A oferta pública de medicamentos para aids e o papel de Farmanguinhos / Public supply of AIDS drugs and the role of Farmanguinhos

Resumo Este artigo descreve e analisa a participação do Instituto de Tecnologia em Fármacos (Farmanguinhos) na produção local de medicamentos antirretrovirais no Brasil. São também apresentadas as mudanças no padrão de provimento, a situação das parcerias para o desenvolvimento produtivo e a posição dos produtores nacionais para esses medicamentos. As estratégias metodológicas foram revisão bibliográfica, análise de documentos oficiais e dados fornecidos por Farmanguinhos e pelo Departamento de Condições Crônicas e Infecções Sexualmente Transmissíveis do Ministério da Saúde, via Lei de Acesso à Informação. Este artigo mostra que o estabelecimento das parcerias abriu novas perspectivas para o desenvolvimento da política de oferta pública de antirretrovirais para as pessoas vivendo com HIV, por contribuir para a sustentabilidade das despesas financeiras do Ministério da Saúde com medicamentos. Farmanguinhos é o laboratório público que fornece mais quantidades e recebe os maiores valores provenientes do fornecimento desses produtos ao Ministério da Saúde. Embora os medicamentos importados preponderem largamente em quantidade e valores pagos pelo Ministério da Saúde, Farmanguinhos permanece sendo um provedor fundamental na produção local de antirretrovirais. Apesar dos problemas verificados nas Parcerias, os ganhos nas competências tecnológicas na produção de antirretrovirais podem ampliar o horizonte tecnológico e produtivo do laboratório.

Abstract This article describes and analyses the part played by the Instituto de Tecnologia em Fármacos (Farmanguinhos) in local production of antiretroviral medicines in Brazil, as well as changes in the pattern of supply, the status of related Production Development Partnerships and the position of Brazilian producers of these medicines. The methodological strategies used were literature review and analysis of official documents and data provided by Farmanguinhos and by the Ministry of Health's Department of Chronic Conditions and Sexually Transmitted Infections, via the Information Access Law. This article shows that, by contributing to the sustainability of Ministry of Health expenditure on medicines, these partnerships have opened new prospects for developing the policy of public supply of antiretrovirals for people living with HIV. Farmanguinhos is the public laboratory that supplies the largest quantities of these products to the Ministry of Health and receives the largest revenues from supplying them. Although the imported medicines supplied to the Ministry of Health account for much larger quantities and revenues, Farmanguinhos continues to be a fundamentally important supplier of locally produced antiretrovirals. Despite the problems found in establishing the partnerships, the gains in antiretroviral production technology competences can broaden the laboratory's technological and production horizons.

Avaliação dos mecanismos envolvidos na permeabilidade de fármacos antirretrovirais por meio dos modelos ex vivo ( células de Franz ) e in vitro ( PAMPA ) / Evaluation of mechanisms involved in the permeability of antiretroviral drugs through ex vivo ( Franz cells ) and in vitro ( PAMPA ) models

