Purpose:Omeprazole is a proton pump inhibitor (PPI) used in the treatment of gastrointestinal conditions, such as gastrointestinal esophageal reflux disease (GERD). Omeprazole is often prepared as an oral suspension to accommodate certain patients. Historically, oral suspensions of omeprazole were prepared using pharmaceutical compounding with sodium bicarbonate, but a kit for preparation of omeprazole oral suspension is available, FIRST® - Omeprazole. The purpose of this project is to compare the stability of the active pharmaceutical ingredient (API), omeprazole, in the FIRST® kit product to a traditionally compounded omeprazole suspension, when stored in refrigerated unit-dosed syringes. Methods: Five 100-mL batches of compounded omeprazole oral suspension (2 mg/mL) and five 300-mL kits of FIRST® - Omeprazole were prepared by a licensed pharmacist, and aliquoted into 5-mL doses in clear luer-lock plastic oral syringes, and stored at refrigerated temperature (2-8oC). Omeprazole concentration was assessed in each batch/kit on the day of preparation. Triplicate syringes from each batch/kit (n = 15 per test group per day) were removed after 7 days, 14 days, 21 days, and 30 days of refrigerated storage. Samples were diluted to assay concentration (1 mg/mL) in ion-free water and filtered using a 0.22-micron microcentrifuge filter tube. Samples were analyzed for omeprazole recovery using a validated high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method. Recovery was quantitatively assessed by comparing sample peak area to a freshly prepared calibration curve (1 – 0.125 mg/mL) using United States Pharmacopoeia (USP) reference standard on each day of sampling. Refrigerator temperatures were recorded daily using a digital thermometer. Results:Stability was defined as recovery of 90 - 110% of initial concentration of API. For the FIRST® - Omeprazole samples, the chemical potency remained within this window for the entire study period of 30 days. The compounded omeprazole suspension demonstrated a less than 90% average recovery at the day 21 sample. Furthermore, a statistically significant difference in the initial concentration was detected on the day of compounding (p = 0.0244), with the compounded omeprazole starting at 1.89 ± 0.10 mg/mL and the FIRST® - Omeprazole at 1.98 ± 0.04 mg/mL. After 30 days, the compounded omeprazole suspension had an 89.13% average API recovery (standard deviation; ± 5.17%) and the FIRST® - Omeprazole 97.20% API recovery (± 3.59%). Conclusion:Both traditionally compounded omeprazole suspension (2mg/mL) and FIRST® - Omeprazole suspension (2mg/mL) may be stored in clear luer-lock oral syringes under refrigeration for 14 days, and retain potency between 90 to 110% based on initial concentration. Furthermore, the FIRST® - Omeprazole suspension can be stored for the duration of the product’s beyond-use date of 30 days and retain potency between 90 to 110% of initial concentration or label claim. Finally, the data suggest that API concentration in FIRST® - Omeprazole suspension is more consistent from batch to batch than traditionally compounded omeprazole suspension.

No description available.

Este trabalho teve por finalidade o desenvolvimento e validação de métodos para análise estereosseletiva de alguns fármacos e metabólitos, bem como a aplicação desses métodos na avaliação do potencial de fungos, principalmente endofíticos, em processos de biotransformação. Os seguintes fármacos foram selecionados para esse estudo: fluoxetina, propranolol, omeprazol, oxibutinina e ibuprofeno. Para determinação simultânea dos enantiômeros da fluoxetina (FLX) e norfluoxetina (NFLX) em meios de cultura de fungos endofíticos, empregou-se a cromatografia líquida de alta eficiência com detecção por absorção no ultravioleta, em um sistema com duas colunas em série, sendo uma de fase reversa (C18) e outra com fase estacionária quiral (Chirobiotic® V). A fase móvel foi composta por etanol: tampão acetato de amônio 15 mmol L-1, pH 5,90: acetonitrila (77,5: 17,5: 5, v/v/v) e a detecção foi realizada em 227 nm. A extração líquido-líquido foi empregada na preparação das amostras. As curvas analíticas foram lineares no intervalo de concentração de 12,5 a 3750 ng mL-1 (r 0,996) para todos os enantiômeros analisados. Os coeficientes de variação e erros relativos obtidos nos estudos de precisão e exatidão foram inferiores a 10%. Nas condições empregadas, os cinco fungos endofíticos estudados não foram capazes de promover a biotransformação da FLX (reação de demetilação). A eletroforese capilar foi empregada para análise enantiosseletiva do propranolol (PROP) e 4-hidroxipropranolol (4-OHPROP). A melhor condição de resolução dos enantiômeros foi encontrada com a aplicação de um planejamento experimental de Box-Behnken: solução de eletrólitos composta por tampão trietilamina / ácido fosfórico (TEA/H3PO4), 25 mmol L-1, pH 9,00, carboximetil--ciclodextrina 4% (m/v) como seletor quiral e análise realizada na voltagem de 17 kV. O método de extração líquido-líquido também foi empregado para preparação das amostras. As curvas analíticas foram lineares no intervalo de concentração de 0,25 a 10,0 g mL-1 para 4-OHPROP e de 0,10 a 10,0 g mL-1 para PROP, apresentando coeficientes de correlação (r) 0,995 para todos os enantiômeros analisados. Os coeficientes de variação e erros relativos obtidos nos estudos de precisão e exatidão foram inferiores a 15%. Os cinco fungos endofíticos em estudo se mostraram eficientes na biotransformação estereosseletiva do PROP, com maior formação do metabólito (-)-(S)-4-OHPROP. O fungo Glomerella cingulata (VA1), em especial, apresentou uma concentração de 1,745 g mL-1 do enantiômero (-)-(S)-4-OHPROP depois de 72 horas de incubação, ao passo que a formação do enantiômero (+)-(R)-4-OHPROP não foi observada. A utilização deste fungo em escalas ampliadas pode ser uma fonte promissora de obtenção do metabólito 4-OHPROP na forma enantiomericamente pura. A determinação simultânea de omeprazol (OMZ), 5-hidroxiomeprazol (5-HOMZ) e omeprazol sulfona (OMZ SUL) em meio de cultura Czapek Dox modificado ii tamponado foi realizada empregando um método rápido de análise por cromatografia líquida de ultra eficiência com detector por arranjo de diodos (UPLC / DAD), usando coluna monolítica de fase reversa e eluição por gradiente. OMZ, 5-HOMZ e OMZ SUL foram extraídos das amostras utilizando uma mistura de acetato de etila: t-butil metil éter (9: 1, v/v). A separação foi obtida empregando uma coluna RP 18 Chromolith Fast Gradient endcapped e fase móvel constituída por 0,15% (v/v) de ácido trifluoroacético (TFA) em água (solvente A) e 0,15% (v/v) de TFA em acetonitrila (solvente B). Os tempos de retenção foram de 0,70 min para 5-HOMZ, 0,74 min para OMZ, 0,77 min para OMZ SUL e 0,91 min para o padrão interno (bupropiona, BUP). O método foi linear no intervalo de 0,2 a 10,0 g mL-1 (r 0,995) para todos os analitos. O processo de biotransformação foi realizado durante apenas 24 horas de incubação, por causa de problemas de estabilidade do OMZ. Por esse mesmo motivo, a