarials; D037621:Artemisinins; D000077332:Artesunate; D002738:Chloroquine; D011803:Quinine; D015767:Mefloquine
keywords: Antimalrial drug resistance; Artemisinin combination therapy; Plasmodium falciparum; Treatment response; in vitro sensitivity test