A venlafaxina é um fármaco usado no tratamento da depressão e dos transtornos de ansiedade generalizada. É disponível na clínica na forma de mistura racêmica dos enantiômeros S-(+) e R-(-) em formulação de liberação controlada. O enantiômero S-(+) inibe a recaptação da serotonina, enquanto o enantiômero R-(-) inibe a recaptação da serotonina e da norepinefrina. A venlafaxina é biotransformada pelo CYP2D6 e CYP2C19 em seu principal metabólito, O-desmetilvenlafaxina, o qual apresenta atividade farmacológica semelhante à venlafaxina. Outros metabólitos da venlafaxina, dependentes do CYP3A4, incluem a N-desmetilvenlafaxina e a N,O-di-desmetilvenlafaxina. A absorção e a distribuição da venlafaxina são moduladas pela ação da glicoproteina-P. O nifedipino, um fármaco da classe dos inibidores dos canais de cálcio, é descrito como inibidor da glicoproteina-P. O presente estudo investiga a influência do nifedipino na disposição cinética e no metabolismo da venlafaxina em voluntários sadios caracterizados como portadores de atividade normal do CYP3A (omeprazol como fármaco marcador) e fenotipados como metabolizadores rápidos do CYP2C19 (omeprazol como fármaco marcador) e do CYP2D6 (metoprolol como fármaco marcador). Os voluntários investigados receberam, em estudo cruzado e randomizado, dose única oral de 150 mg de venlafaxina racêmica (Fase 1) e 40 mg de nifedipino associada com dose única oral de 150 mg de venlafaxina racêmica (Fase 2). Foram coletadas amostras seriadas de sangue até 72 horas após a administração dos fármacos para o estudo farmacocinético. As concentrações plasmáticas dos enantiômeros da venlafaxina e de seus metabólitos foram determinadas por LC-MS/MS utilizando a coluna Chirobiotic V com fase móvel constituída de mistura de metanol: solução aquosa de acetato de amônio 15 mmol/L pH 6,0 (80:20, v/v). A farmacocinética da venlafaxina mostrou-se enantiosseletiva com acúmulo plasmático (AUC 526,0 vs 195,7 ng.h/mL) e menores valores de clearance (Cl/f 142,67 vs 408,01 L/h) para o enantiômero S-(+). A disposição cinética do metabólito ativo O-desmetilvenlafaxina apresentou enantiosseletividade apenas no parâmetro concentração plasmática máxima com observação de maiores valores para o enantiômero R-(-) (Cmax 69,33 vs 56,94 ng/mL). A disposição cinética da N,O-di-desmetilvenlafaxina também mostrou-se enantiosseletiva apenas para o parâmetro concentração plasmática máxima, mas com observação de maiores valores para o enantiômero S-(+) (Cmax 7,08 vs 4,61 ng/mL). A administração de dose única oral de 40 mg de nifedipino não alterou a farmacocinética de ambos os enantiômeros da venlafaxina e de seus metabólitos O-desmetilvenlafaxina e N,O-di-desmetilvenlafaxina, seja utilizando teste estatístico não paramétrico (teste de Wilcoxon para dados pareados, p < 0,05), seja avaliando o IC 90% das razões das médias geométricas de AUC e Cmax (Fase 2/Fase 1). Os dados obtidos evidenciam que o nifedipino na dose de 40 mg não age como um inibidor da P-gp / Venlafaxine is a drug used to treat depression and generalized anxiety disorders. It is available in clinical practice in the form of a racemic mixture of S-(+) and R-(-) enantiomers, in controlled release formulation. The S-(+) enantiomer inhibits the reuptake of serotonin, while the R-(-) enantiomer inhibits the reuptake of both serotonin and norepinephrine. Venlafaxine is biotransformed by CYP2D6 and CYP2C19 in its major metabolite, O-desmethylvenlafaxine, which has similar pharmacological activity when compared to venlafaxine. Other metabolites of venlafaxine, dependent of CYP3A4, include N-desmethylvenlafaxine and N, O-di-desmethylvenlafaxine. The absorption and distribution of venlafaxine are modulated by the action of P-glycoprotein. Nifedipine, a calcium channel blocker drug, is described as an inhibitor of P-glycoprotein. The present study investigates the influence of nifedipine on the kinetic disposition of venlafaxine enantiomers and its metabolites in healthy volunteers