biotransformação estereosseletiva não foi avaliada. Apenas três fungos apresentaram formação do metabólito 5-HOMZ, e dentre estes, apenas o fungo Botritis cinerea (BC) produziu esse metabólito em concentração superior ao limite de quantificação do método. A formação do metabólito OMZ SUL foi observada para todos os fungos, exceto para Glomerella cingulata (VA1) e Guignardia mangiferae (VA15). Esses fungos podem ser úteis para a obtenção dos metabólitos do OMZ, mas estudos detalhados do comportamento do fármaco nas condições de cultivo são necessários, uma vez que este substrato pode sofrer degradação em meio ácido e na presença de luz. A análise simultânea dos enantiômeros da oxibutinina (OXY) e da N-desetiloxibutinina (DEOB) em meio de cultura Czapek foi obtida empregando a cromatografia líquida de alta eficiência com detector UV (HPLC/UV). Os analitos foram separados usando coluna quiral Chiralpak AD e fase móvel constituída por hexano: isopropanol: etanol: dietilamina (94: 4: 2: 0,05, v/v/v/v) e detectados em 210 nm. Um estudo piloto de biotransformação empregando os mesmos fungos e as condições de biotransformação utilizadas para os demais fármacos mostrou que não houve a formação do metabólito de interesse. Além disso, não houve uma diminuição significativa da concentração de OXY durante o período de incubação, o que poderia ser um indicativo da formação de outros metabólitos não monitorados nas condições de análise. Como a reação de desetilação da OXY para formar a DEOB não foi observada nos experimentos, não foi necessário realizar a validação do método analítico. A separação simultânea do ibuprofeno (IBP), dos enantiômeros do 2-hidroxi-ibuprofeno (2-OH-IBP) e dos estereoisômeros do carboxi-ibuprofeno (COOH-IBP) foi realizada empregando-se uma coluna Chiralpak AS-H e fase móvel constituída por hexano: isopropanol: TFA (95: 5: 0,1, v/v/v). O solvente extrator usado na extração líquido-líquido foi uma mistura de hexano: acetato de etila (1: 1, v/v). A detecção foi feita por espectrometria de massas (MS/MS), com a fonte de ionização por eletronebulização operada no modo positivo (ESI+). O método foi linear nos intervalos de 0,1 a 20,0 g mL-1 para IBP, de 0,05 a 7,5 g mL-1 para o cada enantiômero do 2-OH-IBP e de 0,025 a 5,0 g mL-1 para cada estereoisômero do COOH-IBP. Os demais parâmetros de validação obtidos para o método apresentaram-se dentro dos limites recomendados pela literatura. Os sete fungos endofíticos estudados se mostraram eficientes na biotransformação do IBP em seu principal metabólito 2-OH-IBP, mas apenas os fungos Nigrospora sphaerica (SS67) e Chaetomium globosum (VR10) iii biotransformaram o IBP de forma enantiosseletiva mais acentuada, observando-se maior formação do metabólito ativo (+)-(S)-2-OH-IBP. A não estereosseletividade observada para os demais fungos pode ser indício de uma possível conversão quiral do fármaco, similar a que ocorre em humanos. A formação dos estereoisômeros do COOH-IBP não foi observada, provavelmente, porque sua rota de formação envolve uma seqüência de reações. Os resultados apresentados nesse trabalho mostram que fungos, particularmente os endofíticos, podem ser uma fonte promissora para obtenção de metabólitos de fármacos, inclusive de forma enantiomericamente pura. / This work aimed the development and validation of suitable methods for the stereoselective analysis of some drugs and metabolites, as well as, the application of these methods to assess the potential of fungi, mainly the endophytic ones, in biotransformation processes. The following drugs were selected for this study: fluoxetine, propranolol, omeprazole, oxybutynin and ibuprofen. The simultaneous determination of fluoxetine (FLX) and norfluoxetine (NFLX) enantiomers in culture media of endophytic fungi was carried out by high-performance liquid chromatography with UV-detection, in a system of two columns coupled in series, in which one of them was a reversed phase (C18) column and the another one was a chiral stationary phase column (Chirobiotic ® V). The mobile phase consisted of ethanol: ammonium acetate buffer, 15 mol L-1, pH 5.90: acetonitrile (77.5: 17.5: 5, v/v/v) and the detection was performed at 227 nm. Liquid-liquid extraction was employed for sample preparation. The analytical curves were linear over the concentration range of 12.5 to 3750 ng mL-1 (r 0.996) for all enantiomers evaluated. The coefficients of variation and relative errors obtained in the evaluation of method precision and accuracy were lower than 10%. In the studied conditions, the five endophytic fungi used were not able to perform the biotransformation of FLX (demethylation reaction). Capillary electrophoresis was employed for the enantioselective analysis of propranolol (PROP) and 4-hydroxypropranolol (4-OHPROP). The best condition for enantiomer resolution was obtained by applying an experimental design of Box-Behnken: electrolyte solution composed of triethylamine / phosphoric acid (TEA/H3PO4) buffer, 25 mmol L-1, pH 9.00, with 4% (w/v) carboxymethyl--cyclodextrin as the chiral selector and analysis performed at 17 kV. Liquid-liquid extraction was also used for sample preparation. The analytical curves were linear over the concentration range of 0.25 to 10.0 g mL-1 for 4-OHPROP and 0.10 to 10.0 g mL-1 for PROP, presenting correlation coefficients (r) 0.995 for all enantiomers evaluated. The coefficients of variation and relative errors obtained in the evaluation of precision and accuracy were lower than 15%. All the five endophytic fungi (Phomopsis sp. (TD2), Glomerella cingulata (VA1), Penicillium crustosum (VR4), Chaetomium globosum (VR10) and Aspergillus fumigatus (VR12)) showed effectiveness in the stereoselective biotransformation of PROP, with higher formation of (-)-(S)-4-OH-PROP. The fungus Glomerella cingulata (VA1), in particular, showed a concentration of 1.745 g mL-1 for the enantiomer (-)-(S)-4-OHPROP after 72 hours of incubation, whereas there was no formation of the enantiomer (+)-(R)-4-OHPROP. Therefore, the use of this fungus in large scale may be a promising source to obtain 4-OHPROP in the enantiomerically pure form. A fast analytical method based on ultra-performance liquid chromatography / diode array detector (UPLC/DAD) using a monolithic reversed phase column and gradient elution was developed for the simultaneous determination of omeprazole (OMZ), 5-hydroxyomeprazole (5-HOMZ) and omeprazole sulfone (OMZ SUL) in modified and buffered Czapek-Dox culture medium. OMZ, 5-HOMZ and OMZ SUL were extracted using a mixture of ethyl acetate: methyl t-butyl ether (9: 1, v/v). The separation was achieved using a Chromolith Fast Gradient RP 18 endcapped column with the mobile phase consisting of 0.15% (v/v) trifluoroacetic acid (TFA) in water (solvent A) and 0.15% (v/v) TFA in acetonitrile (solvent B). Retention times were 0.70 min for 5-HOMZ, 0.74 min for OMZ, 0.77 min for OMZ SUL and 0.91 min for internal standard (bupropion, BUP). The method was linear over the concentration range of 0.2 to 10.0 g mL-1 (r 0.995) for all analytes. The biotransformation process