A Política de Saúde no Brasil, que inclui a Política Nacional de Medicamentos, a criação da Agência Nacional de Vigilância Sanitária (ANVISA), a promulgação da Lei de Medicamentos Genéricos, bem como a publicação das Resoluções que estabelecem os critérios técnicos para seu registro, revolucionou o mercado farmacêutico brasileiro na última década, introduzindo vários conceitos como Equivalência Farmacêutica e Terapêutica, Biodisponibilidade e Bioequivalência. Tais conceitos constituem as bases científicas para a implantação dos medicamentos genéricos, aliados à certificação de Boas Práticas de Fabricação e Controle de Qualidade (BPFs). Após cinco anos, os medicamentos genéricos representam cerca de 10% do mercado farmacêutico brasileiro em unidades com redução mínima de 35% no preço do genérico em relação ao medicamento de referência, em função de que o fabricante não necessita investir em estudos clínicos para comprovação da eficácia e segurança, garantidas pela comprovação da equivalência terapêutica com o medicamento de referência. O mercado brasileiro de genéricos é muito atrativo, pois 86% dos fármacos registrados no país não são patenteados e mais de 50% da população brasileira não tem acesso a medicamentos por problemas econômicos. Por outro lado, 70% do mercado farmacêutico brasileiro é composto por medicamentos similares, que somente em 2003 passaram a ter regulamentação técnica específica para comprovação da eficácia e segurança. Dessa forma, apesar de vasta literatura existente, justifica-se a sistematização dos aspectos técnicos e científicos que fundamentam a regulamentação técnica de biodisponibilidade relativa e bioequivalência com aplicabilidade na XXIII capacitação de recursos humanos em Biofarmacotécnica e na área regulatória no país. A análise da implantação e evolução das regulamentações técnicas, bem como, das conclusões dos estudos de bioequivalência e biodisponibilidade relativa avaliados pela ANVISA, torna-se ferramenta essencial para a compreensão dos aspectos regulatórios dos estudos de biodisponibilidade relativa e bioequivalência adotados. Considerando-se, ainda, a importância da racionalização de recursos e a necessidade de manutenção da qualidade dos medicamentos genéricos e similares no Brasil, com base na literatura científica mundial e no Banco de Dados da ANVISA, avaliou-se a viabilidade do emprego do Sistema de Classificação Biofarmacêutica (SCB), proposta elaborada por Amidon et al. (1995), para isenção da necessidade de realização de estudos de biodisponibilidade relativa/bioequivalência para o registro e pós-registro de medicamentos no Brasil. Assim sendo, concluiu-se que: a implantação de medicamentos genéricos no Brasil significou grande avanço técnico-científico para as áreas regulatória, acadêmica e industrial; a implementação e o aprimoramento da regulamentação técnica para medicamentos genéricos ocorreu devido à sua revisão contínua e publicação de quatro novas versões no período de 2.000 a 2.004; a experiência adquirida foi a base para a elaboração da regulamentação para medicamentos similares; a reprovação de estudos de bioequivalência de fármacos da Classe I do SCB é um alerta para que um estudo aprofundado das causas e da aplicação desse sistema na isenção de estudos in vivo visando o registro de medicamentos no Brasil seja realizado. / Health Policy in Brazil, which includes the National Policy on Medicines, the creation of the National Agency for Sanitary Vigilance (ANVISA), the promulgation of the Generic Medicines Law, as well as the publication of Resolutions establishing technical criteria for their registration, has revolutionized the Brazilian pharmaceutical market over the past decade introducing a number of concepts such as Pharmaceutical and Therapeutic Equivalence, Bioavailability and Bioequivalence. Such concepts have comprised the scientific basis for the implementation of generic medicines, in conjunction with the certification of Good Manufacturing and Quality Control Practices (BPFs). Five years on, generic medicines account for around 10% of the Brazilian pharmaceutical market in units, with a price cut in generics of at least 35% compared with the corresponding reference medicine, as a result of manufacturers not having to invest in clinical trials to prove efficacy and safety which are guaranteed by proof of therapeutic equivalence to the reference medicine. The Brazilian generics market is highly attractive since 86% of active principles registered in the country are not patented, and given that more than 50% of the Brazilian population does not have access to medicines for economic reasons. However, 70% of the Brazilian pharmaceutical market is made up of similar medicines, which only gained specific technical regulation for proof of efficacy and safety in 2003. Therefore, despite the