characterized as having normal activity of CYP3A (omeprazole as a probe drug) and phenotyped as rapid metabolizers of CYP2C19 (omeprazole as a probe drug) and CYP2D6 (metoprolol as a probe drug). The enrolled volunteers received, in a randomized, two-way study, a single 150 mg oral dose of racemic venlafaxine (Phase 1) and 40 mg oral dose of nifedipine associated with a single 150 mg oral dose of racemic venlafaxine (Phase 2). Serial blood samples were collected until 72 hours after drug administration to the pharmacokinetic study. Plasma concentrations of venlafaxine enantiomers and its metabolites were determined by LC-MS/MS using a Chirobiotic V column and a mobile phase constituted of methanol: aqueous 15 mmol/L ammonium acetate solution pH 6.0 (80:20, v/v). The venlafaxine pharmacokinetics is enantioselective with plasma accumulation (AUC 526.0 vs 195.7 ng h/mL) and lower clearance values (CL/f 142.67 vs 408.01 L/h) for the S-(+) enantiomer. The kinetic disposition of the active metabolite O-desmethylvenlafaxine exhibits enantioselectivity only in the maximum plasma concentration parameter with higher values for the R-(-) enantiomer (Cmax 69.33 vs 56.94 ng/mL). The kinetic disposition of N,O-di-desmethylvenlafaxine is also enantioselective only for the maximum plasma concentration parameter, but with higher values for the S-(+) enantiomer (Cmax 7.08 vs 4.61 ng/ml). Administration of a 40 mg single oral dose of nifedipine do not alter the pharmacokinetics of both enantiomers of venlafaxine and its metabolites O-desmethylvenlafaxine and N,O-di-desmethylvenlafaxine, using non-parametric statistical test (Wilcoxon test for paired data, p <0.05), or evaluating the 90% CI of the AUC and Cmax geometric mean ratios (Phase 2/Phase 1). The obtained data show that nifedipine in a 40 mg oral dose does not act as a P-gp inhibitor.

Orientadores: Cesar Costapinto Santana, Maria Helena Andrade Santana / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-23T22:47:03Z (GMT). No. of bitstreams: 1 Guimaraes_CarlaAiolfi_D.pdf: 2218359 bytes, checksum: 4601d72639c63e8a3a04c5b06354c5bf (MD5) Previous issue date: 2013 / Resumo: O carcinoma adrenocortical (CAC) é uma neoplasia rara e maligna que surge no córtex das glândulas adrenais. A terapia mais utilizada é o tratamento com mitotano, um derivado do inseticida, que possui uma baixa solubilidade aquosa e permeabilidade intestinal. O mitotano é administrado como uma mistura racêmica composto de dois enantiômeros: R-(+) - o,p'-DDD e S-(-) - o,p'-DDD. Os carreadores lipídicos nanoestruturados (NLCs) são utilizados como suporte para a encapsulação de agentes ativos lipofílicos como é o caso do mitotano, ajudando a aumentar sua solubilidade. O objetivo deste trabalho foi caracterizar os enantiômeros e preparar NLCs encapsulando a forma enantiomérica (S) - (-) - o,p'-DDD, pela técnica de homogeneização de alta pressão a quente, caracterizar a formulação, estudar sua estabilidade, avaliar a permeação intestinal ex vivo pelo modelo do saco intestinal invertido e a retenção do enatiômero (S) - (-)- o,p'-DDD nas NLCs expostas em diferentes valores de pH in vitro. Foi utilizado NLCs contendo mitotano racêmico como controle. NLCs encapsulando (S) - (-) - o,p'-DDD tiveram diâmetro médio 95,36 nm, polidispersidade 0,288 e potencial zeta baixo -20,9 mV com uma eficiência de encapsulação alta. Os resultados de absorção intestinal ex vivo indicaram que a absorção das NLCs encapsulando o (S) - (-) - o, p'-DDD foi maior em comparação com o (S) - (-) - o, p'-DDD na forma livre e com a NLCs encapsulando o mitotano racêmico. No entanto, o teste com pH mostrou que cerca de 70% do (S) - (-) - o, p'-DDD encapsulado ficou retido nas NLCs durante 3h. Estes resultados indicaram que a formulação de NLCs produzida foi eficiente como carreador da forma S(-)-o,p'-DDD, podendo ser explorada como uma possível formulação alternativa para o tratamento do CAC. / Abstract: The adrenocortical carcinoma (ACC) is a rare malignant