was carried out only within 24 hours of incubation, due to OMZ instability. For the same reason, the stereoselectivity in this process was not evaluated. The formation of the metabolite 5-HOMZ was observed only for three fungi, and among them, only the fungus Botrytis cinerea (BC) produced this metabolite in concentrations higher than the limit of quantification. The formation of OMZ SUL was observed for all fungi, except for Guignardia mangiferae (VA1) and Glomerella cingulata (VA15). The fungi evaluated in this study can be useful to obtain the metabolites of OMZ, but detailed study of the drug stability in culture conditions is required, since this substrate can undergo degradation in acidic conditions and in the presence of light. The simultaneous analysis of oxybutinin (OXY) and N-desethyloxybutinin (DEOB) enantiomers in Czapek culture medium was carried out by liquid chromatography with UV detection (HPLC/UV). The analytes were separated using a Chiralpak AD column employing as mobile phase hexane: isopropanol: ethanol: diethylamine (94: 4: 2: 0.05, v/v/v/v) and detection at 210 nm. A pilot study of biotransformation using the same fungi and conditions employed for the biotransformation of the other drugs showed that the metabolite of interest was not formed. Moreover, the decrease in the concentration of OXY, which could be indicative of the formation of other metabolites not monitored under the conditions of analysis, was not observed. Since the reaction of OXY desethylation to form DEOB was not observed in the experiments, the validation of the analytical method was not required. The method for the simultaneous analysis of ibuprofen (IBP), 2-hydroxyibuprofen (2-OH-IBP) enantiomers and carboxyibuprofen (IBP-COOH) stereoisomers was developed using a Chiralpak AS-H column and a mobile phase consisting of hexane: isopropanol: TFA (95: 5: 0.1, v/v/v). A mixture of hexane: ethyl acetate (1: 1, v/v) was used as solvent extractor for sample preparation. The detection was performed by tanden mass spectrometry (MS/MS) with the electrospray interface operated in the positive mode (ESI+). The method was linear over the concentration range of 0.1 to 20.0 g mL-1 for IBP, 0.05 to 7.5 g mL-1 for each 2-OH-IBP enantiomer and 0.025 to 5.0 g mL-1 for each COOH-IBP stereoisomer. The other validation parameters studied were within the limits established in the literature. The seven studied endophytic fungi showed to be efficient in the biotransformation of IBP to its main metabolite 2-OH-IBP, however, only the fungi Nigrospora sphaerica (SS67) and Chaetomium globosum (VR10) biotransformed IBP enantioselectively, with greater formation of the active metabolite (+)-(S)-2-OH-IBP. The lack of stereoselectivity observed for the other fungi could be caused by a possible chiral inversion process occurring for IBP, in a similar way that happens in humans. The formation of COOH-IBP stereoisomers was not observed probably because the route of formation of this metabolite requires a sequence of reactions. The results presented here show that fungi, particularly the endophytic ones, may be a promising source to obtain the metabolites of drugs, including in their enantiomerically pure form.

INTRODUÇÃO: Os Inibidores de Bombas de Prótons (IBP´s) são comumente prescritos a pacientes em uso de dupla antiagregação plaquetária (DAP) com ácido acetilsalicílico (AAS) e clopidogrel. Entretanto, esta classe de medicamentos, especialmente o omeprazol, tem sido associada à redução da potência antiplaquetária do clopidogrel, levando em muitos casos ao uso de ranitidina como alternativa. MÉTODOS: Foram analisados pacientes com doença arterial coronária (DAC) estável em uso de AAS 100 mg uma vez ao dia. A agregabilidade plaquetária foi medida no momento basal e após uma semana de terapia com clopidogrel na dose de 75 mg uma vez ao dia. Após essa fase inicial, os participantes foram randomizados de modo duplo-cego e duplo-mascarado para omeprazol 20 mg duas vezes dia ou ranitidina 150 mg duas vezes ao dia, sendo os testes de agregação plaquetária novamente repetidos após uma semana. A agregabilidade foi avaliada com a utilização dos seguintes métodos: VerifyNow P2Y12® (Accumetrics - San Diego, CA, EUA, meta principal do estudo), utilizando-se Unidades de Reatividade ao P2Y12 (\"P2Y12 Reactivity Units\" - PRU) e Inibição Percentual da Agregabilidade (IPA) na descrição da agregabilidade; agregometria de sangue total (AST) por bioimpedância utilizando os reagentes ADP e colágeno, sendo a agregabilidade medida em Ohms; \"Platelet Function Analyser\" 100® (Siemens Healthcare Diagnostics®, Newark, Delaware, EUA) utilizando o cartucho de colágeno/ADP, com a agregabilidade avaliada pelo tempo de fechamento do orifício em segundos. Além disso, foi feita dosagem de tromboxano B2 (TXB2) sérico na última visita a fim de se avaliar o efeito do AAS. RESULTADOS: Oitenta e cinco pacientes foram incluídos na análise final, sendo 41 no grupo omeprazol e 44 no grupo ranitidina. Houve redução significativa da IPA após o acréscimo de omeprazol (de 26,3 ± 32,9% para 17,4 ± 33,1%; P = 0,025), enquanto o grupo ranitidina não demonstrou modificação significativa (de 32,6 ± 28,9% para 30,1 ± 31,3%; P = 0,310). Levando-se em conta o valor em PRU, houve um aumento numérico porém não significativo estatisticamente no grupo omeprazol (de 159,73 ± 83,06 para 173,54 ± 72,29; P = 0,116) enquanto no grupo ranitidina houve uma diferença muito pequena (de 153,61 ± 70,12 to 158,77 ± 76,37; P = 0,440). Em relação aos demais testes de agregabilidade e à dosagem de TXB2 sérico, não houve alterações significativas em qualquer um dos grupos. CONCLUSÃO: A ranitidina não influenciou o efeito antiplaquetário do clopidogrel, ao contrário do omeprazol, que reduziu a atividade antiplaquetária do medicamento. Esses achados podem ter um importante impacto na tomada de decisão quanto ao protetor gástrico a ser utilizado em pacientes submetidos a DAP com AAS e clopidogrel. / BACKGROUND: Proton-pump inhibitors (PPIs) are often prescribed to patients taking dual antiplatelet therapy (DAPT) with acetylsalicylic acid (ASA) and clopidogrel. However, this class of medication, especially omeprazole, has been associated with a reduction of clopidogrel efficacy, leading many to substitute omeprazole with ranitidine. METHODS: The present study analyzed patients with stable coronary artery disease (CAD) in use of ASA 100 mg daily. Platelet aggregability was measured at baseline and after one week of clopidogrel 75 mg daily. Then, the subjects were randomized, in a double-blinded, doubledummy fashion, to omeprazole 20 mg twice a day or ranitidine 150 mg twice a day. After one more week, aggregability tests were repeated. Platelet aggregability was evaluated by the following methods: VerifyNow P2Y12TM (Accumetrics - San Diego, California, USA, main endpoint of the study), with aggregability depicted as percent Inhibition of Platelet Aggregation (IPA) and as P2Y12 Reactivity Units (PRU); whole blood aggregometry by bioimpendance using ADP and collagen with aggregability