Mefloquine pharmacokinetics and mefloquine-artesunate effectiveness in Peruvian patients with uncomplicated Plasmodium falciparum malaria

<p>Abstract</p> <p>Background</p> <p>Artemisinin-based combination therapy (ACT) is recommended as a means of prolonging the effectiveness of first-line malaria treatment regimens. Different brands of mefloquine (MQ) have been reported to be non-bioequivalent; this could result in sub-therapeutic levels of mefloquine with decreased efficacy. In 2002, mefloquine-artesunate (MQ-AS) combination therapy was adopted as the first-line treatment for uncomplicated <it>Plasmodium falciparum </it>malaria in the Amazon region of Peru. Although MQ resistance has yet to be reported from the Peruvian Amazon, it has been reported from other countries in the Amazon Region. Therefore, continuous monitoring is warranted to ensure that the first-line therapy remains efficacious. This study examines the <it>in vivo </it>efficacy and pharmacokinetic parameters through Day 56 of three commercial formulations of MQ (Lariam^®, Mephaquin^®, and Mefloquina-AC^®Farma) given in combination with artesunate.</p> <p>Methods</p> <p>Thirty-nine non-pregnant adults with <it>P. falciparum </it>mono-infection were randomly assigned to receive artesunate in combination with either (1) Lariam, (2) Mephaquin, or (3) Mefloquina AC. Patients were assessed on Day 0 (with blood samples for pharmacokinetics at 0, 2, 4, and 8 hours), 1, 2, 3, 7, and then weekly until day 56. Clinical and parasitological outcomes were based on the standardized WHO protocol.</p> <p>Whole blood mefloquine concentrations were determined by high-performance liquid chromatography and pharmacokinetic parameters were determined using non-compartmental analysis of concentration versus time data.</p> <p>Results</p> <p>By day 3, all patients had cleared parasitaemia except for one patient in the AC Farma arm; this patient cleared by day 4. No recurrences of parasitaemia were seen in any of the 34 patients. All three MQ formulations had a terminal half-life of 14–15 days and time to maximum plasma concentration of 45–52 hours. The maximal concentration (C_max) and interquartile range was 2,820 ng/ml (2,614–3,108) for Lariam, 2,500 ng/ml (2,363–2,713) for Mephaquin, and 2,750 ng/ml (2,550–3,000) for Mefloquina AC Farma. The pharmacokinetics of the three formulations were generally similar, with the exception of the C_maxof Mephaquin which was significantly different to that of Lariam (<it>p </it>= 0.04).</p> <p>Conclusion</p> <p>All three formulations had similar pharmacokinetics; in addition, the pharmacokinetics seen in this Peruvian population were similar to reports from other ethnic groups. All patients rapidly cleared their parasitaemia with no evidence of recrudescence by Day 56. Continued surveillance is needed to ensure that patients continue to receive optimal therapy.</p

