Zusammenfassung
Nach Eintritt der Mefloquinresistenz von Plasmodium falciparum in Thailand in den neunziger Jahren stellte sich die Kombinationstherapie mit Mefloquin und Artesunat in der Behandlung und Heilung von Patienten als effektiv heraus. Klinisch-parasitologisches Ansprechen und die in-vitro Sensibilität von P. falciparum wurden regelmäßig untersucht um etwaiges Versagen dieser Kombinationstherapie frühzeitig festzustellen. Frühere Studien zeigten, dass die in-vitro Aktivität von Artemisinin durch Retinol verstärkt werden kann. Gleiches konnte bei Mefloquine beobachtet werden. Nach weiterer Sensibilitätsminderung gegenüber Artemisinin und Mefloquin ergab sich die Frage, ob der Synergismus zwischen diesen Substanzen sowie Retinol in Mitleidenschaft gezogen wurde. Dies war Gegenstand der Studie. Erfolgreiche parallele Tests mit Mefloquine, Artemisinin, Retinol, Mefloquine-Artemisinin 5:1, wie auch mit Mefloquine-Artemisinin (5:1) + Retinol low, medium and high ergaben sich bei 43 von 48 ursprünglich angesetzten frischen Patientenisolaten. Die Retinol-Konzentrationen in den low, medium and high Konzentrationen entsprechen der fünfzigsten, fünfundsechzigsten und achtzigsten Percentile der physiologischen mittleren Konzentration von Retinol im Blut eines gesunden Erwachsenen. Die IC50, IC90 und IC99 Werte für Mefloquin zeigten einen Anstieg im Vergleich zu den Werten von 2008. In den Kombinationen mit Artemisinin und Retinol wurde mäßiger Synergismus bei der IC-50 beobachtet. Ausgeprägter Synergismus zeigte sich bei der IC-90 und IC-99.
Summary
Following the advent of mefloquine resistance in Plasmodium falciparum in Thailand in the 1990s, the combined treatment of falciparum malaria with artesunate and mefloquine was found to be highly effective in treating and curing the patients in the affected areas. Monitoring of the clinical-parasitological response and of the in vitro sensitivity of P. falciparum was systematically conducted in order to detect any signs of failure of this type of artemisinin-based combination treatment (ACT). In earlier observations the in vitro activity of artemisinin was found to be significantly enhanced when combined with retinol. The same applies to mefloquine. In order to check whether the synergism between artemisinin and mefloquine was maintained in the presence of retinol, the pharmacodynamic interaction of the three compounds was investigated in the western border area of Thailand. Successful parallel tests with mefloquine, artemisinin, retinol, mefloquine-artemisinin 5:1 as well as mefloquine-artemisinin (5:1) + retinol low, medium and high were obtained with 43 fresh parasite isolates. The retinol concentrations in the low, medium and high formulations corresponded to the 50th, 65th and 80th percentile of the physiological mean concentrations in the blood of healthy adults. The IC50, IC90 and IC99 values for mefloquine alone showed a further increase over the data of 2008. In the combinations with artemisinin and retinol moderate synergism was observed at the IC50, but synergism increased strongly at the IC90 and the IC99.
References
Shanks GD (1994) The rise and fall of mefloquine as an antimalarial drug in South East Asia. Mil Med 159: 275–81
Wongsrichanalai C, Sirichaisinthop J, Karwacki J, Congpuong K, Miller RS, Pang L, et al (2001) Drug resistant malaria on the Thai-Myanmar and Thai-Cambodian borders. Southeast Asian J Trop Med Public Health 32: 41–9
Wernsdorfer WH (1994) Epidemiology of drug resistance in malaria. Acta Trop 56: 143–56
Dondorp AM, Yeung S, White L, Nguon C, Day NP, Socheat D, et al (2010) Artemisinin resistance: current status and scenarios for containment. Nat Rev Microbiol; http://www.ncbi.nlm.nih.gov/pubmed/20208550
Hamzah J, Davis TM, Skinner-Adams TS, Beilby J (2004) Characterization of the effect of retinol on Plasmodium falciparum in vitro. Exp Parasitol 107: 136–44
Thurnham DI, Singkamani R (1991) The acute phase response and vitamin A status in malaria. Trans R Soc Trop Med Hyg 85: 194–9
Hautvast JL, Tolboom JJ, West EC, Kafwembe EM, Sauerwein RM, van Steveren WA (1998) Malaria is associated with reduced serum retinol levels in rural Zambian children. Int J Vitam Nutr Res 68: 384–8
Varandas I, Julien M, Gomes A, Rodrigues P, van Lerberghe W, Malveiro F, et al (2001) A randomised, double-blid, placebo-controlled clinical trial of vitamin A in severe malaria in hospitalised Mozambican children. Ann Trop Paediatr 21: 211–22
Thriemer K, Wernsdorfer G, Rojanawatsirivet C, Kollaritsch H, Sirichainsinthop J, Wernsdorfer WH (2005) In vitro activity of artemisinin alone and in combination with retinol against Plasmodium falciparum. Wien Klin Wochenschr 117[Suppl 4]: 45–8
Gruber M, Wernsdorfer G, Satimai W, Wiedermann U, Congpuong K, Wernsdorfer WH (2009) Pharmacodynamic interaction between mefloquine and retinol in Plasmodium falciparum in vitro. Wien Klin Wochenschr 121[Suppl 3]: 27–31
World Health Organisation (1990) In vitro micro-test (Mark II) for the assesement of the response of Plasmodium falciparum to chloroquine, mefloquine, quinine, sulfadoxine/pyrimethamine and amodiaquine. WHO Document MAP/87.2, Revision 1, June 1990. WHO, Geneva
World Health Organisation (1991) Basic malaria microscopy. Part I. WHO, Geneva
Litchfield JT Jr, Wilcoxon F (1949) A simplified method of evaluating dose-effect experiments. J Pharm Exp Ther 96: 99–113
Wernsdorfer WH, Wernsdorfer MG (1995) The evaluation of in vitro tests for the assessment of drug response in Plasmodium falciparum. Mitteilungen der Österreichischen Gesellschaft für Tropenmedizin und Parasitologie 17: 221–8
Berenbaum MC (1978) A method for testing for synergy with any number of agents. J Infect Dis 137: 122–30
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Kerschbaumer, G., Wernsdorfer, G., Wiedermann, U. et al. Synergism between mefloquine and artemisinin and its enhancement by retinol in Plasmodium falciparum in vitro . Wien Klin Wochenschr 122 (Suppl 3), 57–60 (2010). https://doi.org/10.1007/s00508-010-1439-5
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00508-010-1439-5