measured in Ohms; and Platelet Function Analyser 100TM (Siemens Healthcare Diagnostics, Newark, Delaware, USA) using collagen/ADP cartridge with aggregability measured in time to closure in seconds. Besides that, serum thromboxane B2 dosage was done on the last visit to evaluate ASA effect. RESULTS: Eighty-five patients were included in final analysis (41 in the omeprazole group and 44 in the ranitidine group). IPA was significantly decreased after addition of omeprazole (from 26.3% ± 32.9 to 17.4% ± 33,1; P = 0.025), with no significant changes being observed in the ranitidine group (from 32.6% ± 28.9 to 30.1% ± 31.3; P = 0.310). When taking into account PRU values, there was a numerical, but statistically non-significant increase in the omeprazole group (from 159.73 ± 83.06 to 173.54 ± 72.29; P = 0.116), with a very slight difference in the ranitidine group (from 153.61 ± 70.12 to 158.77 ± 76.37; P = 0.44). There were no significant changes taking into account other aggregability tests and serum thromboxane B2 dosage. CONCLUSION: In patients with stable CAD, ranitidine did not influence clopidogrel antiplatelet activity, in contrast to omeprazole, which reduced antiplatelet drug effect. These findings may have a great impact in clinical decision making regarding gastrointestinal prophylaxis choice in patients taking DAPT with ASA and clopidogrel

INTRODUÇÃO: Os Inibidores de Bombas de Prótons (IBP´s) são comumente prescritos a pacientes em uso de dupla antiagregação plaquetária (DAP) com ácido acetilsalicílico (AAS) e clopidogrel. Entretanto, esta classe de medicamentos, especialmente o omeprazol, tem sido associada à redução da potência antiplaquetária do clopidogrel, levando em muitos casos ao uso de ranitidina como alternativa. MÉTODOS: Foram analisados pacientes com doença arterial coronária (DAC) estável em uso de AAS 100 mg uma vez ao dia. A agregabilidade plaquetária foi medida no momento basal e após uma semana de terapia com clopidogrel na dose de 75 mg uma vez ao dia. Após essa fase inicial, os participantes foram randomizados de modo duplo-cego e duplo-mascarado para omeprazol 20 mg duas vezes dia ou ranitidina 150 mg duas vezes ao dia, sendo os testes de agregação plaquetária novamente repetidos após uma semana. A agregabilidade foi avaliada com a utilização dos seguintes métodos: VerifyNow P2Y12® (Accumetrics - San Diego, CA, EUA, meta principal do estudo), utilizando-se Unidades de Reatividade ao P2Y12 (\"P2Y12 Reactivity Units\" - PRU) e Inibição Percentual da Agregabilidade (IPA) na descrição da agregabilidade; agregometria de sangue total (AST) por bioimpedância utilizando os reagentes ADP e colágeno, sendo a agregabilidade medida em Ohms; \"Platelet Function Analyser\" 100® (Siemens Healthcare Diagnostics®, Newark, Delaware, EUA) utilizando o cartucho de colágeno/ADP, com a agregabilidade avaliada pelo tempo de fechamento do orifício em segundos. Além disso, foi feita dosagem de tromboxano B2 (TXB2) sérico na última visita a fim de se avaliar o efeito do AAS. RESULTADOS: Oitenta e cinco pacientes foram incluídos na análise final, sendo 41 no grupo omeprazol e 44 no grupo ranitidina. Houve redução significativa da IPA após o acréscimo de omeprazol (de 26,3 ± 32,9% para 17,4 ± 33,1%; P = 0,025), enquanto o grupo ranitidina não demonstrou modificação significativa (de 32,6 ± 28,9% para 30,1 ± 31,3%; P = 0,310). Levando-se em conta o valor em PRU, houve um aumento numérico porém não significativo estatisticamente no grupo omeprazol (de 159,73 ± 83,06 para 173,54 ± 72,29; P = 0,116) enquanto no grupo ranitidina houve uma diferença muito pequena (de 153,61 ± 70,12 to 158,77 ± 76,37; P = 0,440). Em relação aos demais testes de agregabilidade e à dosagem de TXB2 sérico, não houve alterações significativas em qualquer um dos grupos. CONCLUSÃO: A ranitidina não influenciou o efeito antiplaquetário do clopidogrel, ao contrário do omeprazol, que reduziu a atividade antiplaquetária do medicamento. Esses achados podem ter um importante impacto na tomada de decisão quanto ao protetor gástrico a ser utilizado em pacientes submetidos a DAP com AAS e clopidogrel. / BACKGROUND: Proton-pump inhibitors (PPIs) are often prescribed to patients taking dual antiplatelet therapy (DAPT) with acetylsalicylic acid (ASA) and clopidogrel. However, this class of medication, especially omeprazole, has been associated with a reduction of clopidogrel efficacy, leading many to substitute omeprazole with ranitidine. METHODS: The present study analyzed patients with stable coronary artery disease (CAD) in use of ASA 100 mg daily. Platelet aggregability was measured at baseline and after one week of clopidogrel 75 mg daily. Then, the subjects were randomized, in a double-blinded, doubledummy fashion, to omeprazole 20 mg twice a day or ranitidine 150 mg twice a day. After one more week, aggregability tests were repeated. Platelet aggregability was evaluated by the following methods: VerifyNow P2Y12TM (Accumetrics - San Diego, California, USA, main endpoint of the study), with aggregability depicted as percent Inhibition of Platelet Aggregation (IPA) and as P2Y12 Reactivity Units (PRU); whole blood aggregometry by bioimpendance using ADP and collagen with aggregability measured in Ohms; and Platelet Function Analyser 100TM (Siemens Healthcare Diagnostics, Newark, Delaware, USA) using collagen/ADP cartridge with aggregability measured in time to closure in seconds. Besides that, serum thromboxane B2 dosage was done on the last visit to evaluate ASA effect. RESULTS: Eighty-five patients were included in final analysis (41 in the omeprazole group and 44 in the ranitidine group). IPA was significantly decreased after addition of omeprazole (from 26.3% ± 32.9 to 17.4% ± 33,1; P = 0.025), with no significant changes being observed in the ranitidine group (from 32.6% ± 28.9 to 30.1% ± 31.3; P = 0.310). When taking into account PRU values, there was a numerical, but statistically non-significant increase in the omeprazole group (from 159.73 ± 83.06 to 173.54 ± 72.29; P = 0.116), with a very slight difference in the ranitidine group (from 153.61 ± 70.12 to 158.77 ± 76.37; P = 0.44). There were no significant changes taking into account other aggregability tests and serum thromboxane B2 dosage. CONCLUSION: In patients with stable CAD, ranitidine did not influence clopidogrel antiplatelet activity, in contrast to omeprazole, which reduced antiplatelet drug effect. These findings may have a great impact in clinical decision making regarding gastrointestinal prophylaxis choice in patients taking DAPT with ASA and clopidogrel