Estudio de bioequivalencia del ibuprofeno 400 mg tabletas

Objective. To determine the bioavailability of two dosage forms of ibuprofen 400mg tablets, for establishing if the multisource (generic) drug is bioequivalent to the reference (Motrin® 400mg tablets). Materials and methods. It was designed an opened study, randomized, two periods, cross over, and seven days washout period, with 12 healthy volunteers (male and female), between 21 and 48 years old, who have taken one tablet of the multisource or reference tablets; according to randomization; with 200 mL of water. After drug intake 4 mL of blood was collected from each volunteer, for quantification of ibuprofen. The plasma samples with ibuprofen and sodium diclofenac (internal standard) were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) with negative ion electrospray ionization using selected reaction monitoring. The bioequivalence was established with pharmacokinetics parameters: area under the curve AUC(0-t), AUC(0-∞) and maximum concentration (Cmax). Results. According to statistical analysis were founded: AUCmultisource(0-t) = 86.85 (ug*h)/mL, AUCRef.(0-t) = 81.20 (ug*h)/mL, AUCmultisource(0-∞) = 88.67 (ug*h)/mL, AUCRef.(0-∞) = 82.83 (ug*h)/mL, Cmáxmultisource = 17.70 ug/mL, CmáxRef.=18.09 ug/mL, with intervals of 0.93-1.24 for AUC(0-t), 0.93-1.24 for AUC(0-∞) and 0.81-1.19 for Cmax. Conclusions. The values founded for AUC(0-t), AUC(0-∞) and Cmax are within the established limits by WHO and FDA (0,80 -1,25), so ibuprofen 400mg tables; multisource drug, is bioequivalent to Motrin 400mg tablets, with regard to both the rate and extent of absorption.Objetivo. Determinar la biodisponibilidad de dos formulaciones de ibuprofeno 400mg tabletas, para establecer si el medicamento multifuente (genérico) es bioequivalente al de referencia (Motrin® 400mg). Materiales y métodos. Se diseñó un estudio abierto, randomizado, cruzado, dos periodos, con siete días de lavado, con 12 voluntarios sanos de ambos sexos, entre 21 y 48 años, quienes ingirieron una tableta del medicamento genérico o de referencia, según randomización, con 200mL de agua. Luego de ingerir el medicamento se colectó 4mL de sangre por voluntario para la cuantificación plasmática de ibuprofeno. Las muestras de plasma se analizaron por cromatografía líquida acoplada al espectrofotómetro de masas (LC-MS/MS) con ionización electrospray ión negativo, aplicando monitoreo de reacción selectiva. La bioequivalencia se determinó con los parámetros farmacocinéticos de área bajo la curva AUC(0-t), AUC(0-∞) y concentración máxima (Cmax). Resultados. Según análisis estadístico, se encontraron: AUCmultifuente(0-t) = 86,85 (μg*h)/ mL, AUCRef.(0-t)= 81,20 (μg*h)/mL, AUCmultifuente(0-∞) = 88,67 (μg*h)/mL, AUCRef.(0-∞) = 82,83(μg*h)/mL, Cmáxmultifuente = 17,70 ug/mL, CmáxRef. =18,09 μg/mL, con rango de 0,93-1,24 para AUC(0-t), 0,93-1,24 para AUC(0-∞) y 0,81-1,19 para Cmax. Conclusión. Los valores encontrados de ibuprofeno están dentro de los requisitos de la OMS y la FDA, para establecer bioequivalencia (0,80–1,25), demostrándose que el ibuprofeno genérico es bioequivalente al de referencia en velocidad y cantidad de ibuprofeno absorbido en el organismo

Estudio de bioequivalencia del ibuprofeno genérico 400mg tabletas

Objetivo. Determinar la biodisponibilidad de dos formulaciones de ibuprofeno 400mg tabletas, para establecer si el medicamento multifuente (genérico) es bioequivalente al de referencia (Motrin® 400mg). Materiales y métodos. Se diseñó un estudio abierto, randomizado, cruzado, dos periodos, con siete días de lavado, con 12 voluntarios sanos de ambos sexos, entre 21 y 48 años, quienes ingirieron una tableta del medicamento genérico o de referencia, según randomización, con 200mL de agua. Luego de ingerir el medicamento se colectó 4mL de sangre por voluntario para la cuantificación plasmática de ibuprofeno. Las muestras de plasma se analizaron por cromatografía líquida acoplada al espectrofotómetro de masas (LC-MS/MS) con ionización electrospray ión negativo, aplicando monitoreo de reacción selectiva. La bioequivalencia se determinó con los parámetros farmacocinéticos de área bajo la curva AUC(0-t), AUC(0-∞) y concentración máxima (Cmax). Resultados. Según análisis estadístico, se encontraron: AUCmultifuente(0-t) = 86,85 (μg*h)/ mL, AUCRef.(0-t)= 81,20 (μg*h)/mL, AUCmultifuente(0-∞)= 88,67 (μg*h)/mL, AUCRef.(0-∞)= 82,83(μg*h)/mL, Cmαxmultifuente = 17,70 ug/mL, CmαxRef. =18,09 μg/mL, con rango de 0,93-1,24 para AUC(0-t), 0,93-1,24 para AUC(0-∞) y 0,81-1,19 para Cmax. Conclusión. Los valores encontrados de ibuprofeno están dentro de los requisitos de la OMS y la FDA, para establecer bioequivalencia (0,80-1,25), demostrándose que el ibuprofeno genérico es bioequivalente al de referencia en velocidad y cantidad de ibuprofeno absorbido en el organismo