neoplasm that appears in the adrenal cortex. The main pharmacological choice is mitotane, a insecticide derivative, which has low aqueous solubility and low intestinal permeability. Mitotane is administered as a racemic mixture composed of two enantiomers R-(+) - o, p'-DDD and S-(-) - o, p'-DDD. The nanostructured lipid carriers (NLCs) are used as support for the encapsulation of lipophilic actives such as mitotane to improve their solubility. The aim of this work was to characterize the enantiomers and prepare the NLCs encapsulating the enantiomeric form (S) - (-) - o, p'-DDD by high pressure homogenization method and than characterize, study the stability, evaluate the ex vivo intestinal permeation by gut sac model and the retention of enantiomer (S) - (-) - o, p'-DDD in the NLCs in different pH values in vitro. NLCs encapsulating racemic mitotane was used as a control. The mean diameter and polydispersity index of NLCs encapsulating (S) - (-) - o, p'-DDD was 95.36 nm and 0.288 with a low zeta potential -20.9 mV and Higher entrapment efficiency. The ex vivo intestinal absorption results indicated that the absorption of NLCs loading(S)-(-)- o,p'-DDD was greatly improved compared to micronized free powder and when compared to NLCs loading mitotano racemic. However, the pH test showed that about 70% of (S) - (-) - o, p'-DDD encapsulated was retained in the NLCs for 3h. These results indicated that the NLC produced was effective as S (-)-o, p'-DDD carrier and could potentially be exploited as a possible alternative formulation for the ACC treatment. / Doutorado / Desenvolvimento de Processos Biotecnologicos / Doutora em Engenharia Quimica

Porous cellulose nitrate membranes were impregnated with 8CB and PCH5 LCs (liquid crystals) and separations of solutes dissolved in aqueous phases were performed while monitoring solute concentration via UV-VIS spectrometry. The diffusing organic solutes, which consist of one aromatic ring and various functional groups, were selected to exclude molecular size effects on the diffusion and sorption. We studied the effects on solute transport of solute intra-molecular hydrogen bonding and solute/LC intermolecular hydrogen bonding. Hydrogen-bonding effects are a significant factor in the permeation selectivity of positional isomers. The reduction of available hydrogen-bond donors in aromatic ortho-isomers due to intramolecular H-bonding resulted in significant differences in the diffusion relative to the para-isomers which possessed more available H-bond donors. Solutes possessing multiple H-bonding interactions experienced a higher barrier to diffusion and, consequently, lower diffusivities. Diffusing solutes with a single available H-bond donor exhibited faster diffusion than solutes without H-bond donors. PCH5 embedded membranes showed higher solubility and diffusivity than the 8CB embedded membranes due to less dense molecular packing in PCH5 resulting from the bent cyclohexyl ring. The PCH5 LC membranes demonstrated enhanced permeation selectivity for hydroxybenzoic acid and aminophenol isomers primarily due to increased sorption selectivity. Shape selective absorption of rod-like para-isomers in the nematic phase was observed in both 8CB and PCH5 LCs. A nonchiral based HPLC-CD (High Performance Liquid Chromatography-CD) system was developed for the characterization of enantioselective separations. An enantioselective cholesteric liquid crystal membrane was fabricated and evaluated using the nonchiral HPLC-CD system. The cholesteric LC membrane showed enantioselectivity in the cholesteric phase where activation energies of permeation for 1-phenylethanol enantiomers were significantly increased due to the increased interactions between enantiomer and LC phase. The enantioselectivity increased with decreasing pore size of the membrane and increasing chiral dopant compositions. The selectivity decreases when there are no hydrogen bonding interactions between enantiomer and chiral dopant. / Ph. D.