OBJECTIVE The purpose of this study was to examine the stability of a generic lansoprazole product in a 3 mg/mL sodium bicarbonate suspension under room temperature and refrigerated conditions. METHODS Lansoprazole suspensions (3 mg/mL) were prepared in triplicate using an 8.4% sodium bicarbonate vehicle for each storage condition (room temperature and refrigerated). During 1 month, samples from each replicate were periodically removed and analyzed for lansoprazole concentration by liquid chromatography–tandem mass spectrometry (LC-MS/MS). Each sample was spiked with 10 mg/L omeprazole to serve as the internal standard. A positive electrospray LC-MS/MS method was validated over the calibration range of 5 to 25 mg/L using Food and Drug Administration Guidance. The identities of the analyte and internal standard in the samples were verified by monitoring the MS/MS transitions of m/z 370 to m/z 252 and m/z 346 to m/z 198 for lansoprazole and omeprazole, respectively. Additionally, the pH of the suspensions was monitored throughout the study. RESULTS The stability of lansoprazole in the oral sodium bicarbonate suspension under refrigeration is compromised prior to what has been previously reported in the literature. Samples kept at room temperature lost >10% of the lansoprazole after 48 hours compared with the refrigerated samples, which maintained integrity up to 7 days. No statistically significant difference was found between the pH of the room temperature and refrigerated suspension samples, indicating that this factor is not the cause for the differences in stability at these two conditions. CONCLUSIONS This study suggests that the extemporaneously compounded lansoprazole oral suspension prepared in 8.4% sodium bicarbonate should not be stored in plastic oral syringes longer than 48 hours at room temperature and no longer than 7 days when refrigerated. These data indicate an expiration time earlier than that previously reported for the refrigerated product (14 days).

Gastrointestinal symptoms have a prevalence of 20-40% in the general adult population in the Western world. These symptoms are generally considered to be poor predictors of organic findings [e.g. peptic ulcer disease (PUD) or malignancy]. Approximately 50% of patients seeking care for such symptoms have no organic explanation for these upon investigation. When other organic or other functional conditions are excluded [e.g. PUD, gastroesophageal reflux disease (GERD), irritable bowel syndrome (IBS)] the remaining patients are labelled as having functional dyspepsia (persistent or recurrent pain and/or discomfort centred in the upper abdomen). Management of functional dyspepsia remains a challenge, reflecting the heterogeneity of the patients and the uncertain role of drug treatment. Also, prognostic factors for treatment success are largely unknown. I have therefore performed a series of studies to shed light on these issues: The first study (Paper I) was performed in a randomly selected adult population (n=1,001) assessing upper and lower gastrointestinal symptoms at two occasions with 1 to 6 month intervals. The results show that gastrointestinal symptoms are common (57%) and fluctuate to some extent in the shorter term. Troublesome dyspeptic symptoms remain in two out of three individuals. This proportion was similar whether or not organic findings were present. In the second study (Paper II) 799 patients with dyspeptic symptoms were evaluated with regard to whether gastrointestinal symptoms, identified by self-administered questionnaires, correlate with endoscopic diagnoses and discriminate organic from non-organic (functional) dyspepsia. The impact of dyspeptic symptoms on health-related well-being was also evaluated. Approximately 50% of these dyspeptic patients were found to have functional dyspepsia at upper endoscopy. A difference was discovered in the symptom profile between patients with organic and functional dyspepsia. Predicting factors for functional dyspepsia were found. This study shows that use of self-administered symptom questionnaires may aid in clinical decision making for patient management, e.g. by reducing the number of endoscopies, although probabilities of risks for organic dyspepsia are difficult to transfer to management of the individual patient. The results also indicate that the health-related well-being in patients with functional and organic dyspepsia is impaired to the same extent, illustrating the need for effective treatment of patients with functional dyspepsia, a group not well served by currently available treatment modalities. The aim of the third study (Paper III) was to develop and evaluate a selfadministered questionnaire focusing on upper abdominal and reflux complaints to allow for identification of patients with heartburn and factors that might predict symptom relief with omeprazole both in GERD and functional dyspepsia patients. The diagnostic validity of the questionnaire was tested against endoscopy and 24-hour pH monitoring. The questionnaire had a sensitivity of 92%, but a low specificity of 19%. Symptom relief by omeprazole was best predicted by the presence of predominant heartburn described as ‘a burning feeling rising from the stomach or lower chest up towards the neck’ and ‘relief from antacids’. These results indicate that this questionnaire which used descriptive language, appeared to be useful in identifying heartburn and predicting responses to omeprazole in patients with upper gastrointestinal symptoms. The fourth study (Paper IV) was a pilot study investigating the symptom response to omeprazole 20 mg twice daily or placebo for a duration of 14 days in 197 patients with functional dyspepsia. We concluded that a subset of patients with functional dyspepsia, with or without heartburn, would respond to therapy with omeprazole. In the final study (Paper V) the aim was to identify prognostic factors for the treatment success to a 4-week course of omeprazole 10 or 20 mg once daily in 826 patients with functional dyspepsia. The most highly discriminating predictor of treatment success was the number of days without dyspeptic symptoms during the first week of treatment. Fewer days with symptoms during the first week indicated higher response rates at four weeks. In addition, positive predictors of treatment response to omeprazole were identified as age >40 years, bothersome heartburn, low scores of bloating and diarrhoea, history of symptoms for <3 months and low impairment of vitality at baseline. The results indicate that early response during the first week to treatment with a proton pump inhibitor seems to predict treatment success after four weeks in patients with functional dyspepsia. Conclusion: These studies have shown that a large proportion of adult individuals in society, both those who seek and those who do not seek medical care, suffer from symptoms located in the upper part of the abdomen regardless of whether an organic cause is present. A subset of patients without organic findings and other functional conditions, i.e. functional dyspepsia, respond to therapy with omeprazole irrespective of the presence or absence of heartburn . An excellent way to predict the response to a full course of omeprazole in functional dyspepsia is to assess the early response (first week) to treatment. These findings allow for better and faster targeting of acid inhibitory therapy in functional dyspepsia, which potentially can result in more effective clinical management of these patients and savings of health care resources.