vast body of literature available, a systematic approach for technical and scientific aspects underlying the technical regulation of relative bioavailability and bioequivalence is warranted, where this may also apply to both training of human resources in Biopharmaceutics and to the regulatory area in the country. Analysis of the XXVI implementation and evolution of technical regulations, along with the conclusions of ANVISA-assessed bioequivalence and relative bioavailability trials, have become an essential tool in understanding the regulatory aspects of the studies on relative bioavailability and bioequivalence adopted. Furthermore, given the continuing importance of rationalizing resources and the need to maintain the quality of generic medicines and similars in Brazil, the viability of employing the Biopharmaceutical Classification System (SCB) proposed by Amidon et al. (1995) dispensing with the need to run relative bioavailability/bioequivalence studies for the registration and post-registration of medicines in Brazil, has been assessed based on world scientific literature and ANVISAs database. Thus it was concluded that the implementation of generic medicines in Brazil has represented a major technical and scientific step forward for the regulatory, academic and industrial areas. Moreover, the implementation and refining of the technical regulations for generic medicines has taken place as a result of ongoing review and publication of four new versions between 2000 and 2004. The experience gained has provided the foundation in devising technical regulations for similar medicines. Finally, the rejection of bioequivalence studies for medicines from Class 1 SCB may serve as a warning that more in-depth studies into the root causes, and the application of this system in the absence of in-vivo studies for registration of medicines in Brazil, should be undertaken.

Orientador: Marcos Antônio de Oliveira / Coorientador: Wagner Vilegas / Resumo: O Instituto Nacional do Câncer (INCA) estima que em 2016 sejam registrados cerca de 12.600 novos casos pediátricos de câncer, sendo que 25% devem ser representados pela leucemia linfoide aguda (LLA). Todos os quimioterápicos utilizados no tratamento da LLA levam a diversos efeitos colaterais como: mutagenicidade, teratogenicidade, efeitos citotóxicos e alergias, sendo premente a necessidade da descoberta de novas drogas com efeitos indesejados reduzidos ou ausentes. Já foi demonstrado que em células tumorais a expressão de peroxidases é aumentada de modo a manter níveis adequados para o crescimento e evitar a apoptose. Em mamíferos, a peroxidase denominada de peroxirredoxina II (PrxII) aparenta ter papel fundamental na progressão e manutenção das células tumorais e e estudos recentes indicam que esta enzima possui altos níveis de expressão em células neoplásicas ao passo que sua inibição é capaz de tornar células neoplásicas mais suscetíveis ao tratamento com radioterapia ou mesmo induzir a diferenciação celular das células tumorais. Foi descoberto que o diterpenóide natural, adenantina (Adn), é capaz de inibir de forma bastante eficaz o crescimento celular in vitro e in vivo de células de LLA atuando sobre PrxII. Entretanto, não se tem informações de seus efeitos na leucemia linfoide aguda. O projeto tem como objetivos avaliar efeitos inibitórios em PrxII humana de moléculas isoladas em projetos anteriores, incluindo aquelas similares a Adn, oriundas da biota brasileira e t... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Not available / Mestre

Orientador: Jorge Fernando Brandão Pereira / Banca: Carlota de Oliveira Rangel Yagui / Banca: Marlus Chorilli / Banca: Ariela Veloso de Paula / Banca: Luis Henrique Souza Guimarães / Resumo: A L-asparaginase destaca-se como um importante biofármaco utilizado no tratamento de leucemia, além da sua utilização na indústria alimentícia. Seu alto custo de produção se deve principalmente às etapas de purificação, que correspondem em geral a mais de 70% do valor do produto final. Assim, novos processos de extração líquido-líquido, como a aplicação de Sistemas Aquosos Bifásicos (SABs), surgem como técnicas alternativas de extração/purificação mais econômica e biocompatível. Nesse sentido, este trabalho avaliou um processo alternativo para a purificação de baixa resolução da enzima L-asparaginase (ASNase) utilizando-se SABs com polímeros e sais ou líquidos iônicos (LIs). Inicialmente, foi realizado um estudo comparativo de diferentes metodologias de quantificação da atividade da ASNase comercial, a fim de compreender as interferências dos métodos em diferentes condições, e assim estabelecer um método de quantificação adequado para determinação da atividade de ASNase nos SABs. A seguir, a estabilidade da ASNase foi avaliada frente aos diferentes componentes de fases dos SABs. Dessa forma, LIs derivados de colinas e polímeros foram testados como solventes alternativos na biocatálise, e a fim de compreender o efeito do tamanho da cadeia do ânion dos LIs sob a estabilidade da enzima, foram testadas soluções aquosas contendo as colinas com os seguintes ânions: cloreto ([Ch]Cl); acetato ([Ch][Ac]); propanoato ([Ch][Pro]); butanoato ([Ch][But]) e hexanoato ([Ch][Hex]). O aumento... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: L-asparaginase (ASNase) is an important biopharmaceutical used in the treatment of leukemia, as well in industrial food processes. Its high production costs are mainly due to purification steps, in general, up to 70% of the final product value. Therefore, new liquid-liquid extraction processes, such as Aqueous Biphasic Systems (ABS), have appeared as more economical and biocompatible extraction/purification alternatives. In this work an alternative process for the purification of the enzyme L-asparaginase (ASNase) using ABS composed of polymers and salts or ionic liquids (ILs) was evaluated. In the first stage, a comparative study of different activity quantification methods of the commercial ASNase was carried out. This study intended to determine the interferences of the quantification methods and to establish the most adequate method for the quantification of ASNase activity after the extraction with different ABS. Further, the stability of the ASNase in the presence of different type and concentration of phase-forming agents, namely cholinium based-ILs ([Ch]+ -ILs) and polymers, was evaluated. Thus, in order to understand the effect of the increase of anion alkyl chain length of the ILs in the enzyme stability, aqueous solutions of [Ch]+ -ILs, with the following anions, were tested: chloride ([Ch]Cl), acetate ([Ch][Ac]), propanoate ([Ch][Pro]), butanoate ([Ch][But]) and hexanoate ([Ch][Hex]). The increase of the anion alkyl chain length had a negative effect on the enzymatic activity due to the affinity of these compounds to the protein structure. [Ch]Cl and [Ch][Ac] were selected as the best alternative solvents, because of their ASNase stability aptitude, as well enzymatic activity enhancing effect. The stability and activity of ASNase in aqueous solutions of polyethylene glycol... (Complete abstract click electronic access below) / Doutor

The emerging class of biologic drugs, including proteins, peptides, and gene therapies, are widely administered by injection, despite potential systemic side effects. Rational design of targeted carriers that can be delivered non-invasively, with reduced side effects, is essential for the success of these therapies, as well as for the improvement of patient compliance and quality of life. One potential approach is to take advantage of specific physiological cues, such as enzymes, which would trigger drug release from a drug carrier. Enzymatic cleavage is highly specific and could be tailored for certain diseased tissues where specific enzymes are up regulated. Enzymatically-degradable hydrogels, which incorporate an enzyme- cleavable peptide into the network structure, have been extensively reported for releasing drugs for tissue engineering applications. These studies showed that a rapid response and corresponding drug release occurs upon enzyme exposure, whereas minimal degradation occurs without enzyme. Recently, Michael addition reactions have been developed for the synthesis of such enzymatically-degradable hydrogels. Michael addition reactions occur under mild physiological conditions, making them ideally suited for polymerizing hydrogels with encapsulated biologic drugs without affecting its bioactivity, as in traditional polymerization and particle synthesis. The focus of my research was to create enzymatically-degradable hydrogel microparticles, using Michael addition chemistry, to evaluate for use as an inhalable, disease-responsive delivery system for biologic drugs and nanoparticles. In this dissertation, I utilize bioconjugation and Michael addition chemistries in the design and development of enzymatically-degradable hydrogels, which may be tailored to a multitude of disease applications. I then introduce a new method of hydrogel microparticle, or microgel, synthesis known as the Michael Addition During Emulsion (MADE) method. These microgel carriers were evaluated in vitro, and found to exhibit triggered release of encapsulated biologic drugs in response to enzyme, no significant cytotoxic effects, and the ability the avoid rapid clearance by macrophages. Lastly, in vivo studies in mice were conducted, and microgels were found to exhibit successful delivery to the deep lung, as well as prolonged pulmonary retention after intratracheal aerosol delivery. In conclusion, a new class of enzymatically-degradable microgels were successfully developed and characterized as a versatile and promising new system for pulmonary, disease-responsive delivery of biologic drugs. / text

