17
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Atovaquone and proguanil hydrochloride compared with chloroquine or pyrimethamine/sulfadoxine for treatment of acute Plasmodium falciparum malaria in Peru

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          The efficacy and safety of a fixed-dose combination of atovaquone and proguanil hydrochloride (MalaroneTM) were compared with chloroquine or pyrimethamine/sulfadoxine in patients with acute falciparum malaria in northern Peru. Patients were initially randomized to receive 1,000 mg atovaquone and 400 mg proguanil hydrochloride daily for 3 days (n=15) or 1,500 mg chloroquine (base) over a 3 day period (n=14) (phase 1). The cure rate with chloroquine was lower than expected and patients were subsequently randomized to receive a single dose of 75 mg pyrimethamine and 1,500 mg sulfadoxine (n=9) or atovaquone/proguanil as before (n=5) (phase 2). In phase 1, atovaquone/proguanil was significantly more effective than chloroquine (cure rate 100% [14/14] versus 8% [1/13], P<0.0001). In phase 2, atovaquone/proguanil and pyrimethamine/sulfadoxine were both highly effective (cure rates 100% [5/5] and 100% [7/7]). There were no significant differences between treatment groups in parasite or fever clearance times. Adverse events were typical of malarial symptoms and did not differ significantly between groups. Overall efficacy of atovaquone/proguanil was 100% for treatment of acute falciparum malaria in a region with a high prevalence of chloroquine resistance.

          Related collections

          Most cited references24

          • Record: found
          • Abstract: found
          • Article: not found

          Site of action of the antimalarial hydroxynaphthoquinone, 2-[trans-4-(4'-chlorophenyl) cyclohexyl]-3-hydroxy-1,4-naphthoquinone (566C80).

          The site of action of the antimalarial compound 2-[trans-4-(4'-chlorophenyl) cyclohexyl]-3-hydroxy-1,4-naphthoquinone (566C80), would appear to be the mitochondrial respiratory chain. Studies reported herein have demonstrated 566C80 to be a potent and selective mitochondrial inhibitor with mitochondria isolated from Plasmodium falciparum and P. yoelii. Selective assay of individual respiratory chain complexes has shown the primary site of action of 566C80 to be the cytochrome bc1 complex (Complex III): supportive evidence from difference spectroscopy indicates the site of inhibition to lie between cytochromes b and c1 of this complex. Using [14C]566C80, evidence is presented which suggests that 566C80 may become irreversibly bound to a polypeptide with an approximate molecular mass of 11,500 Da.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Towards an understanding of the mechanism of pyrimethamine-sulfadoxine resistance in Plasmodium falciparum: genotyping of dihydrofolate reductase and dihydropteroate synthase of Kenyan parasites.

            The antifolate combination of pyrimethamine (PM) and sulfadoxine (SD) is the last affordable drug combination available for wide-scale treatment of falciparum malaria in Africa. Wherever this combination has been used, drug-resistant parasites have been selected rapidly. A study of PM-SD effectiveness carried out between 1997 and 1999 at Kilifi on the Kenyan coast has shown the emergence of RI and RII resistance to PM-SD (residual parasitemia 7 days after treatment) in 39 out of 240 (16.25%) patients. To understand the mechanism that underlies resistance to PM-SD, we have analyzed the dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) genotypes of 81 patients. Fifty-one samples were obtained, before treatment, from patients who remained parasite free for at least 7 days after treatment. For a further 20 patients, samples were obtained before treatment and again when they returned to the clinic with parasites 7 days after PM-SD treatment. Ten additional isolates were obtained from patients who were parasitemic 7 days after treatment but who were not sampled before treatment. More than 65% of the isolates (30 of 46) in the initial group had wild-type or double mutant DHFR alleles, and all but 7 of the 47 (85%) had wild-type DHPS alleles. In the paired (before and after treatment) samples, the predominant combinations of DHFR and DHPS alleles before treatment were of triple mutant DHFR and double mutant DHPS (41% [7 of 17]) and of double mutant DHFR and double mutant DHPS (29% [5 of 17]). All except one of the posttreatment isolates had triple mutations in DHFR, and most of these were "pure" triple mutants. In these isolates, the combination of a triple mutant DHFR and wild-type DHPS was detected in 6 of 29 cases (20.7%), the combination of a triple mutant DHFR and a single mutant (A437G) DHPS was detected in 4 of 29 cases (13.8%), and the combination of a triple mutant DHFR and a double mutant (A437G, L540E) DHPS was detected in 16 of 29 cases (55.2%). These results demonstrate that the triply mutated allele of DHFR with or without mutant DHPS alleles is associated with RI and RII resistance to PM-SD. The prevalence of the triple mutant DHFR-double mutant DHPS combination may be an operationally useful marker for predicting the effectiveness of PM-SD as a new malaria treatment.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Interactions of atovaquone with other antimalarial drugs against Plasmodium falciparum in vitro.

              A series of Plasmodium falciparum in vitro drug sensitivity studies were conducted in order to evaluate atovaquone in combination with other antimalarial drugs and thus to identify a potential partner for a fixed combination. The derived isobolograms indicated that drug interactions ranged from antagonism through addition to synergy. Of particular note were the quinolines and artemisinin analogues, which were all antagonistic, and the biguanides and tetracycline, which showed synergy. Proguanil emerged as the most promising of the current antimalarials as a partner for atovaquone in a fixed combination, with tetracycline as back-up.
                Bookmark

                Author and article information

                Journal
                bjid
                Brazilian Journal of Infectious Diseases
                Braz J Infect Dis
                Brazilian Society of Infectious Diseases (Salvador, BA, Brazil )
                1413-8670
                1678-4391
                April 2001
                : 5
                : 2
                : 67-72
                Affiliations
                [02] Talent OR orgnamePharmaceutical Systems Inc. USA
                [01] Lima orgnameUniversidad Peruana Cayetano Heredia orgdiv1Alexander von Humboldt Tropical Medicine Institute Peru
                [03] Greenford orgnameGlaxo Wellcome Research and Development UK
                Article
                S1413-86702001000200004 S1413-8670(01)00500204
                10.1590/S1413-86702001000200004
                ee0fd8fd-113b-4b1a-a826-dc5b274eb63e

                This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

                History
                : 21 April 2001
                : 15 January 2001
                Page count
                Figures: 0, Tables: 0, Equations: 0, References: 22, Pages: 6
                Product

                SciELO Brazil

                Categories
                Original Papers

                proguanil,Malarone,atovaquone,chloroquine resistance,Peru
                proguanil, Malarone, atovaquone, chloroquine resistance, Peru

                Comments

                Comment on this article

                scite_

                Similar content769

                Cited by3

                Most referenced authors218