Made available in DSpace on 2015-03-26T13:46:57Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1766831 bytes, checksum: 62438b176456ba87c3a689b13d0f0421 (MD5) Previous issue date: 2010-06-08 / The experiment took eight adult bitches, clinically healthy, mixed breed, weighing between 9 and 28 Kg. These animals formed two study groups at different times. At first the dogs comprised the control group and a moment later the same dogs formed the omeprazole group, with the aim of evaluating by endoscopy the period of healing of experimental gastric ulcer and effect of omeprazole in the treatment of this condition. The experiment was conducted at the Department of Veterinary, Federal University of Viçosa. The ulcerative gastropathy was induced by instilling 0.1 ml of sodium hydroxide at 40% through endoscopic visualization in the gastric mucosa in the pyloric antrum region. Dogs omeprazole group received 1 mg/kg of the drug orally for 24 in 24 hours during four weeks and the control group received placebo at the same moments. During the experiment, animals were assessed by daily physical examination, laboratory tests (CBC) before starting the experiment and at the end of the study, endoscopic examinations before the study began, and after induction of ulcerative gastropathy occur weekly until complete healing of lesions. The results showed that animals treated with omeprazole had better clinical and laboratory demonstrated endoscopic healing faster with a total recovery of the animals after 28 days, compared with 42 days required for full recovery of the control group. / Foram utilizadas 8 cadelas adultas, clinicamente sadias, sem raça definida, pesando entre 9 e 28 Kg. Estes animais formaram 2 grupos de estudo em momentos diferentes. No primeiro momento as cadelas compuseram grupo controle e num momento posterior as mesmas cadelas formaram o grupo omeprazol, com o objetivo de avaliar por endoscopia o período de cicatrização da mucosa gástrica ulcerada experimentalmente e o efeito do omeprazol no tratamento dessa condição. O experimento foi realizado no Departamento de Veterinária da Universidade Federal de Viçosa. A gastropatia ulcerativa foi induzida instilando-se 0,1 ml do hidróxido de sódio a 40% sob visualização endoscópica na mucosa gástrica em região de antro pilórico. Os cães do grupo omeprazol receberam 1 mg/kg do medicamento, via oral, de 24 em 24 horas, durante 4 semanas e os animais do grupo controle receberam placebo nos mesmos momentos. Durante o experimento, os animais foram avaliados por meio de exames clínicos diários; exames laboratoriais (hemograma) antes de se iniciar o experimento e ao término do estudo; exames endoscópicos antes do início do estudo, e após a indução da gastropatia ulcerativa semanalmente até ocorrer a completa cicatrização das lesões. Os resultados mostraram que os animais tratados com omeprazol tiveram melhor evolução clínica e laboratorial e demonstraram endoscopicamente uma cicatrização mais acelerada com total recuperação dos animais após 28 dias, em comparação aos 42 dias requeridos para total recuperação dos animais do grupo controle.

Made available in DSpace on 2015-03-26T13:46:58Z (GMT). No. of bitstreams: 1 texto completo.pdf: 310325 bytes, checksum: 8f99831e111c9711f091abefd7495890 (MD5) Previous issue date: 2011-03-11 / The antisecretory gastric acid drugs are widely used in veterinary medicine, however there are few studies on these drugs in dogs being that many of these data are taken from human medicine. Among these drugs, one of the most used is the omeprazole due to its bigger potency by blocking the hydrochloric acid production in the stomach. This study aimed to measure the gastric pH in healthy dogs after administration of two different doses of omeprazole at different times of evaluation. Six clinically healthy adult female dogs were selected weighing between 10 and 15 kg. All animals received a percutaneous gastrostomy tube (PEG) first placed with endoscopic assistance and the gastric content was collected for measurement of pH (pH meter), performed using a portable digital pH meter. Before omeprazole administration, the gastric pHs of all animals in the study were measured every two hours for seven days in order to elaborate a control pH curve. Thereupon this period, the dogs were submitted to daily administration of omeprazole orally at a dose of 1.5mg/kg SID for seven days and had their measurements taken every two hours during those days. Five days after the end of the last measurement, a new week experiment was also performed by changing the dosage of the omeprazole to 3.0mg/kg. The week control revealed that the measured pH values were variable throughout the day, although very acidic in most of the time. With the use of omeprazole at a dosage of 1,5mg/kg, gastric pH values showed lower acidity (average pH value = 3.260) compared to control weeks (average pH value = 2.487) and evidenced less variation during the day. At a dose of 3,0mg/kg the pH was even less acidic, presented more stable values than previous weeks, and got closer to the required standards of acid suppression for treatment of gastritis and gastroduodenal ulcers in humans. It follows that the omeprazole dosage of 3,0mg/kg was the most appropriate for achieving the desired acid suppression in the treatment of stomach diseases. / Fármacos antissecretores de ácido gástrico são comumente utilizados na medicina veterinária, entretanto existem poucos estudos com esses medicamentos em cães, sendo que muitos desses dados são obtidos da medicina humana. Dentre estes fármacos um dos mais utilizados é o omeprazol, devido sua maior potência na redução da produção de ácido clorídrico no estômago. O presente estudo teve por objetivo mensurar o pH gástrico de cães sadios após a administração de duas doses diferentes de omeprazol em tempos distintos de avaliação. Foram selecionados seis cães, adultos, fêmeas, com peso entre 10 e 15 Kg e clinicamente saudáveis. Todos os animais receberam uma sonda de gastrostomia percutâneo (PEG) colocado previamente com auxílio endoscópico e o conteúdo gástrico foi coletado para mensuração do pH (phmetria), realizada com o uso de um pHmetro portátil digital. Antes da administração do omeprazol, o pH gástrico de todos os animais envolvidos no estudo foi mensurado, a cada duas horas, durante sete dias, visando a confecção de uma curva controle de pH. Logo após esse período os cães foram submetidos a administração diária de omeprazol, por via oral, na dose de 1,5 mg/kg/SID, durante sete dias e tiveram suas mensurações realizadas a cada duas horas durante estes sete dias. Após cinco dias do término da última mensuração, uma nova semana experimental foi igualmente realizada alterandose a dosagem do omeprazol para 3,0 mg/Kg. Na semana controle observou-se que os valores mensurados de pH eram variáveis ao longo do dia, entretanto se mostraram muito ácidos na maior parte do tempo. Com o uso do omeprazol na dosagem de 1,5mg/kg os valores do pH gástrico apresentaram menor acidez (valor médio de pH=3,260) em relação a semana controle (valor médio de pH=2,487) e menos variações durante o dia. Na dosagem de 3,0 mg/Kg o pH mostrou-se ainda menos ácido (valor médio de pH=4,087), aproximando-se dos padrões requeridos de supressão ácida para tratamento de gastrites e úlceras gastroduodenais em seres humanos, além de apresentar valores mais estáveis do que nas semanas anteriores. Conclui-se que a dosagem de omeprazol de 3,0 mg/Kg foi a mais adequada para alcançar a supressão ácida desejada no tratamento das gastropatias.