No description available.

Thesis submitted in fulfilment of the requirements for the degree Magister Technologiae: Chemistry in the Faculty of Applied Science at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY 2012 / Chirality is very important to the pharmaceutical industry as enantiomers have the same macroproperties except for their optical and pharmacological activity. Industrial research has thus focused to find the most effective resolution technique. However, our aim was to obtain more information regarding the discrimination process. In this project the structures of the hydrates of di-quininium L-malate, (2QUIN+)(L-MA2-)•2H2O and the di-quininium D-malate, (2QUIN+)(D-MA2-)•2H2O have been investigated. (-)-Quinine (QUIN) did not show selectivity between the D and L malic acid and the structure of (2QUIN+)(DL-MA2-)•2H2O was obtained. Effect of solvents was demonstrated in the study and the structure of (QUIN+)(D-MA-)•H2O) was reported. The relationship between C-O bonds of the carboxylate and carboxylic moieties and ÄpKa was explored in salt and co-crystal formation. Kinetics of absorption was conducted for the reaction of (+)-deoxycholic acid (DCA) with n-propylamine and DCA with racemic sec-butylamine. The rate constants of the reactions were determined. Kinetics of desolvation was performed on the powder samples of mixtures of DCA and sec-butylamine and DCA with di-n-butylamine. Non-isothermal methods were used where a series of TG analyses was carried out at different heating rates (2, 4, 10, 32 K min-1). The structures of DCA with n-propylamine and di-n-butylamine were elucidated. The selectivity of DCA was investigated. The host compound was found to be able to successfully resolve racemic sec-butylamine (2-BUAM) and 2-amino-3-methylbutane (MeBUAM). The structures of DCA with enantiomers of these guests are reported in the study. The structures of R-BUAM and S-BUAM were solved in different space groups while R-MeBUAM and S-MeBUAM crystallized in the same space group.

Submitted in fulfillment of the requirements for the Doctor of Philosophy degree in Chemistry, Durban University of Technology, Durban, South Africa, 2016. / In drug discovery and development projects, metabolism of new chemical entities (NCEs) is a major contributing factor for the withdrawal of drug candidates, a major concern for other chemical industries where chemical-biological interactions are involved. NCEs interact with a target macro-molecule to stimulate a pharmacological or toxic response, known as pharmacodynamics (PD) effect or through the Adsorption, Distribution, Metabolism, and Excretion (ADME) process, triggered when a bio-macromolecule interacts with a therapeutic drug. Therefore, the drug discovery process is important because 75% of diseases known to human kind are not all cured by therapeutics currently available in the market. This is attributed to the lack of knowledge of the function of targets and their therapeutic use in order to design therapeutics that would trigger their pharmacological responses. Accordingly, the focus of this work is to develop cost saving strategies for medicinal chemists involved with drug discovery projects. Therefore, studying the synergy between in silico and in vitro approaches maybe useful in the discovery of novel therapeutic compounds and their biological activities. In this work, in silico methods such as structure-based and ligand-based approaches were used in the design of the pharmacophore model, database screening and flexible docking methods. Specifically, this work is presented by the following case studies: The first involved molecular docking studies to predict the binding modes of catechin enantiomer to human serum albumin (HSA) interaction; the second involved the use of docking methods to predict the binding affinities and enantioselectivity of the interaction of warfarin enantiomers to HSA. the third case study involved a combined computational strategy in order to generate information