In vitro transdermal drug permeation tests: a regulatory scenario evaluation

SUMMARY Introduction: The Transdermal Drug Delivery Systems (TDDS) could circumvent the inconveniences of oral administration, increasing treatment adhesion. Meanwhile, despite being highly widespread systems, there are discrepancies between the performance and quality control methodologies recommended by the leading regulatory agencies, which is an issue for the pharmaceutical industry. Aim: To identify and to compare the requirements for TDDS regulatory approval by important agencies, focusing on the in vitro release and drug permeation studies, which are crucial tests for the evaluation of safety, efficacy, and performance of these systems. Methods: The documents that regulate the scope of TDDS in FDA, EMA and Anvisa were analyze, as well as the contributions of OECD. In addition, an approaching regarding the pharmacopeial requirements was made regarding USA, Europe, and Brazil. Results and conclusion: Concerning the regulatory approval aspects, the FDA is reviewing its documents because the current guidance is not specific to transdermal systems. On the other hand, the EMA presents a unique guideline that includes specific requirements for TDDS. The USA and the European Pharmacopoeias have specific mentions to performance and quality control of TDDS, while the Brazilian Pharmacopoeia does not mention this dosage form. Recently, Anvisa published a guide, which helps Brazilian manufacturers concerning the tests required for the regulatory approval of a new TDDS. The launch of this standardized national statute associated with the use of a validated in vitro release and permeation tests represents a remarkable breakthrough regarding TDDS.

Introducción: los sistemas de administración de fármacos transdérmicos (TDDS) podrían sortear los inconvenientes de la administración por vía oral, aumentando la adherencia al tratamiento. Mientras tanto, a pesar de ser sistemas muy extendidos, existen discrepancias entre las metodologías de desempeño y control de calidad recomendadas por las principales agencias reguladoras, lo cual es un problema para la industria farmacéutica. Objetivo: identificar y comparar los requisitos para la aprobación regulatoria de TDDS por parte de las principales agencias reguladoras, enfocándose en los estudios de liberación in vitro y premiación de fármacos. Métodos: se analizaron los documentos que regulan el alcance de la TDDS en la FDA, EMA y Anvisa, así como los aportes de la OCDE. Además, se realizó un planteamiento sobre los requisitos de las farmacopeas de los Estados Unidos, Europa y Brasil. Resultados y conclusión: la FDA está revisando los aspectos de aprobación regulatoria porque la guía actual no es específica para los sistemas transdérmicos. Por otro lado, la EMA presenta una guía única que incluye requisitos específicos para TDDS. Las farmacopeas de los Estados Unidos e Europa tienen menciones específicas al rendimiento y control de calidad de TDDS, mientras que la Farmacopea brasileña no menciona esta forma de dosificación. Recientemente, Anvisa publicó una guía que ayuda a los fabricantes brasileños en cuanto a las pruebas requeridas para la aprobación regulatoria de un nuevo TDDS. El lanzamiento de este estatuto nacional estandarizado asociado con el uso de pruebas validadas de liberación y premiación in vitro representa un avance notable con respecto a TDDS.

Introdução: os sistemas de liberação transdérmica (SLT) são capazes de contornar as desvantagens da administração oral de medicamentos, aumentando a adesão ao tratamento. Entretanto, apesar de serem sistemas difundidos, existem discrepâncias entre as metodologias de desempenho e controle de qualidade recomendadas pelas agências regulatórias, dificultando o desenvolvimento destes pela indústria farmacêutica. Objetivo: identificar e comparar os requisitos para aprovação regulatória de SLT por importantes agências regulatórias, com foco nos estudos de liberação e permeação de fármacos in vitro, testes fundamentais para avaliação da segurança, eficácia e desempenho desses sistemas. Métodos: foram analisados os documentos que regulam o escopo dos SLT publicados pela FDA, EMA e Anvisa e as contribuições da OCDE. Além disso, foi realizada a abordagem sobre os requisitos farmacopeicos nos Estados Unidos, Europa e Brasil. Resultados e conclusão: FDA está revisando os aspectos de aprovação regulatória, pois os documentos atuais não são específicos para os SLT. Em contraponto, a EMA apresenta uma diretriz única que inclui requisitos específicos para estes sistemas. Em relação às farmacopeias, enquanto EUA e Europa apresentam recomendações específicas para desempenho e controle de qualidade dos SLT, a Farmacopeia brasileira não menciona esta forma farmacêutica. Recentemente, a Anvisa publicou um guia com os testes necessários para o registro destes sistemas. O lançamento de tal publicação, associado a ensaios devidamente validados representam um avanço notável no escopo regulatório dos SLT.

The pulmonary route as a way to drug repositioning in COVID-19 therapy.

INTRODUCTION: The outbreak of the disease caused by the new coronavirus (COVID-19) has been affecting society's routine and its patterns of interaction worldwide, in addition to the impact on the global economy. To date, there is still no clinically effective treatment for this comorbidity, and drug repositioning might be a good strategy considering the established clinical safety profile. In this context, since COVID-19 affects the respiratory tract, a promising approach would be the pulmonary drug delivery. OBJECTIVE: Identify repurposing drug candidates for the treatment of COVID-19 based on the data of ongoing clinical trials and in silico studies and also assess their potential to be applied in formulations for pulmonary administration. METHOD: A integrative literature review was conducted between June and July 2020, by extracting the results from Clinical Trials, PubMed, Web of Science and Science Direct databases. RESULTS: By crossing the results obtained from diverse sources, 21 common drugs were found, from which only 4 drugs presented studies of pulmonary release formulations, demonstrating the need for greater investment and incentive in this field. CONCLUSION: Even though the lung is a target that facilitates viral infection and replication, formulations for pulmonary delivery of suitable drugs are still lacking for COVID-19 treatment. However, it is indisputable that the pandemic constitutes a concrete demand, with a profound impact on public health, and that, with the appropriate investments, it will give the pharmaceutical industry an opportunity to reinforce the pulmonary delivery field.

Galenic approaches in troubleshooting of glibenclamide tablet adhesion in compression machine punches.

This study aimed to examine the adhesion of glibenclamide 5 mg tablets to the tools of compression machines. This problem is not commonly reported in the literature, since it is considered as tacit knowledge. The starting point was the implementation of three technical alternatives: changing the parameters of compression, evaluating the humidity of the powder blend and the manufacturer of the lubricant magnesium stearate. The adhesion was directly related to the characteristics of magnesium stearate from different manufacturers, and the feasibility of evaluating powder flow characteristics by different techniques that are not routinely followed in various pharmaceutical companies. In vitro dissolution tests showed that the magnesium stearate manufacturer can influence on the dissolution profile of glibenclamide tablets. This study presented various aspects of tablet adhesion to compression machine punches. Troubleshooting approaches can be, most of times, conducted based on previous experience, or an experimental research needs to be implemented in order to have confident results.