Bioequivalence of metformin hydrochloride sustained-release tablets under fed condition in healthy subjects / 中国药科大学学报

@#To evaluate bioequivalence and safety of two kinds of metformin hydrochloride sustained-release tablets (test preparation vs reference preparation) under the condition of fed and single administration.A single center, randomized, open, single-dose, two-period, two-sequence, and double-crossover design was used.32 healthy subjects took 0.5 g of test preparation or reference preparation under fed and single-dose administration.4 mL of venous blood was collected from before administration (0 h) to 1, 3, 4, 4.5, 5, 5.5, 6, 7, 8, 9, 10, 12, 15, 24, 36 and 48 h after administration.The concentration of metformin in plasma samples was detected, and then the pharmacokinetic parameters were calculated by WinNonlin 7.0 software.When the 90% confidence intervals of cmax, AUC0-t and AUC0-∞ geometric mean ratio of test preparation and reference preparation were within 80.00%-125.00% equivalent intervals respectively, the bioequivalence of the two preparations was proved.One subject fell off due to adverse events.The main pharmacokinetic parameters of test preparation and reference preparation as follows: cmax were (0.68 ± 0.14) and (0.65 ± 0.11) mg/L, AUC0-t were (7.33 ± 1.65) and (7.00 ± 1.89) h·mg/L, AUC0-∞ were (7.39 ± 1.67) and (7.06 ± 1.91) h·mg/L, respectively.The 90% confidence intervals of the geometric mean ratio of the two main pharmacokinetic parameters were 101.45%-109.14%, 100.08%-112.32% and 100.24%-112.28%, respectively, which fell within the bioequivalence interval of 80.00%-125.00%.There were no serious adverse events and unexpected adverse events during the trial.The results show that test preparation and reference preparation are bioequivalent under fed and single-dose administration, safe and well tolerated in healthy subjects.

Equivalencia terapéutica evaluada mediante estudios in vitro de medicamentos multifuentes: estudio de casos de amoxicilina, doxiciclina y fluconazol en Lima, Perú / Therapeutic equivalence evaluated by in vitro studies of multisource pharmaceutical products: case studies of amoxicillin, doxycycline and fluconazole in Lima, Peru

RESUMEN El objetivo del estudio fue determinar la equivalencia terapéutica evaluada mediante estudios in vitro de cuatro marcas de medicamentos conteniendo amoxicilina, doxiciclina y fluconazol adquiridos en establecimientos farmacéuticos de Lima Metropolitana y establecer su intercambiabilidad con un producto de referencia (PR). Se empleó un método validado de espectrofotometría ultravioleta visible para determinar el perfil de disolución. El factor de similitud (f2) se utilizó para establecer la equivalencia terapéutica, considerándose equivalentes si los valores de f2 se encontraban entre 50 y 100. Para doxiciclina los cuatro medicamentos fueron equivalentes in vitro al PR, para amoxicilina sólo dos medicamentos fueron equivalentes in vitro al PR y para fluconazol ninguno fue equivalente in vitro al PR. Se concluye que algunos medicamentos de amoxicilina y fluconazol que circulan en el mercado nacional no cumplen con la equivalencia terapéutica evaluada mediante estudios in vitro; es decir, no son intercambiables.

ABSTRACT The objective of the study was to determine the therapeutic equivalence evaluated through in vitro studies of four brands of drugs containing amoxicillin, doxycycline, and fluconazole purchased at pharmaceutical facilities in Metropolitan Lima, and to establish their interchangeability with a reference product (RP). A validated method of visible ultraviolet spectrophotometry was used to determine the dissolution profile. The similarity factor (f2) was used to establish the therapeutic equivalence, being considered equivalent if the values of f2 were between 50 and 100. For doxycycline, the four drugs were equivalent in vitro to the RP; for amoxicillin, only two drugs were equivalent in vitro to the RP; and for fluconazole, none was equivalent in vitro to the RP. It is concluded that some amoxicillin and fluconazole drugs circulating in the national market do not meet the therapeutic equivalence assessed by in vitro studies; in other words, they are not interchangeable.

Evaluación de la intercambiabilidad in vitro de diferentes marcas de tabletas de diclofenaco sódico disponibles en el mercado colombiano / In vitro evaluation of the interchangeability of different brands of diclofenac sodium tablets available in the Colombian market

Introducción. El diclofenaco sódico se clasifica como un antiinflamatorio no esteroide. Dado que es de venta libre, el paciente no tiene ningún seguimiento por parte de los equipos de salud, y como sus fuentes son múltiples, es necesario establecer la equivalencia entre ellas en estudios in vitro, que son los más prácticos y plantean un menor compromiso ético. Objetivos. Determinar la intercambiabilidad de diferentes marcas comerciales de diclofenaco sódico comparadas con el producto innovador mediante un estudio in vitro de tabletas comerciales de 50 mg, según los lineamientos del Sistema de Clasificación Biofarmacéutica (SCB). Materiales y métodos. Se desarrollaron pruebas físicas y químicas siguiendo las indicaciones de laedición 39 de la United States Pharmacopeia (USP). Para la cuantificación, se validó una metodología analítica según lo establecido en la mencionada farmacopea y la guía Q2 del International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH). Los perfiles de disolución y sus análisis se rigieron por lo establecido por la Organización Mundial de la Salud y las normas nacionales. Resultados. Todos los productos aprobaron las pruebas físicas. En cuanto a la disolución, la etapa ácida también fue superada por todas las marcas, pero una marca falló en la etapa alcalina. El análisis de similitud reveló que solo un producto fue equivalente al innovador y tres fueron supradisponibles, aunque dichas marcas también podrían considerarse equivalentes al producto innovador. Conclusiones. De las ocho marcas evaluadas, tres no cumplieron totalmente con la prueba de valoración del principio activo y del porcentaje de disolución; solo una marca fue intercambiable con el producto innovador y tres fueron supradisponibles comparadas con este, por lo cual no constituyen un riesgo para el paciente.