on a diverse set of steroidal and non-steroidal CYP17A1 inhibitors obtained from literature with known experimental IC50 values. Finally, the fourth case study involved the prediction of the site of metabolisms (SOMs) of probe substrates to Cytochrome P450 metabolic enzymes CYP 3A4, 2D6, and 2C9 making use of P450 module from Schrödinger suite for ADME/Tox prediction. The results of case study I were promising as they were able to provide clues to the factors that drive the synergy between experimental kinetic parameters and computational thermodynamics parameters to explain the interaction between drug enantiomers and thetarget protein. These parameters were correlated/converted and used to estimate the pseudo enantioselectivity of catechin enantiomer to HSA. This approach of combining docking methodology with docking post-processing methods such as MM-GBSA proved to be vital in estimating the correct pseudo binding affinities of a protein-ligand complexes. The enantioselectivity for enantiomers of catechin to HSA were 1,60 and 1,25 for site I and site II respectively. The results of case study II validates and verifies the preparation of ligands and accounting for tautomers at physiological pH, as well as conformational changes prior to and during docking with a flexible protein. The log KS = 5.43 and log KR = 5.34 for warfarin enantiomer-HSA interaction and the enantioselectivity (ES = KS/KR) of 1.23 were close to the experimental results and hence referred to as experimental-like affinity constants which validated and verified their applicability to predict protein-ligand binding affinities. In case study III, a 3D-QSAR pharmacophore model was developed by using 98 known CYP17A1 inhibitors from the literature with known experimental IC50 values. The starting compounds were diverse which included steroidal and non-steroidal inhibitors. The resulting pharmacophore models were trained with 69 molecules and 19 test set ligands. The best pharmacophore models were selected based on the regression coefficient for a best fit model with R2 (ranging from 0.85-0.99) & Q2 (ranging from 0.80-0.99) for both the training and test sets respectively, using Partial Least Squares (PLS) regression. On the other hand, the best pharmacophore model selected was further used for a database screening of novel inhibitors and the prediction of their CYP17A1 inhibition. The hits obtained from the database searches were further subjected to a virtual screening workflow docked to CYP17A1 enzyme in order to predict the binding mode and their binding affinities. The resulting poses from the virtual screening workflow were subjected to Induced Fit Docking workflow to account for protein flexibility during docking. The resulting docking poses were examined and ranked ordered according to the docking scores (a measure of affinity). Finally, the resulting hits designed from an updated model from case study III were further synthesized in an external organic chemistry laboratory and the synthetic protocols as well as spectroscopic data for structure elucidation forms part of the provisional patent specification. A provisional patent specification has been filed (RSA Pat. Appln. 2015/ 07849). The case studies performed in this thesis have enabled the discovery of non-steroidal CYP17A1 inhibitors. / D

A ciclofosfamida (CPA) é um agente alquilante da classe das oxazafosforinas amplamente usada no tratamento de múltiplas formas de câncer e de doenças autoimunes em adultos e crianças. A CPA está disponível na clínica como racemato, no entanto, dados pré-clínicos demonstraram diferenças na eficácia e toxicidade dos seus enantiômeros, sendo o enantiômero (S)-(-)-CPA o de maior índice terapêutico. O presente estudo investigou a enantiosseletividade e a influência do CYP2B6, CYP2C9, CYP2C19 e CYP3A na disposição cinética da ciclofosfamida (CPA) em pacientes portadoras de câncer de mama. Foram incluídas na investigação 15 pacientes previamente submetidas ao procedimento de retirada