Recently, the portfolio of compounds approved for inhalation therapy has expanded rapidly for lung disease therapies. The rationale for this delivery approach includes a more targeted and localized delivery to the diseased site with reduced systemic exposure, potentially leading to decreased adverse side effects. We have proposed that brittle matrix powders prepared by thin film freezing (TFF) are a suitable platform for pulmonary drug delivery which can achieve high lung concentrations while limit the corresponding systemic levels associated with toxicity, and enhanced physicochemical and aerodynamic properties can be obtained by varying TFF processing parameters. In Chapter 2, the in vitro and in vivo performance of an amorphous formulation prepared by TFF and a crystalline micronized formulation produced by milling was compared for Tacrolimus (TAC). TFF processed matrix powders was capable of achieving deep lung delivery due to its low density, highly porous and brittle characteristics. When emitted from a Miat® monodose inhaler, TFF processed TAC formulations exhibited a fine particle fraction (FPF) of 83.3% and a mass median aerodynamic diameter (MMAD) of 2.26 µm. Single dose 24-h pharmacokinetic studies in rats demonstrated that the TAC formulation prepared by TFF exhibited higher pulmonary bioavailability with a prolonged retention time in the lung, possibly due to decreased clearance (e.g., macrophage phagocytosis), compared to the micronized TAC formulation. Additionally, TFF formulation generated a lower systemic TAC concentration with smaller variability than the micronized formulation following inhalation, potentially leading to reduced side effects related to the drug in systemic circulation. Chapter 3 investigated the impact of processing parameters in the TFF process on the physicochemical and aerodynamic properties of the resulting formulations. All of these enhanced powder properties resulted from higher freezing rate contributed to a better aerodynamic performance of the obtaining formulations. Moreover, a decreasing trend of FPF was observed for these TFF powders when the initial solid concentrations increased. The variation of the freezing rate and initial solid loading in the TFF process enabled the production of formulations with enhanced physicochemical properties and improved aerodynamic performance. / text

Submitted by Rafael Santana (rafael.silvasantana@ufpe.br) on 2017-10-31T18:48:15Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Tese_Dout.JoseValdilanioVirgulinoProcopio.pdf: 8702364 bytes, checksum: fc9076819663d6de5dd78173e2cebcbf (MD5) / Made available in DSpace on 2017-10-31T18:48:15Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Tese_Dout.JoseValdilanioVirgulinoProcopio.pdf: 8702364 bytes, checksum: fc9076819663d6de5dd78173e2cebcbf (MD5) Previous issue date: 2015-02-27 / FACEPE / Há vários relatos científicos de modificações in vitro, nas características de Insumos farmacêuticos ativos (IFAs) em formulações contendo celulose microcristalina (CMC), porém há escassez de estudos para avaliar sua influência in vivo. Este trabalho teve como objetivo avaliar a influência da celulose microcristalina de diferentes origens e tamanhos de partícula na estabilidade, cinética de liberação in vitro e correlacionar com estudos in vivo utilizando IFAs de diferentes classes biofarmacêuticas. Foram utilizados lotes de CMC de dois diferentes fabricantes (A e B), com diferentes tamanhos CMC101 e CMC102, três lotes dos IFAs sinvastatina (Sinv) e fluconazol (Fluc) e um lote do ibuprofeno (Ibup). Foram obtidos dezesseis lotes de comprimidos dos IFAs com as celuloses. As técnicas analíticas: difração de raio X, análise térmica, microscopia eletrônica de varredura, cromatografia líquida de alta eficiência e dissolução permitiram a caracterização dos IFAs, CMCs e comprimidos. Estudos de biodisponibilidade foram realizados utilizando coelhos Nova Zelandia como modelo, após avaliação e aprovação ética, Certificado n° 0308/11, e validação dos métodos bioanalíticos. As CMCs apresentaram diferenças nas características de degradação térmica, nas análises microscópicas e de cristalinidade em função da origem e/ou do tamanho de partícula. A Sinvastatina mostrou diferenças entre os lotes no comportamento de fusão, decomposição térmica e dissolução intrínseca. Os comprimidos contendo sinvastatina apresentaram liberação conforme o modelo matemático de El-Yazigi e houve diferenças nas características de estabilidade e dissolução em função do tipo de celulose utilizada na sua produção. Foi estabelecida correlação direta entre a quantidade liberada na dissolução e os dados de estabilidade térmica para todos os comprimidos