Objective: To explore consumer attitudes towards generic medication. Methods: A quantitative method was used in this explorative study to assess consumer attitudes towards generic medication. A survey design was utilized. A questionnaire was devised that comprised four sections which assessed attitudes towards generic medication. A Living Standards Measure (LSM) assessed socio-economic status. Convenience sampling resulted in the recruitment of 266 respondents. Statistical analysis of the data included non-parametric (Chi-square and correlation analysis) and parametric statistics (factor analysis, MANOVA and regression analysis). Results: More than half the respondents (54.8%) report preference for original medication over generic medication. A large percentage believes there is a place for generic medication (88.9%). The majority (95%) indicate they would purchase generic medication if it proves to be just as effective as the original product. More respondents (91.2%) trust physician over pharmacist recommendations to purchase generics. More than half the respondents (57.9%) would purchase generic medication if recommended by friends but they trust their family members more (68.6%). The findings indicate that respondents generally hold favourable attitudes towards the efficacy of generic medication despite the fact that slightly more than half prefer original medication. Respondents indicate that pricing and branding influence their attitudes towards generic medication. Chi-square analyses indicated that more men would choose original medication and more women would choose generic medication. Age differences revealed that the older consumer is more likely to choose generic medication. White respondents indicated a preference for generic medication, while Black respondents indicated that they prefer original medication. Middle-class (LSM 5-8) and middle-upper class (LSM 9) respondents prefer generic medication, while upper class (LSM 10) respondents prefer original medication. The correlation analysis found no significant relationship between medical aid status and original or generic medication choice. A principle component factor analysis produced nine factors based on the items in the questionnaire, with only eight factors being subjected to further testing. These eight factors were subjected to a MANOVA and tested against gender and race with no significant differences found between men and women and between Black and White respondents. These eight factors were also subjected to further testing by means of regression analysis where it was found that three of the eight factors were statistically significant. These three factors can be productively explored in future research. Implications: This explorative study focused on consumer attitudes towards generic medication, however, it was identified that the consumer valued their physician’s recommendation for type of medication. For future studies, it would be beneficial to explore medical personnel (physician and pharmacist) attitudes towards generic medication as these individuals play an important role in product choice. Copyright / Dissertation (MA)--University of Pretoria, 2012. / Psychology / unrestricted

Lamivudina (3TC) e zidovudina (ZDV) são inibidores nucleosídeos da transcriptase reversa utilizados na terapêutica anti-HIV. Para avaliar a equivalência farmacêutica entre um medicamento teste contendo esta associação e o referência, foi desenvolvido um método para determinação cromatográfica simultânea de 3TC e ZDV em comprimidos. O método empregou coluna C8 Shim-pack®(150 x 4,6 mm, 5 µm), pré-coluna C18 Phenomenex® (50x4,6 mm 5um), água e metanol 60:40 (v:v) como fase móvel e detecção a 266nm. Este mostrou-se específico, com linearidade entre 45 a 5000 ng/mL, precisão demonstrada por CV% inferior a 5%, exatidão entre 90,0 e 110,0% com recuperação superior