do tumor e tratadas com CPA racêmica (900-1000 mg) e epirrubicina. A atividade in vivo do CYP3A foi avaliada empregando o midazolam como fármaco marcador. As amostras seriadas de sangue foram coletadas até 24 horas após a administração do primeiro ciclo da CPA. Os enantiômeros da CPA foram extraídos do plasma, usando mistura de acetato de etila:clorofórmio (75:25, v/v) e separados na coluna Chiralcel® OD-R com fase móvel constituída por acetonitrila:água (25:75, v/v), contendo 0,2% de ácido fórmico. Os enantiômeros da CPA foram analisados por LC-MS-MS, sendo que os íons protonados e seus respectivos íons-produtos foram monitorados nas transições 261>141 para a CPA e 189>104 para o padrão interno (antipirina). A recuperação foi maior que 95% para ambos os enantiômeros da CPA e o limite de quantificação foi de 2,5 ng/mL de plasma para cada enantiômero. Os coeficientes de variação e os erros relativos obtidos na avaliação da precisão e exatidão intra e inter-ensaios foram menores que 10%. Os parâmetros farmacocinéticos foram calculados empregando o programa WinNonlin e utilizando modelo monocompartimental e cinética de primeira ordem. Os parâmetros farmacocinéticos com razões enantioméricas diferentes da unidade foram avaliados com base no teste de Wilcoxon (P0,05). A disposição cinética da CPA é enantiosseletiva em pacientes com câncer de mama, com acúmulo plasmático do enantiômero (S)-(-)-CPA (AUC 195,00 vs 174,80 g.h/mL) em função do clearance preferencial do enantiômero (R)- (+)-CPA (5,13 vs 5,99 L/h). Os clearances de ambos os enantiômeros da ciclofosfamida não diferem em função dos genótipos CYP2B6, CYP2C9 e CYP2C19 e da atividade in vivo do CYP3A avaliada pelo clearance do midazolam. / Cyclophosphamide (CPA) is an alkylating oxazaphosphorine agent widely used in the treatment of multiple forms of cancer and autoimmunes disesases in adults and children. CPA is used as a racemic mixture, although preclinical data have demonstrated differences in the efficacy and toxicity of its enantiomers, with the (S)-(- )-CPA exhibiting a higher therapeutic index. The present study investigated the enantioselectivity and influence of CYP2B6, CYP2C9, CYP2C19 and CYP3A on the kinetic disposition of cyclophosphamide (CPA) in patients with breast cancer. Fifteen patients previously submitted to removal of the tumor and treated with racemic CPA (900-1000 mg) and epirubicin were included in the study. The in vivo activity of CYP3A was evaluated using midazolam as a marker drug. Serial blood samples were collected up to 24 h after administration of the first cycle of CPA. The CPA enantiomers were extracted from plasma using a mixture of ethyl acetate:chloroform (75:25, v/v) and separated on a Chiralcel® OD-R column, with the mobile phase consisting of acetonitrile:water (25:75, v/v) and 0.2% formic acid. The CPA enantiomers were analyzed by LC-MS-MS, and the protonated ions and their respective ion products were monitored at transitions of 261>141 for CPA and of 189>104 for the internal standard (antipyrine). Recovery was higher than 95% for both CPA enantiomers and the quantification limit was 2.5 ng/mL plasma for each enantiomer. The coefficients of variation and relative errors obtained for the evaluation of the intra- and interassay precision and accuracy were less than 10%. The pharmacokinetic parameters were calculated with the WinNonlin program using a monocompartmental model and first-order kinetics. The pharmacokinetic parameters presenting enantiomer ratios different from one were evaluated using the Wilcoxon test (P0.05). The kinetic disposition of CPA was enantioselective in patients with breast cancer, with plasma accumulation of the (S)-(-)-CPA enantiomer (AUC 195.00 vs 174.80 g.h/mL) due to the preferential clearance of the (R)-(+)-CPA enantiomer (5.13 vs 5.99 L/h). Clearances of both CPA enantiomers did not differ between the CYP2B6, CYP2C9 and CYP2C19 genotypes or as a function of in vivo activity of CYP3A evaluated by the midazolam clearance.