contendo a Sinv com todas as CMCs, exceto para a CMC101B, que apresentou cristalinidade diferente das demais. O Fluconazol não apresentou diferenças significativas entre os lotes na dissolução, fusão e decomposição térmica. Os comprimidos contendo Fluc e CMC101 dos diferentes fabricantes apresentaram liberação conforme o modelo matemático de El-Yazigi, os perfis de dissolução em água foram semelhantes, no entanto diferiram in vivo, de modo que não foi estabelecida correlação in vitro/in vivo, sendo o modelo in vivo mais eficiente no sentido de detectar a diferença existente entre as formulações. O ibuprofeno apresentou perda de massa em uma única etapa na termogravimétria e através do DSC-fotovisual e pirólise acoplada a espectrometria de massa foi possível confirmar que ela ocorreu por vaporização. Os comprimidos contendo Ibuprofeno e CMC101 dos diferentes fabricantes não apresentaram diferenças entre os perfis de dissolução utilizando tampão fosfato pH 7,2. Utilizando água, como meio de dissolução, a liberação ocorreu conforme o modelo matemático de Higuchi havendo diferença na liberação em função da origem da CMC101 utilizada. Foi estabelecida correlação in vitro/in vivo utilizando água como meio de dissolução. Houve diferença na liberação e absorção do ibuprofeno, a partir dos comprimidos, em função da celulose microcristalina utilizada para sua produção. Esses resultados mostram a importância e necessidade de estudos mais amplos que os farmacopéicos, incluindo estudos de correlação in vitro-in vivo, na avaliação da influência dos excipientes, em função da origem, na cinética de liberação dos comprimidos e biodisponibilidade durante a qualificação de fornecedores. / There are several scientific reports of in vitro changes in the characteristics of various active pharmaceutical ingredients (APIs) in Formulaçãos containing microcrystalline cellulose (MCC), but there are few studies to evaluate its influence in vivo. This study aimed to evaluate the influence of microcrystalline cellulose from different Fontes and particle size to stability, in vitro release kinetics and correlate with in vivo studies using APIs of different biopharmaceutical classes. Were used two different lots of MCC by manufacturers (A and B) with different sizes CMC101 and CMC102, three lots of APIs simvastatin (Sinv) and fluconazole (Fluc) and one lot of ibuprofen (Ibup). Sixteen batches of tablets were obtained by direct compression of APIs with cellulose. The analytical techniques: X-ray diffraction, thermal analysis, scanning electron microscopy, high performance liquid chromatography and dissolution efficiency allowed the characterization of APIs, CMCs and tablets. Bioavailability studies were conducted using rabbits New Zealand as a model, after analysis and approval Certificate No. 0308/11, and validation of bioanalytical methods. The MCCs showed different characteristics of thermal degradation, the microscopic analysis and crystallinity according to the origin and / or size. The Simvastatin showed differences between batches behavior during melting, thermal decomposition and intrinsic dissolution. Tablets containing simvastatin showed release as a mathematical model El-Yazigi were differences in the stability and dissolution characteristics depending on the type of MCC used in its production, was established a direct correlation between the amount released in the dissolution and stability data Thermal for all Sinv tablets containing CMC with all except for the CMC-101B, which has different crystallinity characteristics. The Fluconazole no showed significant differences between the lots in the dissolution, melting and thermal decomposition. Tablets containing Fluc and CMC101 from different manufacturers presented equal release (El-Yazigi) and dissolution profiles in water however differed in vivo, correlation of data in vivo / in vitro is not established. The in vivo model was more efficient in order to detect the difference between the formulations containing fluconazole. Ibuprofen showed weight loss in one step by the thermogravimetry and DSC-fotovisual and pyrolysis-mass spectrometry it was that it is vaporization. Tablets containing Ibup and CMC101 from different manufacturers showed no differences between the dissolution profiles using pH 7.2 phosphate buffer. Using water as the dissolution medium, the release occurred as the mathematical model of Higuchi and showed difference in the release as to the origin of CMC101, correlation of data in vitro / in vivo is established and showed differences in absorption. These results show the need for studies beyond pharmacopoeial methods, including correlation studies in vitro-in vivo, at the evaluation of the excipients, depending on the origin, the release kinetics of tablets and bioavailability during qualifying suppliers.