a 90% para ambos os fármacos. Os testes de dissolução apresentaram porcentagem de cedência média superior a 85% em 30 minutos. A biodisponibilidade relativa dos produtos Biovir® (referência) e Lamivudina + Zidovudina 150 + 300 mg (teste), foi avaliada por meio de um estudo quantitativo direto, cruzado e aberto. Para purificação das amostras biológicas contendo 3TC e ZDV foi realizada adição de acetato de amônio e dupla extração com acetato de etila. O método cromatográfico bioanalítico utilizou coluna C8 Shim-pack® (150 x 4,6 mm 5 µm) e pré-coluna C18 Phenomenex® (50 x 4,6 mm; 5 µm). Empregou-se sistema gradiente linear, combinando fase móvel A, tampão fosfato 0,01 M:acetonitrila (97:3 v/v) e fase móvel B, metanol, sob fluxo de 1,0 mL/min e detecção a 270 nm. Utilizou-se como padrão interno solução 10 µg/mL de estavudina. O método mostrou-se linear na faixa de concentração de 80 a 2500 ng/mL para 3TC e 80 a 5000 ng/mL para ZDV, com adequada precisão e exatidão intra-corridas e inter-corridas. As amostras plasmáticas mostraram-se estáveis a pelo menos três ciclos de congelamento e descongelamento e 48 horas à temperatura ambiente, após preparação. Os parâmetros farmacocinéticos calculados para 3TC foram: ASCo-t de 4936,10 ng.h/mL e 4760,07 ng.h/mL, ASCo-∞ de 5305,76 ng.h/mL e 5069,16 ng.h/mL; Cmax de 1526,33 ng/mL e 1585,61 ng/mL e tmax 1,04 h e 0,97 h, respectivamente, para os produtos referência e teste. Para ZDV os valores obtidos foram ASCo-t de 2341,32 ng.h/mL e 2538,17 ng.h/mL, ASCo-∞ de 2561,68 ng.h/mL e 2770,21 ng.h/mL e Cmax de 2406,56 ng/mL e 2652,80 ng/mL e tmax 0,60 h e 0,55 h, respectivamente, para os produtos referência e teste. Os intervalos de confiança 90% para as relações entre os parâmetros Cmax, ASCo-t e ASCo-∞ em escala logarítmica obtidos para ambos os fármacos após administração dos produtos referência e teste a 24 voluntários sadios, estiveram compreendidos entre os limites de 80 a 125% exceto pelo Cmax para ZDV. O coeficiente de variação intra-sujeito de 47% demonstrou a alta variabilidade da ZDV em relação ao Cmax. Estudos de permeabilidade indicaram que a ZDV tem alta permeabilidade e alta solubilidade (Classe I) e a 3TC apresenta moderada permeabilidade e alta solubilidade (Classe III) . A absorção destes não é afetada significativamente pelas glicoproteínas-P, o que não pode explicar a alta variabilidade in vivo da absorção de ZDV. / Lamivudine (3TC) and zidovudine (ZDV) are the nucleoside reverse transcriptase inhibitors, They are used in combinations of antiretroviral therapy. The switchability between one test product and reference could be proved if they are pharmaceutically equivalents and bioequivalents. This research beginning with development and validation of chromatographic method to 3TC and ZDV simultaneous determination in tablet. The HPLC system were used to assay and 266nm wavelength ultraviolet detector. Separation was performed using a C8 column (150 x 4,6 mm, 5 µm) Shim-pack®protected by a C18 column (50 x 4,6 mm, 5 µm) Phenomenex®. The mobile phase is composed of water and methanol 60:40 (v:v). This method was successfully applied to simultaneous determination to 3TC and ZDV without interference. It was validated over the range of 45 a 5000 ng/mL for both drugs with accurate from 90 to 110% and precision with variation lower than 5%. Extraction recoveries of the analytes were higher than 90%. The mean dissolution data about 3TC and ZDV were above than 85% in 30 minutes of dissolution test. The relative bioavailability between Biovir® (brand-name product) and Lamivudina + Zidovudina 150 + 300 mg (test product), was conducted for one direct quantitative, open and crossover study. The serial plasma sample of 3TC and ZDV collected after oral administration of brand-name product and test product, were analyzed using a validated high-performance liquid chromatography assay with