Introduction: Diclofenac sodium is classified as a non-steroidal anti-inflammatory drug. As diclofenac is an over-the-counter drug, its use among patients cannot be monitored by health teams in follow-up sessions. Given the multiple sources of diclofenac sodium, their interchangeability must be investigated, particularly in the form of in vitro studies, which are the most practical research type and entail minimal ethical commitment. Objectives: To determine the interchangeability of the different commercial brands of diclofenac sodium relative to the innovative product, this work carries out an in vitro study of eight commercial products of diclofenac sodium (50 mg) following the guidelines of the Biopharmaceutical Classification System. Materials and methods: Physical and chemical tests were developed following the guidelines of the 39th edition of the United States Pharmacopoeia. An analytical methodology was validated for the quantification of diclofenac according to the current pharmacopoeia and the Q2 guideline ofthe International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH). Dissolution profiles and their analyseswere governed by the regulations established by the World Health Organization and the national regulations. Results: All the products passed the physical tests. In the dissolution assays, the acid stage was overcome by all brands, but in the alkaline stage, one brand failed. The analysis of the similarities revealed that only one product was equivalent to the innovator and that three were supra-available, although these brands could also be considered equivalent to the innovator. Conclusions: Of the eight brands evaluated, three failed the test forthe active principle and the percentage of dissolution. Only one brand was found to be interchangeable with the innovator, and three were identified to besupra-availableand, thus, they do not present a risk for patients.

Generic substitution in Malaysia: Recommendations from a systematic review.

Generic substitution is the act of switching from a branded drug to its therapeutically equivalent generic version. This study aims to systematically review the literature with regards to generic substitution around the globe. Studies compared generic and brand-name drugs for clinical efficacy and cost effectiveness. The current findings show that the new policies are aimed at supporting the development of the generics industry in the respective countries. Further investigation is needed to explore the implementation of the current generic substitution policies and how to increase their accessibility to the general population. Generic substitution policies comparison between countries were conducted among 9 countries, that is, Australia, Canada, Czech Republic, Ireland, Japan, Switzerland, Indonesia, United State and United Kingdom. From 27 journals that were reviewed, only 14 were selected based on the fulfilled criteria appropriate to the journals that we had searched. All these policies were then studied to propose recommendations for generic substitution.

The importance of bioequivalence study: focus on clopidogrel.

Bioequivalence (BE) study is required to show whether a generic copy product can be interchangeable with the brand innovator product. The aim of this article is to provide the rationale for conducting BE studies, the main products requiring BE studies, the design and conduct of BE studies in general, with focus on clopidogrel. All of the clopidogrel generic products in Indonesia have been shown to be BE to the innovator product Plavix® and they contain API (active pharmaceutical ingredient) clopidogrel form 1 that complies with USP 30, 1997 requirements: the R-enantiomer content is not more than 1%. A proof that bioequivalence (BE) means therapeutic equivalence (TE) is also provided for cardiovascular drugs. Clopidogrel has 2 polymorphic forms, form 1 and form 2, which have the same indications. At least one pivotal study of clopidogrel, CAPRIE, used clopidogrel form 1. An atherothrombotic event may be associated with clopidogrel resistance, which occur in about 4 to 30% of patients treated with conventional doses of clopidogrel.

Study on the Relative Bioavailability of Yifuxian'an Capsules in Human Body / 中国药房

OBJECTIVE:To study the relative bioavailability of yifuxian'an capsules.METHODS:Concentrations of ri-fampicin,isoniazid and pyrazinamide in plasma were determined on12volunteers respectively after a single oral dose of yifux-ian'an capsules(tested preparations)and rifater(reference preparation)by RP-HPLC method;the pharmacokinetics parame-ters were processed by3p97process.RESULTS:The AUC 0～t of the tested preparation and reference substance of rifampicin were(70.69?36.32)and(70.77?32.26)(?g?h)/ml respectively,t max of which were(1.82?0.28)and(1.79?0.25)h re-spectively,C max of which were(12.83?4.98)?g/ml and(12.84?3.95)?g/ml respectively;The AUC 0～t of which were(14.30?8.25)and(13.76?6.16)(?g?h)/ml respectively,t max of which were(1.54?0.36)and(1.58?0.38)h respectively,C max of which were(5.42?2.52)and(5.46?2.46)?g/ml respectively;The AUC 0～t of which of pyrazinamide were(243.56?128.98)and(238.07?117.63)(?g?h)/ml respectively,t max of which were(1.58?0.64)and(1.69?0.55)h respectively,C max of which were(29.45?12.45)and(27.46?11.02)?g/ml respectively.The relative bioequivalence of rifampicin,isoniazid and pyrazi-namide of the tested preparation were(99.88?12.92)%,(103.84?24.10)%and(102.57?12.31)%respectively.CONCLU-SION:Bioavailability of the2preparations are bioequivalent.