A absorção oral de um fármaco é fundamentalmente dependente da solubilidade aquosa e da permeabilidade gastrintestinal. Estes são fatores determinantes da biodisponibilidade e, consequentemente, da eficácia clínica de um medicamento. O Sistema de Classificação Biofarmacêutica (SCB), fundamentado nas propriedades de solubilidade e permeabilidade, consolidou-se nos últimos anos como ferramenta de auxílio na predição da biodisponibilidade de fármacos e tem sido empregado no desenvolvimento de formas farmacêuticas, contendo novos fármacos ou não, bem como no registro de medicamentos genéricos. O emprego do SCB para a isenção dos estudos de biodisponibilidade relativa/bioequivalência para algumas classes de fármacos vem sendo adotado e discutido, uma vez que os ensaios de biodisponibilidade apresentam limitações técnicas, econômicas e éticas. Assim, nos últimos anos, Agências Regulatórias têm utilizado o SCB para permitir que testes de dissolução in vitro sejam usados para estabelecer bioequivalência no caso de fármacos altamente solúveis e altamente permeáveis. O presente trabalho tem como objetivos revisar e reunir a literatura relacionada ao SCB com vistas a discutir a possibilidade de isenção dos estudos de biodisponibilidade relativa / bioequivalência para os medicamentos. Com esta proposta, foram pesquisadas as bases de dados Pubmed, Medline, Legislações Brasileiras indexadas no Visalegis e Legislação Internacional. Buscou-se a literatura pertinente publicada no período entre 1980 e o primeiro semestre de 2009. Desde a introdução do SCB existe uma relutância na aplicação das bioisenções para o registro de genéricos uma vez que as indústrias farmacêuticas não querem arriscar uma rejeição à sua solicitação nos países onde esse sistema ainda não é aceito, principalmente devido à falta de harmonização da legislação global. No Brasil, o SCB não é aceito para isenção de estudos de biodisponibilidade relativa/bioequivalência, pois os dados de permeabilidade são escassos na literatura científica para a grande maioria dos fármacos e ainda não existem protocolos validados para os estudos de permeabilidade. Além disto, o país ainda não possui um sistema de registro e controle de qualidade de princípios ativos e excipientes, ou seja, até o momento, não há regulamentação técnica para registro de matérias-primas de produtos farmacêuticos e cosméticos, ao contrário do que existe nos Estados Unidos. Para uma melhor aplicabilidade do SCB nas bioisenções as seguintes questões devem ser destacadas: continuidade do suporte científico para assegurar bioisenções para fármacos da Classe III; suporte científico para as metodologias de determinação de permeabilidade, com o objetivo de determinar a classificação biofarmacêutica dos fármacos; discutir a aplicação da Classificação Biofarmacêutica na fase de pesquisa e desenvolvimento de novas moléculas. / The oral absorption of a drug is fundamentally dependent on the aqueous solubility and gastrointestinal permeability. Those are determinant factors of the bioavailability of a drug and of the clinical efficacy of a pharmaceutical product. The Biopharmaceutics Classification System (BCS) is based on the properties of solubility and permeability and has been developed as a tool to predict bioavailability of drugs. BCS has also been used in the development of new dosage forms, including new molecules or not, as well as in the registration of generic drugs. The use of BCS as a \"waiver\" of in vivo bioavailability and bioequivalence studies for some drug classes has been discussed, since bioavailability studies represent technical, economical and ethical limitations. Therefore, in the last years the Regulatory Agencies have used BCS to allow that in vitro dissolution tests be used to establish bioequivalence in the case of highly soluble and highly permeable drugs. The present study has the objective to review the literature related to BCS, focusing in the discussion of biowaivers. The research was conducted using the following databases: Pubmed, Medline, Brazilian legislation indexed in the ANVISA website (VISALEGIS) and international legislation. The research period was between 1980 and the first semester of 2009. Since the introduction of BCS there is reluctance in the application of a biowaiver because the pharmaceutical companies do not want to risk a rejection of their biowaiver request in the countries where this system has not been established yet and also due to the lack of global legislation harmonization. In Brazil the BCS is not accepted for waiving bioequivalence studies, since permeability data are not very common in the scientific literature, for the great majority of drugs. Besides, the country does not have a regulatory framework for the registration of active pharmaceutical ingredients and raw materials, as it happens in the United States. In order to give a better applicability of BCS in biowaiver requests, the following questions must be pointed out: continuity of scientific support to assure biowaivers for Class III drugs; scientific support for permeability methodologies determination; discuss the applicability of BCS in early development phase studies for new molecular entities.