Para fármacos administrados por via oral, o controle da extensão e da velocidade de absorção depende basicamente de duas importantes etapas: solubilidade do fármaco nos líquidos fisiológicos e sua permeabilidade através das membranas biológicas. Assim, o Sistema de Classificação Biofarmacêutica (SCB) foi proposto como uma ferramenta para o desenvolvimento de novos fármacos, de novas formulações e para auxiliar nos processos de bioisenção. No entanto, outro fator relacionado à biodisponibilidade e que deve ser considerado nos estudos biofarmacêuticos é o metabolismo. Desta forma, o Sistema de Classificação Biofarmacêutica de Distribuição de Fármacos (SCBDF) foi proposto com a finalidade de classificar os fármacos de acordo com suas características de solubilidade e de metabolismo de modo que seja possível avaliar e predizer o comportamento do fármaco in vivo. O metabolismo tem sido amplamente investigado, sobretudo as enzimas do citocromo P450, as quais estão presentes também nos enterócitos. Além disso, o SCBDF oferece um suporte quanto à avaliação dos mecanismos de permeabilidade envolvidos nos processos de absorção, interações fármaco-fármaco e interações fármaco-alimento. Assim, o presente trabalho teve como objetivo elucidar os mecanismos envolvidos na permeabilidade de fármacos antirretrovirais por meio dos modelos ex vivo (câmaras de difusão vertical tipo Franz) e in vitro (PAMPA, MDCK-MDR1 e microssomas) considerando os aspectos relacionados ao metabolismo intestinal e ao efluxo destes fármacos. Dada a importância da utilização de fármacos antirretrovirais na terapia medicamentosa contra a Síndrome da Imunodeficiência Adquirida (SIDA) e que estes medicamentos são normalmente administrados cronicamente, a compreensão dos mecanismos envolvidos na permeabilidade é de suma importância, uma vez que estes não estão totalmente esclarecidos e poucas informações são encontradas na literatura. Além disso, a biodisponibilidade de fármacos como estavudina, lamivudina e zidovudina indica variação na permeabilidade, necessitando de uma investigação científica mais aprofundada dos processos absortivos. Assim, segmentos de jejuno provenientes de ratos machos Wistar foram utilizados para a avaliação da permeabilidade intestinal dos referidos antirretrovirais considerando a avaliação de efluxo pela glicoproteína-P e o metabolismo intestinal pela CYP3A. De maneira complementar, estudos in vitro com o emprego de membranas artificiais paralelas (PAMPA) e culturas celulares de MDCK-MDR1 foram realizados com a finalidade de auxiliar na elucidação dos mecanismos de permeabilidade dos fármacos antirretrovirais. Além disso, a avaliação do metabolismo dos referidos fármacos foi realizada com o emprego de microssomas a fim de verificar se tais substâncias são substratos de enzimas da família CYP3A e, assim, verificar o impacto do metabolismo intestinal na absorção. Os resultados de permeabilidade obtidos em PAMPA foram: 0,74±0,11 x 10-6 cm/s para a estavudina, 0,25±0,12 x 10-6 cm/s para a lamivudina e 1,14±0,25 x 10-6 cm/s para a zidovudina. Já no modelo ex vivo com o emprego de câmaras de difusão vertical tipo Franz, os resultados foram: 1,56±0,32 x 10-5 cm/s para a estavudina, 1,26±0,27 x 10-5 cm/s para a lamivudina e 2,54±0,49 x 10-5 cm/s para a zidovudina. Portanto, com base nos resultados obtidos a partir dos dois métodos empregados, sugere-se que 30 outro mecanismo de transporte que não envolva a permeabilidade por difusão transcelular passiva possa estar relacionado à permeabilidade dos fármacos antirretrovirais. Com relação aos estudos de efluxo, os resultados obtidos a partir dos experimentos realizados em câmaras de difusão vertical tipo Franz demonstraram o aumento significativo da permeabilidade dos três antirretrovirais quando o inibidor de P-gp foi empregado, sendo: de 15,6 x 10-6 para 42,5 x 10-6 cm/s para a estavudina, de 12,6 x 10-6 para 37,5 x 10-6 cm/s para a lamivudina e de 25,4 x 10-6 para 56,6 x 10-6 cm/s para a zidovudina. Em culturas celulares MDCK-MDR1, os resultados de permeabilidade foram utilizados para a obtenção das razões entre as direções B→A e A→B. Os valores de Papp na condição inibida para os fármacos estudados apresentaram razão menor do que 1. Já a razão B→A/A→B para cada fármaco nos ensaios sem inibidor apresentou-se igual ou maior que 2, evidenciando a interação fármaco-transportador. Com base nisso, o modelo ex vivo com o emprego de segmentos intestinais em câmaras de difusão vertical tipo Franz apresentou-se adequado na avaliação do mecanismo de efluxo dos fármacos antirretrovirais, o que foi confirmado com os estudos realizados em MDCK-MDR1. Assim, os fármacos antirretrovirais estudados apresentaram interação significativa com a P-gp. Em relação aos estudos de metabolismo realizados em câmaras de difusão vertical tipo Franz, os resultados demonstraram grande variação na permeabilidade dos três antirretrovirais quando o inibidor de CYP3A foi empregado, sendo: de 15,6 x 10-6 para 23,5 x 10-6 cm/s para a estavudina, de 12,6 x 10-6 para 27,3 x 10-6 cm/s para a lamivudina e de 25,4 x 10-6 para 40,5 x 10-6 cm/s para a zidovudina. Já no modelo que emprega microssomas, os resultados de metabolização na ausência e na presença de inibidor de CYP3A foram: de 16,56% para 19,79% para a estavudina, de 14,56% para 15,55% para a lamivudina e de 17,85% para 16,48% para a zidovudina. Com base nisso, sugerese o emprego de microssomas para a determinação de metabolismo, uma vez que o método ex vivo empregado demonstrou grande variação entre os valores obtidos. Desta forma, observou-se que, para cada fármaco, não houve influência significativa no metabolismo pré-sistêmico relacionado às enzimas do complexo CYP3A, o que indica que a absorção oral das referidas substâncias não é limitada por tais enzimas. Portanto, a utilização dos diferentes métodos empregados no desenvolvimento do presente trabalho permitiu compreender os mecanismos envolvidos no transporte dos fármacos antirretrovirais, o que se torna de grande relevância nas etapas de desenvolvimento farmacêutico de novas moléculas e na compreensão de eventos clínicos ainda não esclarecidos atualmente