A diferença na atividade terapêutica, farmacocinética e / ou farmacodinâmica entre os enantiômeros de fármacos quirais impulsionou a necessidade de estudar e desenvolver métodos para determinação exata e precisa da pureza enantiomérica dos produtos farmacêuticos. Inicialmente, os enantiômeros foram separados em escala analítica. As condições analíticas foram adaptadas para a escala semi-preparativa para a obtenção enantiômeros puros. Os enantiômeros do bisoprolol foram separados através de Cromatografia Líquida de Alta Eficiência. Foi adotado o sistema direto de separação, fase normal, utilizando coluna Chiralcel OD (250 x 4,6 mm id). A fase móvel foi composta por hexano: etanol: dietilamina (80:20:0.2, v / v / v), vazão de 1mL/min e detecção em UV a 273 nm. A separação dos enantiômeros (R)-bisoprolol e (S)-bisoprolol foi obtida com sucesso em escala analítica e semi-preparativa. Considerando as características de uma separação quiral, podemos concluir que os resultados são eficazes, por ser uma separação rápida e seletiva. / The difference in therapeutic activity, pharmacokinetics, and / or pharmacodynamics between enantiomers of chiral drugs has raised the need to study and develop methods for accurate and precise determination of enantiomeric purity of pharmaceutical products. Initially, the enantiomers were separation in analytical scale. The analytical conditions were scaled up to semi-preparative level to obtain pure enantiomers. The enantiomers of bisoprolol were separated with high-performance liquid chromatography. Direct separation system was adopted in normal phase mode using Chiralcel OD column (250 x 4.6 mm id). The mobile phase was composed of hexane:ethanol:diethylamine (80:20:0.2, v/v/v), flow rate of 1mL/min and UV detection was made at 273 nm. The separation of enantiomers, (R)-bisoprolol and (S)-bisoprolol was successfully obtained in analytical and semi-preparative scale. Considering the characteristics of a chiral separation, we can conclude that the results are effective, because it is a fast and selective separation.

A fluoxetina, um fármaco quiral disponível para uso clínico, como uma mistura racêmica de (S)-(+)-fluoxetina e (R)-(-)-fluoxetina, é a droga mais utilizada no tratamento de estados depressivos durante a gravidez. N-desmetilação de fluoxetina por CYP2D6, CYP2C9 e CYP3A4 produz o seu metabólito ativo, norfluoxetina com os enantiômeros (S)-(+)-e (R)-(-)- norfluoxetina. Os objetivos deste estudo foram avaliar a farmacocinética, distribuição transplacentária e metabolismo da fluoxetina e norfluoxetina, em gestantes saudáveis. Foram avaliadas nove gestantes sem comorbidades. Todas receberam dose única de 20 mg de fluoxetina via oral em duas ocasiões distintas, sendo a primeira com 32 semanas e a segunda no dia do parto. Após a administração do fármaco, foram coletadas amostras seriadas de sangue materno para avaliação da concentração dos enantiômeros da fluoxetina, nos tempos de zero a 672 horas. No dia do parto, após receber a medicação, foram coletadas amostras sanguíneas materna no momento do nascimento, de sangue de vasos umbilicais, espaço interviloso, líquido amniótico para avaliação da transferência placentária. Vinte e quatro horas após o parto, foi coletada uma amostra de 3 mL de leite materno para avaliação de excreção. A análise dos enantiômeros da fluoxetina e norfluoxetina em plasma humano foi realizada por cromatografia líquida de alta eficiência (LC-MS/MS). O método de análise foi desenvolvido e validado de acordo com a RDC 27, ANVISA. As medianas dos parâmetros farmacocinéticos dos enantiômeros (S)-(+)- e (R)-(-)- da fluoxetina foram, respectivamente: Cmax 6,05 vs 5,94 ng/mL, t1/2 ? 1,94 vs 2,33 h, AUC0-? 97,81 vs 209,20 ng.h/mL, Cl/f 1,45 vs 0,66 L/h/kg, Vd/f 19,00 vs 23,25 L/kg. E dos parâmetros farmacocinéticos dos (S)-(+)- e (R)-(-)-norfluoxetina foram, respectivamente: Cmax 6,29 vs 3,29 ng/mL, t1/2 ? 83,48 vs 95,15 h, AUC0-? 