Conventional solid dosage forms often lead to fluctuations which exceed the maximum safe therapeutic level and/or decline below the minimum effective level. It is recognised that many drugs for chronic administration should be administered on a schedule that maintains plasma drug concentration within the therapeutic window. Research in controlled release dosage forms aims at designing a system with a zero-order input (eg, ideally to deliver 8.33% of the dose per hour over a 12 hour duration), producing steady state plasma drug levels. Oral dministration of drugs prepared as a controlled release formulation is extremely popular, and has attracted the attention of pharmaceutical scientists during the last decade. This has been due to the simultaneous convergence of various factors (eg, discovery of novel polymers and devices, better understanding of formulation and physiological constraints, expiration of existing patents, prohibitive cost of developing new drug entities), involved in the development of these delivery systems. Controlled release oral products can be formulated as single or multiple unit dosage forms and the relative merits of multiple unit forms with their own rate controlling systems are well established. This work describes the development of a relatively inexpensive multiple-unit capsule dosage form of theophylline containing coated mini-tablets for drug delivery throughout the gastrointestinal tract. Preformulation studies on theophylline anhydrous included solubility and dissolution rate determinations. Techniques including X-ray powder diffraction, differential scanning colorimetry and infrared spectroscopy provided no evidence of true polymorphism after recrystallisation from various solvents. However, scanning electron micrographs showed the effects of solvent polarity and cooling rate on the size and shape of recrystallised particles. Theophylline granules were manufactured by using various binders and were film coated by fluidised bed technology with various proportions of ethylcellulose, containing varying amounts of PEG 1540. In vitro release rates were dependent upon coating thickness and the proportion of PEG, which, being water soluble, created pores in the coating during dissolution studies as observed by a scanning electron microscope. However, substantial proportions of the drug remained unreleased from the granules. In order to overcome the problems of drug retention, plain granules were used and theophylline mini-tablets (3 mm diameter, weighing 15 - 20 mg) were manufactured and film coated with various Eudragits ® and other polymeric mixtures (soluble and insoluble). In vitro dissolution profiles from samples enclosed in hard gelatin capsules were determined using the USPXXI paddle apparatus in test media at pH 1.2 (HCI), pH 5.4 and 7.4 (phosphate buffers) at 37'C. Monitoring of in vitro theophylline release over 12 h, under identical hydrodynamic conditions, showed that the dissolution rate at pH 1.2 is substantially greater (95% of total drug content released in < 10 h) than that in phosphate buffers. The maximum release after 12 h was approximately 20 and 30% of total drug content of the tablet at pH 5.4 and 7.4, respectively. However, in vivo bioavailability after oral administration of tablets to rabbits corresponded to over 95% of total drug, compared with the same dose administered intravenously. The retarded drug release during in vitro dissolution in phosphate buffer was attributed to a possible interaction of phosphate ions with theophylline molecules at the tablet core-coat interface. These findings indicate that both rate and extent of theophylline release from the slow release coated mini-tablets are highly sensitive to phosphate buffers. The data also emphasise the usefulness of an animal model for assessment of in vivo drug release and subsequent absorption during the development of modified release dosage forms. Mini-tablets were subjected to isothermal and cyclic stresses to reach conditions for up to 6 months at different temperatures and relative humidity. The film integrity was maintained but ageing of the coating occurred which impeded dissolution. Reduced drug release was temperature related while the effect of relative humidi% was insignific~t. Encapsulated mini-tablets (uncoated and coated with Eudragit RL and RS 2% w/w) equivalent to a 300 mg dose, were evaluated both in vitro and in vivo using beagle dogs. The pharmacokinetic parameters from single and multiple dose studies showed several advantages over Theo-Dur® 300 mg tablets. Precise dosage titration is possible by careful adjustment of the number of encapsulated mini-tablets. This multiple unit mini-tablet delivery system will allow for greater flexibility in dosage adjustment compared to the currently available preparations, allowing individualised fine dose titration in those patients requiring therapeutic drug monitoring. The developmentof the multiple unit mini-tablet formulation appears to provide an optimal dosage form with maximum flexibility in respect of dose, duration range and ease of production.