UV detection in wavelength of 270 nm. The double liquid-liquid extraction was realized with additions of amonio acetat. A CLC-C8 (M) column (150 x 4,6 mm 5 µm) Shim-pack®and C18 column (50 x 4,6mm 5 µm) Phenomenex®, was eluted with two mobile phase in a linear gradient system at a flow-rate of 1 mL/min. The mobile phase A was composed by 0,01 M phosphate bufer:acetonitrile (97:3 v/v) and mobile phase B composed by methanol. A methanolic solution containing 10 µ g/mL of stavudine was used as internai standard. The method was linear over the range of 80 a 2500 ng/mL for 3TC and 80 a 5000 ng/mL for ZDV. It was shown adequate intra-day accuracy; inter-day accuracy and precision. The sample have been stable in three cycle of freezing and thawing and 48 hours in room temperature after thawing, purified and with mobile phase. The pharmacokinetic parameter estimates for 3TC, were: ASCo-t de 4936,10 ng.h/mL e 4760,07 ng.h/mL, ASCo-C/) de 5305,76 ng.h/mL e 5069,16 ng.h/mL; Cmax de 1526,33 ng/mL e 1585,61 ng/mL e tmax 1,04 h e 0,97 h, respectively for brand-name product and test product. The obtained values for ZDV were: ASCo-t de 2341 ,32 ng.h/mL e 2538,17 ng.h/mL, ASCo-if.l de 2561,68 ng.h/mL e 2770,21 ng.h/mL e Cmax de 2406,56 ng/mL e 2652,80 ng/mL e tmax 0,60 h e 0,55 h respectively for for brand-name product and test product. The 90% confidence intervals for Cmax, ASCo-t e ASCo-∞ for log¬transformed results for 3TC and ZDV after oral administration of brand-name product and test product to 24 health volunteers was between 80 to 125% except for Cmax of ZDV. The high variability of Cmax this was displayed by intra-individual coefficient of variation of 47%. Permeability results suggest that ZDV has a high permeability and high solubility (Class I) and Lamivudine presents moderate permeability and high solubility. (Class III). These results assume that P-gp do not affect significantly lamivudine and zidovudine absorption and can not explain the high variability of zidovudine absorption.

Lamivudina (3TC) e zidovudina (ZDV) são inibidores nucleosídeos da transcriptase reversa utilizados na terapêutica anti-HIV. Para avaliar a equivalência farmacêutica entre um medicamento teste contendo esta associação e o referência, foi desenvolvido um método para determinação cromatográfica simultânea de 3TC e ZDV em comprimidos. O método empregou coluna C8 Shim-pack®(150 x 4,6 mm, 5 µm), pré-coluna C18 Phenomenex® (50x4,6 mm 5um), água e metanol 60:40 (v:v) como fase móvel e detecção a 266nm. Este mostrou-se específico, com linearidade entre 45 a 5000 ng/mL, precisão demonstrada por CV% inferior a 5%, exatidão entre 90,0 e 110,0% com recuperação superior a 90% para ambos os fármacos. Os testes de dissolução apresentaram porcentagem de cedência média superior a 85% em 30 minutos. A biodisponibilidade relativa dos produtos Biovir® (referência) e Lamivudina + Zidovudina 150 + 300 mg (teste), foi avaliada por meio de um estudo quantitativo direto, cruzado e aberto. Para purificação das amostras biológicas contendo 3TC e ZDV foi realizada adição de acetato de amônio e dupla extração com acetato de etila. O método cromatográfico bioanalítico utilizou coluna C8 Shim-pack® (150 x 4,6 mm 5 µm) e pré-coluna C18 Phenomenex® (50 x 4,6 mm; 5 µm). Empregou-se sistema gradiente linear, combinando fase móvel A, tampão fosfato 0,01 M:acetonitrila (97:3 v/v) e fase móvel B, metanol, sob fluxo de 1,0 mL/min e detecção a 270 nm. Utilizou-se como padrão interno solução 10 µg/mL de estavudina. O método mostrou-se linear na faixa de concentração de 80 a 2500 ng/mL para 3TC e 80 a 5000 ng/mL para ZDV, com adequada precisão e exatidão intra-corridas e inter-corridas. As amostras plasmáticas mostraram-se estáveis a pelo menos três ciclos de congelamento e descongelamento e 48 horas à temperatura ambiente, após preparação. Os parâmetros farmacocinéticos calculados