Este trabalho teve por finalidade o desenvolvimento e validação de métodos para análise estereosseletiva de alguns fármacos e metabólitos, bem como a aplicação desses métodos na avaliação do potencial de fungos, principalmente endofíticos, em processos de biotransformação. Os seguintes fármacos foram selecionados para esse estudo: fluoxetina, propranolol, omeprazol, oxibutinina e ibuprofeno. Para determinação simultânea dos enantiômeros da fluoxetina (FLX) e norfluoxetina (NFLX) em meios de cultura de fungos endofíticos, empregou-se a cromatografia líquida de alta eficiência com detecção por absorção no ultravioleta, em um sistema com duas colunas em série, sendo uma de fase reversa (C18) e outra com fase estacionária quiral (Chirobiotic® V). A fase móvel foi composta por etanol: tampão acetato de amônio 15 mmol L-1, pH 5,90: acetonitrila (77,5: 17,5: 5, v/v/v) e a detecção foi realizada em 227 nm. A extração líquido-líquido foi empregada na preparação das amostras. As curvas analíticas foram lineares no intervalo de concentração de 12,5 a 3750 ng mL-1 (r 0,996) para todos os enantiômeros analisados. Os coeficientes de variação e erros relativos obtidos nos estudos de precisão e exatidão foram inferiores a 10%. Nas condições empregadas, os cinco fungos endofíticos estudados não foram capazes de promover a biotransformação da FLX (reação de demetilação). A eletroforese capilar foi empregada para análise enantiosseletiva do propranolol (PROP) e 4-hidroxipropranolol (4-OHPROP). A melhor condição de resolução dos enantiômeros foi encontrada com a aplicação de um planejamento experimental de Box-Behnken: solução de eletrólitos composta por tampão trietilamina / ácido fosfórico (TEA/H3PO4), 25 mmol L-1, pH 9,00, carboximetil--ciclodextrina 4% (m/v) como seletor quiral e análise realizada na voltagem de 17 kV. O método de extração líquido-líquido também foi empregado para preparação das amostras. As curvas analíticas foram lineares no intervalo de concentração de 0,25 a 10,0 g mL-1 para 4-OHPROP e de 0,10 a 10,0 g mL-1 para PROP, apresentando coeficientes de correlação (r) 0,995 para todos os enantiômeros analisados. Os coeficientes de variação e erros relativos obtidos nos estudos de precisão e exatidão foram inferiores a 15%. Os cinco fungos endofíticos em estudo se mostraram eficientes na biotransformação estereosseletiva do PROP, com maior formação do metabólito (-)-(S)-4-OHPROP. O fungo Glomerella cingulata (VA1), em especial, apresentou uma concentração de 1,745 g mL-1 do enantiômero (-)-(S)-4-OHPROP depois de 72 horas de incubação, ao passo que a formação do enantiômero (+)-(R)-4-OHPROP não foi observada. A utilização deste fungo em escalas ampliadas pode ser uma fonte promissora de obtenção do metabólito 4-OHPROP na forma enantiomericamente pura. A determinação simultânea de omeprazol (OMZ), 5-hidroxiomeprazol (5-HOMZ) e omeprazol sulfona (OMZ SUL) em meio de cultura Czapek Dox modificado ii tamponado foi realizada empregando um método rápido de análise por cromatografia líquida de ultra eficiência com detector por arranjo de diodos (UPLC / DAD), usando coluna monolítica de fase reversa e eluição por gradiente. OMZ, 5-HOMZ e OMZ SUL foram extraídos das amostras utilizando uma mistura de acetato de etila: t-butil metil éter (9: 1, v/v). A separação foi obtida empregando uma coluna RP 18 Chromolith Fast Gradient endcapped e fase móvel constituída por 0,15% (v/v) de ácido trifluoroacético (TFA) em água (solvente A) e 0,15% (v/v) de TFA em acetonitrila (solvente B). Os tempos de retenção foram de 0,70 min para 5-HOMZ, 0,74 min para OMZ, 0,77 min para OMZ SUL e 0,91 min para o padrão interno (bupropiona, BUP). O método foi linear no intervalo de 0,2 a 10,0 g mL-1 (r 0,995) para todos os analitos. O processo de biotransformação foi realizado durante apenas 24 horas de incubação, por causa de problemas de estabilidade do OMZ. Por esse mesmo motivo, a biotransformação estereosseletiva não foi avaliada. Apenas três fungos apresentaram formação do metabólito 5-HOMZ, e dentre estes, apenas o fungo Botritis cinerea (BC) produziu esse metabólito em concentração superior ao limite de quantificação do método. A formação do metabólito OMZ SUL foi observada para todos os fungos, exceto para Glomerella cingulata (VA1) e Guignardia mangiferae (VA15). Esses fungos podem ser úteis para a obtenção dos metabólitos do OMZ, mas estudos detalhados do comportamento do fármaco nas condições de cultivo são necessários, uma vez que este substrato pode sofrer degradação em meio ácido e na presença de luz. A análise simultânea dos enantiômeros da oxibutinina (OXY) e da N-desetiloxibutinina (DEOB) em meio de cultura Czapek foi obtida empregando a cromatografia líquida de alta eficiência com detector UV (HPLC/UV). Os analitos foram separados usando coluna quiral Chiralpak AD e fase móvel constituída por hexano: isopropanol: etanol: dietilamina (94: 4: 2: 0,05, v/v/v/v) e detectados em 210 nm. Um estudo piloto de biotransformação empregando os mesmos fungos e as condições de biotransformação utilizadas para os demais fármacos mostrou que não houve a formação do metabólito de interesse. Além disso, não houve uma diminuição significativa da concentração de OXY durante o período de incubação, o que poderia ser um indicativo da formação de outros metabólitos não monitorados nas condições de análise. Como a reação de desetilação da OXY para formar a DEOB não foi observada nos experimentos, não foi necessário realizar a validação do método analítico. A separação simultânea do ibuprofeno (IBP), dos enantiômeros do 2-hidroxi-ibuprofeno (2-OH-IBP) e dos estereoisômeros do carboxi-ibuprofeno (COOH-IBP) foi realizada empregando-se uma coluna Chiralpak AS-H e fase móvel constituída por hexano: isopropanol: TFA (95: 5: 0,1, v/v/v). O solvente extrator usado na extração líquido-líquido foi uma mistura de hexano: acetato de etila (1: 1, v/v). A detecção foi feita por espectrometria de massas (MS/MS), com a fonte de ionização por eletronebulização operada no modo positivo (ESI+). O método foi linear nos intervalos de 0,1 a 20,0 g mL-1 para IBP, de 0,05 a 7,5 g mL-1 para o cada enantiômero do 2-OH-IBP e de 0,025 a 5,0 g mL-1 para cada estereoisômero do COOH-IBP. Os demais parâmetros de validação obtidos para o método apresentaram-se dentro dos limites recomendados pela literatura. Os sete fungos endofíticos estudados se mostraram eficientes na biotransformação do IBP em seu principal metabólito 2-OH-IBP, mas apenas os fungos Nigrospora sphaerica (SS67) e Chaetomium globosum (VR10) iii biotransformaram o IBP de forma enantiosseletiva mais acentuada, observando-se maior formação do metabólito ativo (+)-(S)-2-OH-IBP. A não estereosseletividade observada para os demais fungos pode ser indício de uma possível conversão quiral do fármaco, similar a que ocorre em humanos. A formação dos estereoisômeros do COOH-IBP não foi observada, provavelmente, porque sua rota de formação envolve uma seqüência de reações. Os resultados apresentados nesse trabalho mostram que fungos, particularmente os endofíticos, podem ser uma fonte promissora para obtenção de metabólitos de fármacos, inclusive de forma enantiomericamente pura. / This work aimed the development and validation of suitable methods for the stereoselective analysis of some drugs and metabolites, as well as, the application of these methods to assess the potential of fungi, mainly the endophytic ones, in biotransformation processes. The following drugs were selected for this study: fluoxetine, propranolol, omeprazole, oxybutynin and ibuprofen. The simultaneous determination of fluoxetine (FLX) and norfluoxetine (NFLX) enantiomers in culture media of endophytic fungi was carried out by high-performance liquid chromatography with UV-detection, in a system of two columns coupled in series, in which one of them was a reversed phase (C18) column and the another one was a chiral stationary phase column (Chirobiotic ® V). The mobile phase consisted of ethanol: ammonium acetate buffer, 15 mol L-1, pH 5.90: acetonitrile (77.5: 17.5: 5, v/v/v) and the detection was performed at 227 nm. Liquid-liquid extraction was employed for sample preparation. The analytical curves were linear over the concentration range of 12.5 to 3750 ng mL-1 (r 0.996) for all enantiomers evaluated. The coefficients of variation and relative errors obtained in the evaluation of method precision and accuracy were lower than 10%. In the studied conditions, the five endophytic fungi used were not able to perform the biotransformation of FLX (demethylation reaction). Capillary electrophoresis was employed for the enantioselective analysis of propranolol (PROP) and 4-hydroxypropranolol (4-OHPROP). The best condition for enantiomer resolution was obtained by applying an experimental design of Box-Behnken: electrolyte solution composed of triethylamine / phosphoric acid (TEA/H3PO4) buffer, 25 mmol L-1, pH 9.00, with 4% (w/v) carboxymethyl--cyclodextrin as the chiral selector and analysis performed at 17 kV. Liquid-liquid extraction was also used for sample preparation. The analytical curves were linear over the concentration range of 0.25 to 10.0 g mL-1 for 4-OHPROP and 0.10 to 10.0 g mL-1 for PROP, presenting correlation coefficients (r) 0.995 for all enantiomers evaluated. The coefficients of variation and relative errors obtained in the evaluation of precision and accuracy were lower than 15%. All the five endophytic fungi (Phomopsis sp. (TD2), Glomerella cingulata (VA1), Penicillium crustosum (VR4), Chaetomium globosum (VR10) and Aspergillus fumigatus (VR12)) showed effectiveness in the stereoselective biotransformation of PROP, with higher formation of (-)-(S)-4-OH-PROP. The fungus Glomerella cingulata (VA1), in particular, showed a concentration of 1.745 g mL-1 for the enantiomer (-)-(S)-4-OHPROP after 72 hours of incubation, whereas there was no formation of the enantiomer (+)-(R)-4-OHPROP. Therefore, the use of this fungus in large scale may be a promising source to obtain 4-OHPROP in the enantiomerically pure form. A fast analytical method based on ultra-performance liquid chromatography / diode array detector (UPLC/DAD) using a monolithic reversed phase column and gradient elution was developed for the simultaneous determination of omeprazole (OMZ), 5-hydroxyomeprazole (5-HOMZ) and omeprazole sulfone (OMZ SUL) in modified and buffered Czapek-Dox culture medium. OMZ, 5-HOMZ and OMZ SUL were extracted using a mixture of ethyl acetate: methyl t-butyl ether (9: 1, v/v). The separation was achieved using a Chromolith Fast Gradient RP 18 endcapped column with the mobile phase consisting of 0.15% (v/v) trifluoroacetic acid (TFA) in water (solvent A) and 0.15% (v/v) TFA in acetonitrile (solvent B). Retention times were 0.70 min for 5-HOMZ, 0.74 min for OMZ, 0.77 min for OMZ SUL and 0.91 min for internal standard (bupropion, BUP). The method was linear over the concentration range of 0.2 to 10.0 g mL-1 (r 0.995) for all analytes. The biotransformation process was carried out only within 24 hours of incubation, due to OMZ instability. For the same reason, the stereoselectivity in this process was not evaluated. The formation of the metabolite 5-HOMZ was observed only for three fungi, and among them, only the fungus Botrytis cinerea (BC) produced this metabolite in concentrations higher than the limit of quantification. The formation of OMZ SUL was observed for all fungi, except for Guignardia mangiferae (VA1) and Glomerella cingulata (VA15). The fungi evaluated in this study can be useful to obtain the metabolites of OMZ, but detailed study of the drug stability in culture conditions is required, since this substrate can undergo degradation in acidic conditions and in the presence of light. The simultaneous analysis of oxybutinin (OXY) and N-desethyloxybutinin (DEOB) enantiomers in Czapek culture medium was carried out by liquid chromatography with UV detection (HPLC/UV). The analytes were separated using a Chiralpak AD column employing as mobile phase hexane: isopropanol: ethanol: diethylamine (94: 4: 2: 0.05, v/v/v/v) and detection at 210 nm. A pilot study of biotransformation using the same fungi and conditions employed for the biotransformation of the other drugs showed that the metabolite of interest was not formed. Moreover, the decrease in the concentration of OXY, which could be indicative of the formation of other metabolites not monitored under the conditions of analysis, was not observed. Since the reaction of OXY desethylation to form DEOB was not observed in the experiments, the validation of the analytical method was not required. The method for the simultaneous analysis of ibuprofen (IBP), 2-hydroxyibuprofen (2-OH-IBP) enantiomers and carboxyibuprofen (IBP-COOH) stereoisomers was developed using a Chiralpak AS-H column and a mobile phase consisting of hexane: isopropanol: TFA (95: 5: 0.1, v/v/v). A mixture of hexane: ethyl acetate (1: 1, v/v) was used as solvent extractor for sample preparation. The detection was performed by tanden mass spectrometry (MS/MS) with the electrospray interface operated in the positive mode (ESI+). The method was linear over the concentration range of 0.1 to 20.0 g mL-1 for IBP, 0.05 to 7.5 g mL-1 for each 2-OH-IBP enantiomer and 0.025 to 5.0 g mL-1 for each COOH-IBP stereoisomer. The other validation parameters studied were within the limits established in the literature. The seven studied endophytic fungi showed to be efficient in the biotransformation of IBP to its main metabolite 2-OH-IBP, however, only the fungi Nigrospora sphaerica (SS67) and Chaetomium globosum (VR10) biotransformed IBP enantioselectively, with greater formation of the active metabolite (+)-(S)-2-OH-IBP. The lack of stereoselectivity observed for the other fungi could be caused by a possible chiral inversion process occurring for IBP, in a similar way that happens in humans. The formation of COOH-IBP stereoisomers was not observed probably because the route of formation of this metabolite requires a sequence of reactions. The results presented here show that fungi, particularly the endophytic ones, may be a promising source to obtain the metabolites of drugs, including in their enantiomerically pure form.