O objetivo do presente trabalho foi avaliar o impacto de diferentes variáveis no ensaio de dissolução intrínseca de metronidazol. Inicialmente, as amostras, com diferentes graus de micronização, foram submetidas à caracterização físico-química, sendo realizados ensaios de solubilidade, tamanho de partícula, análise térmica (DSC/ TG), infravermelho por transformada de Fourier (FTIR), difratometria de raios X (DRX), análise de área superficial pelo método BET, microscopia óptica, densidade verdadeira e densidade compactada. Na sequência, foram realizados os ensaios de dissolução intrínseca segundo um planejamento experimental do tipo fatorial fracionado, sendo cada fator avaliado em três níveis. Para o delineamento, utilizou-se o programa Statistica 8.0. e os fatores estudados foram: velocidade de rotação, pressão utilizada na formação do compactado do fármaco, meio de dissolução e grau de micronização. Os resultados mostraram alteração nas propriedades reológicas do material conforme o aumento do grau de micronização, enquanto as demais propriedades não foram afetadas. Entre os fatores estudados no delineamento, a velocidade de rotação e o meio de dissolução, foram aqueles que exerceram influência significativa na dissolução intrínseca do metronidazol. Embora a solubilidade do fármaco não sofra influência do tamanho de partícula, valores superiores foram observados em HCl 0,1 M, meio em que também foram obtidas as mais elevadas velocidades de dissolução intrínseca (VDIs). / The purpose of this study is to evaluate the impact of different variables in the intrinsic dissolution test of metronidazol. Initially, the samples, with different levels of micronization, underwent physicochemical characterization, whereby they were tested for solubility, particle size, thermal analysis (DSC/TG), Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (DRX), surface area analysis by the BET method, optical microscopy, true density and tapped density. Then, intrinsic dissolution tests were carried out according to fractional factorial experimental planning, with each factor being evaluated on three levels. The Statistica 8.0 software program was used for design, and the factors studied were: rotational velocity, pressure used in the formation of the compressed drug, dissolution medium and level of micronization. The results indicated alterations in the rheological properties of the material, as the level of micronization increased, while the remaining properties were unaffected. Among the factors studied in the design, the rotation speed and the dissolution medium were the factors that exercised the most significant influence on the intrinsic dissolution of metronidazol. Although the solubility of the drug is not influenced by particle size, higher values were observed in HCl 0.1 M, the medium in which the highest intrinsic dissolution rates (IDRs) were also obtained.

Metastasis is the primary cause of mortality in women with breast cancer. Recently, elevated serum levels of a glycoprotein known as chitinase-3 likeprotein- 1 (CHI3L1) has been correlated with poor prognosis and shorter survival of patients with cancer and inflammatory diseases. The biological and physiological functions of CHI3L1 in tumor progression have not yet been elucidated. In this document, we describe the role of CHI3L1 in tumor growth and metastasis and its relationship with inflammation. Using well-established models of breast cancer, we show that CHI3L1 is increased in the serum of tumor bearing mice. We found that CHI3L1 levels are increased at both the “pre-metastatic” and “metastatic stage” and that tumor cells, splenic, alveolar and interstitial macrophages; and myeloid derived population produce CHI3L1. Furthermore, we demonstrated that CHI3L1 has an inhibitory role on the expression of interferon-gamma (IFN γ) by T cells, while enhancing the production of pro-inflammatory mediators by macrophages such as Cchemokine ligand 2 (CCL2/MCP-1), Chemokine CX motif ligand 2 (CXCL2/IL-8) and matrix metalloproteinase-9 (MMP-9), all of which promote tumor growth and metastasis. We demonstrated that in vivo treatment of tumor-bearing mice with chitin microparticles, a TH1 adjuvant and a substrate for CHI3L1, promoted immune effector functions with increased production of IFN-γ but decreased CCL2/MCP-1, CXCL2/IL-8 and MMP-9 expression by splenic and pulmonary macrophages. Significantly, in vivo administration of chitin microparticles decreased tumor growth and pulmonary metastasis in mammary tumor bearing mice. These results suggest that CHI3L1 may play a role in tumor progression. Inflammation plays a pivotal role during tumor progression and metastasis by promoting the production of pro-inflammatory molecules such as CHI3L1. However, little is known about how CHI3L1 expression can affect secondary sites to enhance metastasis. In these studies, we demonstrated that CHI3L1 alters the cellular composition and inflammatory mediators that aid in the establishment of a metastatic niche for the support of infiltrating tumor cells leading to accelerated tumor progression. Since previous studies showed that CHI3L1 modulates inflammation, we determined the role of CHI3L1 in the context of pre-existing inflammation and metastasis. We found that CHI3L1 deficient mice with preexisting inflammation had decreased pro-inflammatory mediators, and significant reduction in tumor volume and metastasis compared to wild type controls. Preexisting inflammation and CHI3L1 may be driving the establishment of a premetastatic milieu in the lungs and aiding in the establishment of metastasis. Understanding the role of CHI3L1 in inflammation during tumor progression could result in the design of targeted therapies for breast cancer patients. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection