{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,14]],"date-time":"2025-12-14T16:10:50Z","timestamp":1765728650312},"reference-count":49,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2018,1,10]]},"abstract":"<jats:p>Pyronaridine, a Mannich base antimalarial agent with a high activity against chloroquine-resistant <jats:italic>Plasmodium falciparum<\/jats:italic>, has been combined with artesunate as a new artemisinin based combination therapy (ACT). Pyronaridine\u2013artesunate combination could be one of the choices for the treatment of uncomplicated falciparum malaria in multidrug-resistant areas including Thailand. The aim of this study was to determine in vitro sensitivity and cross-resistance pattern of pyronaridine in Thai isolates of <jats:italic>P. falciparum<\/jats:italic>. In addition, the influence of resistant genes concerning in vitro pyronaridine sensitivity was determined. The mean pyronaridine 50% inhibitory concentration (IC<jats:sub>50<\/jats:sub>) of 118 parasite isolates was 5.6 \u00b1 3.1 nM (range = 0.2\u201315.4 nM) with a significant positive correlation with artesunate IC<jats:sub>50<\/jats:sub> (<jats:italic>r<\/jats:italic> = 0.246, <jats:italic>P<\/jats:italic> = 0.008) and amodiaquine IC<jats:sub>50<\/jats:sub> (<jats:italic>r<\/jats:italic> = 0.220, <jats:italic>P<\/jats:italic> = 0.042) and a significant negative correlation with quinine IC<jats:sub>50<\/jats:sub> (<jats:italic>r<\/jats:italic> = <jats:italic>\u2212<\/jats:italic>0.185, <jats:italic>P<\/jats:italic> = 0.047). Parasites containing the <jats:italic>pfmdr1<\/jats:italic> 86Y allele exhibited significantly reduced pyronaridine sensitivity compared with those with the <jats:italic>pfmdr1<\/jats:italic> N86 allele (7.6 \u00b1 3.3 nM and 5.4 \u00b1 3.0 nM, respectively, <jats:italic>P<\/jats:italic> = 0.032, independent <jats:italic>t<\/jats:italic> test); however, the difference may not be clinically relevant. Pyronaridine\u2013artesunate could be the candidate ACT to treat multidrug-resistant falciparum malaria in Thailand with careful monitoring.<\/jats:p>","DOI":"10.4269\/ajtmh.17-0286","type":"journal-article","created":{"date-parts":[[2017,10,24]],"date-time":"2017-10-24T07:00:36Z","timestamp":1508828436000},"page":"51-56","source":"Crossref","is-referenced-by-count":5,"title":["In Vitro Sensitivity of Pyronaridine in Thai Isolates of Plasmodium falciparum"],"prefix":"10.4269","volume":"98","author":[{"given":"Kittiya","family":"Mahotorn","sequence":"first","affiliation":[{"name":"Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peerapan","family":"Tan-ariya","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thunyapit","family":"Thita","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Toon","family":"Ruang-areerate","sequence":"additional","affiliation":[{"name":"Department of Parasitology, Phramongkutklao College of Medicine, Bangkok 10400, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Naruemon","family":"Sittichot","sequence":"additional","affiliation":[{"name":"Department of Parasitology, Phramongkutklao College of Medicine, Bangkok 10400, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nantana","family":"Suwandittakul","sequence":"additional","affiliation":[{"name":"Department of Parasitology, Phramongkutklao College of Medicine, Bangkok 10400, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mathirut","family":"Mungthin","sequence":"additional","affiliation":[{"name":"Department of Parasitology, Phramongkutklao College of Medicine, Bangkok 10400, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"2795","reference":[{"year":"2012","author":"World Health Organization","key":"b1"},{"key":"b2","series-title":"Proc Natl Acad Sci USA","first-page":"240","article-title":"Genetic loci associated with delayed clearance of Plasmodium falciparum following artemisinin treatment in southeast Asia","volume":"110","author":"Takala-Harrison","year":"2013"},{"key":"b3","series-title":"N Engl J Med","first-page":"455","article-title":"Artemisinin resistance in Plasmodium falciparum malaria","volume":"361","author":"Dondorp","year":"2009"},{"key":"b4","series-title":"N Engl J Med","first-page":"411","article-title":"Spread of artemisinin resistance in Plasmodium falciparum 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