942,70 vs 498,6 ng.h/mL. O método para análise dos enantiômeros da fluoxetina e norfluoxetina mostraram limites compatíveis com a aplicação de um estudo clínico envolvendo a administração de uma dose única. Foi observada enantiosseletividade em alguns parâmetros na farmacocinética e transferência placentária da fluoxetina e norfluoxetina em gestantes. / Fluoxetine, a chiral drug available for clinical use as a racemic mixture of (S)-(+)-fluoxetine and (R)-(-)-fluoxetine, is the most widely used drug in the treatment of depressive states during pregnancy. N-demethylation of fluoxetine by CYP2D6, CYP2C9 and CYP3A4 produce its active metabolite norfluoxetine as the enantiomers S-(+) and (R)-(-)-norfluoxetine. The objectives of this study were to evaluate the pharmacokinetics, transplacental distribution and metabolism of fluoxetine and norfluoxetine in healthy pregnant women. A total of nine pregnant women without comorbidities received a single oral dose of 20 mg fluoxetine on two separate occasions, the first in the 32 gestation weeks and the second at the day of delivery. After drug administration during the first sequential samples of maternal blood were collected at time zero until 672 hours. On the day of delivery, after receiving the medication maternal blood sample was collected at birth, umbilical blood vessels, intervillous space, and amniotic fluid sample for evaluation of placental drug transfer. Twenty-four hours after delivery was collected a sample of 3 ml of breast milk for analysis of excretion by this way. The analysis of the enantiomers of fluoxetine and norfluoxetine in human plasma was performed by high-performance liquid chromatography (LC-MS/MS) .The analytical method was developed and validated in accordance with the RDC 27, ANVISA. Median pharmacokinetic parameters of (S)-(+)- and (R)-(-)-fluoxetine enantiomers were: Cmax 6.05 vs 5.94 ng/mL, t1/2 ? 1.94 vs 2.33 h, AUC 0-? 97.81 vs 209.20 ng.hr/mL, Cl/f 1.45 vs 0.66 L/h/kg, Vd/f 19.00 vs 23.25 L/kg. The values of (S)-(+)- and (R)-(-)-norfluoxetine enantiomers were: Cmax 6.29 vs 3.29 ng/mL, t1/2 ? 83.48 vs 95.15 h, AUC 0-? 942.70 vs 498.6 ng.h/mL. Confidence method for sequence analysis of the enantiomers of fluoxetine and its active metabolites showed limits compatible with the application of a clinical study involving the administration of a single dose of pregnant women. Enantioselectivity was observed in some parameters of pharmacokinetics and placental fluoxetine and norfluoxetine transfer in healthy pregnant women.

A diferença na atividade terapêutica, farmacocinética e / ou farmacodinâmica entre os enantiômeros de fármacos quirais impulsionou a necessidade de estudar e desenvolver métodos para determinação exata e precisa da pureza enantiomérica dos produtos farmacêuticos. Inicialmente, os enantiômeros foram separados em escala analítica. As condições analíticas foram adaptadas para a escala semi-preparativa para a obtenção enantiômeros puros. Os enantiômeros do bisoprolol foram separados através de Cromatografia Líquida de Alta Eficiência. Foi adotado o sistema direto de separação, fase normal, utilizando coluna Chiralcel OD (250 x 4,6 mm id). A fase móvel foi composta por hexano: etanol: dietilamina (80:20:0.2, v / v / v), vazão de 1mL/min e detecção em UV a 273 nm. A separação dos enantiômeros (R)-bisoprolol e (S)-bisoprolol foi obtida com sucesso em escala analítica e semi-preparativa. Considerando as características de uma separação quiral, podemos concluir que os resultados são eficazes, por ser uma separação rápida e seletiva. / The difference in therapeutic activity, pharmacokinetics, and / or pharmacodynamics between enantiomers of chiral drugs has raised the need to study and develop methods for accurate and precise determination of enantiomeric purity of pharmaceutical products. Initially, the enantiomers were separation in analytical scale. The analytical conditions were scaled up to semi-preparative level to obtain pure enantiomers. The enantiomers of bisoprolol were separated with high-performance liquid chromatography. Direct separation system was adopted in normal phase mode using Chiralcel OD column (250 x 4.6 mm id). The mobile phase was composed of hexane:ethanol:diethylamine (80:20:0.2, v/v/v), flow rate of 1mL/min and UV detection was made at 273 nm. The separation of enantiomers, (R)-bisoprolol and (S)-bisoprolol was successfully obtained in analytical and semi-preparative scale. Considering the characteristics of a chiral separation, we can conclude that the results are effective, because it is a fast and selective separation.