For orally administered drugs, control of the extent and rate of absorption depends on two important steps: solubility of the drug in physiological liquids and their permeability across biological membranes. Thus, the Biopharmaceutics Classification System (BCS) has been proposed as a tool for the development of new drugs, new formulations and aid in the biowaiver processes. However, another factor related to bioavailability that should be considered in biopharmaceutic studies is the metabolism. Thus, the Biopharmaceutics Drug Disposition Classification System (BDDCS) has been proposed for drug classification according to their solubility and metabolism characteristics, so it is possible to evaluate and predict the in vivo behavior of a compound. Metabolism has been extensively investigated, especially cytochrome P450 enzymes, which are also expressed in enterocytes. Besides, BDDCS provides support in evaluating the permeability mechanisms involved in the absorption processes, drug-drug interactions and drug-food interactions. Thus, the present study aimed to evaluate the mechanisms of permeability of antiretroviral drugs through the ex vivo (Franz cells) and in vitro (PAMPA, MDCK-MDR1 and microsomes) models considering aspects related to the intestinal metabolism and efflux of these drugs. Given the importance of the use of antiretroviral drugs in drug therapy against Acquired Immune Deficiency Syndrome (AIDS) and that these drugs are usually administered in a long-term way, understanding the mechanisms involved in the permeability is of a great importance, since they are not totally elucidated and no information is found in the literature. In addition, drugs as stavudine, lamivudine and zidovudine indicate variation in the permeability, which require further scientific investigation of absorptive processes. Thus, jejunum segments from rats were used to evaluate the intestinal permeability of these antiretroviral drugs, considering the evaluation of efflux by P-glycoprotein and intestinal metabolism by CYP3A. In a complementary manner, in vitro studies using parallel artificial membranes (PAMPA) and cell cultures MDCK-MDR1 were performed to aid in the elucidation of the permeability mechanisms of antiretroviral drugs. Also, the evaluation of the metabolism was carried out using microsomes to verify if such substances are substrates of CYP3A, and verify the impact of the intestinal metabolism in the absorption. The permeability results obtained in PAMPA were: 0.74±0.11x10-6 cm/s for stavudine, 0.25±0.12x10-6 cm/s for lamivudine and 1.14±0.25x10-6 cm/s for zidovudine. In ex vivo method using the intestinal segments in Franz cells, the results were: 1.56±0.32x10-5 cm/s for stavudine, 1.26±0.27x10-5 cm/s for lamivudine and 2.54±0.49x10-5 cm/s for zidovudine. Thus, based on the results obtained from these two methods, it is suggested that the antiretroviral drugs present other transport mechanism that is different from transcellular passive diffusion. For efflux studies, results obtained from experiments performed in Franz cells shown the increase of the permeability of the three antiretroviral drugs when the P-gp inhibitor was used: from 15.6x10-6 to 42,5x10-6 cm/s for stavudine, from 12.6x10-6 cm/s to 37.5x10-6 cm/s for lamivudine, and 25.4x10-6 to 56.6x10-6 cm/s for zidovudine. In MDCK-MDR1, the permeability results were used for obtaining ratio values between the directions B→A and A→B. The Papp values obtained with 33 inhibitor shown a ratio less than 1. For ratio B→A/A→B for each drug in experiments without inhibitor, the values obtained was equal or greater than 2, which shows the interaction between drug and transporter. Based on that, the ex vivo model using intestinal segments in Franz cells seems to be adequate for evaluation of efflux mechanism of antiretroviral drugs, which was confirmed by MDCK-MDR1 studies. Thus, the antiretroviral drugs presented interaction with P-gp. For metabolism studies in intestinal segments in Franz cells, a wide range of standard deviation was observed for the three antiretroviral drugs when the CYP3A inhibitor was used: from 15.6x10-6 cm/s to 23.5x10-6 cm/s for stavudine, from 12.6x10-6 cm/s to 27.3x10-6 cm/s for lamivudine, and from 25.4x10-6 cm/s to 40.5x10-6 cm/s for zidovudine. In experiments in microsomes, the results of metabolization in the absence and presence of CYP3A inhibitor were: from 16.56 to 19.79% for stavudine, from 14.56 to 15.55% for lamivudine and from 17.85 to 16.48% for zidovudine. Based on that, it is suggested the use of microsomes for metabolism evaluation, since the ex vivo method presented high variability between the results obtained. For each drug, no significative influence in pre-systemic metabolism related to CYP3A enzymes was observed, which indicates that the oral absorption of the drugs is not limited by these enzymes. The use of different methods in this work allowed to understand the mechanisms involved in the transport of antiretroviral drugs, which is of a great relevance in drug development and in the understanding of clinical events currently not clarified

Evaluación del acceso a antirretrovirales en personas viviendo con VIH/SIDA bajo la Ley chilena de garantías explícitas en salud, 1984-2018 / Evaluation of the access to antiretrovirals by people living with hiv/aids under the chilean law of explicit health guarantees, 1984-2018

INTRODUCCIÓN: Las intervenciones estructurales que garantizan el tratamiento antirretroviral (TARV) en la prevención combinada se proponen para cerrar la brecha entre el testeo y el tratamiento, manteniendo a las personas en el continuo de atención. MATERIALES Y MÉTODOS: Experimento natural que utiliza la Ley 19.966 de 2005 que otorga tratamiento y protección financiera a las personas viviendo con VIH/sida (PVVS). Se emplearon datos oficiales agregados del Ministerio de Salud de Chile. Se utilizó un diseño de series de tiempo interrumpidas para determinar el efecto de la intervención en el acceso a antirretrovirales, la morbimortalidad y los casos de sida. Además, se evaluó el impacto de la Ley con un pronóstico empleando un modelo autorregresivo de media móvil (ARIMA), a fin de contrastarlo con los casos observados. RESULTADOS: Después del 2005, se incrementó anualmente el número de PVVS en TARV (2268; IC 95%: 1502,23-3034,31), las defunciones por sida disminuyeron (-17,6; IC 95%: -31,3- -3,8) y los egresos hospitalarios aumentaron (70,86; IC 95%: 9,13-132,59). El pronóstico señaló que, en ausencia de la Ley, de manera estimada 99 321 PVVS (P<0,001) no hubiesen accedido a TARV y se hubiesen presentado 657 casos más de sida (P<0,001). DISCUSIÓN: Con la Ley GES se logró un aumento sustancial del acceso de las PVVS al TARV y una disminución en su morbimortalidad vinculada al incremento en la cobertura. No obstante, la disminución de los casos de sida estaría por debajo de lo esperado debido a brechas en el continuo de atención de las PVVS.

INTRODUCTION: Structural interventions that guarantee antiretroviral treatment (ART) in com-bination prevention are proposed to bridge the gap between testing and treatment, keeping people on the continuum of care. MATERIALS AND METHODS: A experiment that applies Law 19.966 of 2005 that grants treatment and financial protection to people living with HIV/AIDS (PLWHA) was used. Aggregated offi-cial data from the Chilean Ministry of Health were used. An interrupted time-series design was used to determine the effect of the intervention on antiretroviral access, morbidity and mortality, and AIDS cases. Additionally, the impact of the Law was evaluated with projections using an autoregressive moving average model (ARIMA), to contrast it with the observed cases. RESULTS: After 2005, the number of PLWHA on ART increased annually (2,268; 95% CI: 1502,23-3034,31), deaths from AIDS decreased (-17.6; 95% CI: -31,3- -3,8) and hospital discharges increased (70.86; 95% CI: 9.13-132.59). The projections indicated that, in the absence of the Law, an estimate of 99 321 PLWHA (P<0.001) would not have accessed ART and there would have been 657 more cases of AIDS (P<0.001). DISCUSSION: The GES Law achieved a substantial increase in PLWHA access to ART and a de-crease in their morbidity and mortality linked to the increase in coverage. However, the decline in AIDS cases would be lower than expected due to gaps in the continuum of care for PLWHS.

Suministro de antirretrovirales en Argentina: Programa Nacional de Lucha contra los Retrovirus del Humano, SIDA y ETS / Antiretroviral drug supply in Argentina: National Program to Combat Human Retroviruses, AIDS, and STDs

OBJETIVOS: Evaluar el circuito de suministro de antirretrovirales (ARV) dentro del Programa Nacional de Lucha contra los Retrovirus del Humano, SIDA y ETS, mediante indicadores de desempeño, y recuperar la perspectiva de actores involucrados en el circuito de provisión. Se busca mejorar las acciones programáticas satisfaciendo las necesidades de los pacientes. MÉTODOS: En el servicio de farmacia de dos hospitales de Rosario, Argentina, de abril a septiembre de 2005 se llevó a cabo una investigación evaluativa con un abordaje cuantitativo, mediante indicadores y basado en fuentes secundarias, y otro cualitativo, con entrevistas semiestructuradas. RESULTADOS: Los indicadores revelan el impacto de las interrupciones en la provisión de ARV desde el Programa (nivel central) y la acumulación de stock en el nivel local para paliar esas faltas. Los cambios de tratamiento con ARV representan más de 50 por ciento de las prescripciones. El cumplimiento en el retiro de ARV se aleja del valor de referencia. Los entrevistados describieron estrategias alternativas para superar dificultades de comunicación entre niveles, acumular stock, garantizar disponibilidad y acortar tiempos de espera; se establecieron acuerdos informales ante la falta de normativas y la escasez de recursos humanos; las instancias jurisdiccionales (central, intermedia y local o municipal) suman dificultades, y se reconocen esfuerzos del nivel local para mejorar la gestión. CONCLUSIONES: Estos hallazgos pueden ser el punto de partida para la construcción de propuestas que involucren equipos de trabajo afectados en el circuito de provisión en su totalidad, a fin de lograr una descentralización efectiva, en congruencia con el papel rector que le corresponde necesariamente al Programa.

OBJECTIVES: To evaluate the supply cycle of antiretroviral (ARV) drugs, overseen by the National Program to Combat Human Retroviruses, AIDS, and STDs, through its order fulfillment indicators, and to obtain input from supply chain stakeholders. METHODS: A study was carried out from AprilSeptember 2005 in the pharmacies of two hospitals in Rosario, Argentina, involving both a quantitative analysis of indicators and secondary sources and a qualitative evaluation using semistructured interviews. RESULTS: The indicators reveal the impact that interruptions in ARV supply stream from the Program (central level) have and the overstocking that takes place at the pharmacies (local level) to manage the shortages. Changes in ARV treatment account for over 50 percent of the prescriptions. Fulfillments fall short of the reference value. The interviewees shared possible strategies for overcoming the communication gaps between levels, for building-up stock, for guaranteeing availability, and for shortening waiting times; reached informal agreements to deal with the lack of policies and the shortage of staff; acknowledged the challenges facing the jurisdictions (central, intermediate, and local/community); and recognized local efforts to improve management. CONCLUSIONS: These challenges could be the starting point for building teams to work on effectively decentralizing the entire supply chain and allowing the Program to fulfill its much-needed oversight role.

Quality Standards in Provision of Facility Based HIV Care and Treatment: A Case Study from Dar Es Salaam Region; Tanzania

Objective: A cross- sectional descriptive study was conducted to assess the quality standards of health facilities providing antiretroviral treatment (ART) in Dar es Salaam from May to July 2005. Methods: All ten health facilities (both public and private) already designated by Ministry of Health (MOH) to provide ART; six of them since October 2004 and four since May 2005; were included in the study purposively . The other two not designated were randomly picked and added. A checklist with the MOH required standards was used to assess the availability of infrastructure (equipment and staff) for provision of ART; and noted the number of patient eligible; started on ART and their follow ups. Results: The study findings indicated that there were inadequate trained personnel; inadequate laboratory equipments; inadequate antiretroviral drugs and isoniazed was under utilized. There were inadequate confidential places for counseling and information system was weak. Not all the eligible patients were able to start ART and comprehensive HIV care and treatment was not provided in all the designated facilities. Conclusion: Quality standards for providing ART in eligible health facilities in Dar es Salaam varied from facility to facility with better quality standards in facilities that were designated earlier than those designated later indicating a potential for improvement in future. However fast Improvement in staff training; infrastructure; equipment and drugs supplies; health management information system is needed if we are to treat estimated more than 400;00 HIV/AIDS patients by the year 2010

Quality of antiretroviral drugs, stavudine and indinavir capsules available in the Tanzanian market

Background: The number of antiretroviral drugs (ARVs) available to HIV/AIDS patients in Tanzania is increasing due to a number of intervention programs such as PEPFAR and the Clinton Foundation. These ARVs are imported from a number of countries. However; currently there are no reports on the quality of these medicines imported into Tanzania.The sale of substandard and counterfeit drugs has been well documented particularly in developing countries. The marketing of counterfeit and substandard antiretroviral drugs has also been widely reported in Africa. It is therefore important to closely monitor the quality of ARVs marketed in Tanzania to ensure that substandard or fake products are uncovered before great harm is done to public health.Objective: To assess the quality of ARVs marketed in Tanzania.Methodology: A total of five samples of two generic drugs (stavudine and indinavir) from different manufacturers were randomly collected from various retail pharmacies.Assessment of package inserts and labels was carried out using the Tanzania Food and Drugs Authority (TFDA) specifications. The capsules were analyzed for the content of the active components using validated in-house methodsResults: All samples of Indinavir and Stavudine investigated conformed to the packaging and labeling specifications. However; all Indinavir samples were found to contain excess amount of active ingredient (112.6- 118) compared to the official limit of 95 - 105. One sample of stavudine capsules failed the dissolution test; releasing only 56instead of the specified 80of the active ingredient. Conclusion: The results of this study emphasize the need for careful monitoring of the quality of drugs to ensure their safety and efficacy