Partial in vivo protection against Peruvian spider Loxosceles laeta venom by immunization with a multiepitopic protein (rMEPLox).

Loxoscelism is a serious public health problem in Peru, with approximately 2500 accidents reported per year. To envision alternatives to cope with this health problem, the neutralizing humoral immune response against the lethal effects of Peruvian spider Loxosceles laeta venom was evaluated in a mouse model by immunization with a non-toxic multiepitopic protein (rMEPLox). This immunogen contains epitopes from an astacin-like metalloprotease, a hyaluronidase and a sphingomyelinase-D from Loxosceles intermedia and from SMase-I from L. laeta venoms. In vivo protection assays showed that five out of six mice immunized with rMEPLox (after six injections) resisted to 1.4 LD50 of L. laeta venom, whereas only two animals from a control group survived. The present results indicates that this multiepitopic protein can be a promising candidate for anti-loxoscelic antivenom production and experimental vaccination approaches.

Estudio de bioequivalencia del ibuprofeno 400 mg tabletas / Bioquivalence study of ibuprofen 400 mg tablets

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), UC(0-∞) y concentración máxima (Cmax). Resultados. Según análisis estadístico, se encontraron: AUC multifuente(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 (0,80û1,25), demostrándose que el ibuprofeno genérico es bioequivalente al de referencia en velocidad y cantidad de ibuprofeno absorbido en el organismo.

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.