para 3TC foram: ASCo-t de 4936,10 ng.h/mL e 4760,07 ng.h/mL, ASCo-∞ de 5305,76 ng.h/mL e 5069,16 ng.h/mL; Cmax de 1526,33 ng/mL e 1585,61 ng/mL e tmax 1,04 h e 0,97 h, respectivamente, para os produtos referência e teste. Para ZDV os valores obtidos foram ASCo-t de 2341,32 ng.h/mL e 2538,17 ng.h/mL, ASCo-∞ de 2561,68 ng.h/mL e 2770,21 ng.h/mL e Cmax de 2406,56 ng/mL e 2652,80 ng/mL e tmax 0,60 h e 0,55 h, respectivamente, para os produtos referência e teste. Os intervalos de confiança 90% para as relações entre os parâmetros Cmax, ASCo-t e ASCo-∞ em escala logarítmica obtidos para ambos os fármacos após administração dos produtos referência e teste a 24 voluntários sadios, estiveram compreendidos entre os limites de 80 a 125% exceto pelo Cmax para ZDV. O coeficiente de variação intra-sujeito de 47% demonstrou a alta variabilidade da ZDV em relação ao Cmax. Estudos de permeabilidade indicaram que a ZDV tem alta permeabilidade e alta solubilidade (Classe I) e a 3TC apresenta moderada permeabilidade e alta solubilidade (Classe III) . A absorção destes não é afetada significativamente pelas glicoproteínas-P, o que não pode explicar a alta variabilidade in vivo da absorção de ZDV. / Lamivudine (3TC) and zidovudine (ZDV) are the nucleoside reverse transcriptase inhibitors, They are used in combinations of antiretroviral therapy. The switchability between one test product and reference could be proved if they are pharmaceutically equivalents and bioequivalents. This research beginning with development and validation of chromatographic method to 3TC and ZDV simultaneous determination in tablet. The HPLC system were used to assay and 266nm wavelength ultraviolet detector. Separation was performed using a C8 column (150 x 4,6 mm, 5 µm) Shim-pack®protected by a C18 column (50 x 4,6 mm, 5 µm) Phenomenex®. The mobile phase is composed of water and methanol 60:40 (v:v). This method was successfully applied to simultaneous determination to 3TC and ZDV without interference. It was validated over the range of 45 a 5000 ng/mL for both drugs with accurate from 90 to 110% and precision with variation lower than 5%. Extraction recoveries of the analytes were higher than 90%. The mean dissolution data about 3TC and ZDV were above than 85% in 30 minutes of dissolution test. The relative bioavailability between Biovir® (brand-name product) and Lamivudina + Zidovudina 150 + 300 mg (test product), was conducted for one direct quantitative, open and crossover study. The serial plasma sample of 3TC and ZDV collected after oral administration of brand-name product and test product, were analyzed using a validated high-performance liquid chromatography assay with UV detection in wavelength of 270 nm. The double liquid-liquid extraction was realized with additions of amonio acetat. A CLC-C8 (M) column (150 x 4,6 mm 5 µm) Shim-pack®and C18 column (50 x 4,6mm 5 µm) Phenomenex®, was eluted with two mobile phase in a linear gradient system at a flow-rate of 1 mL/min. The mobile phase A was composed by 0,01 M phosphate bufer:acetonitrile (97:3 v/v) and mobile phase B composed by methanol. A methanolic solution containing 10 µ g/mL of stavudine was used as internai standard. The method was linear over the range of 80 a 2500 ng/mL for 3TC and 80 a 5000 ng/mL for ZDV. It was shown adequate intra-day accuracy; inter-day accuracy and precision. The sample have been stable in three cycle of freezing and thawing and 48 hours in room temperature after thawing, purified and with mobile phase. The pharmacokinetic parameter estimates for 3TC, were: ASCo-t de 4936,10 ng.h/mL e 4760,07 ng.h/mL, ASCo-C/) de 5305,76 ng.h/mL e 5069,16 ng.h/mL; Cmax de 1526,33 ng/mL e 1585,61 ng/mL e tmax 1,04 h e 0,97 h, respectively for brand-name product and test product. The obtained values for ZDV were: ASCo-t de 2341 ,32 ng.h/mL e 2538,17 ng.h/mL, ASCo-if.l de 2561,68 ng.h/mL e 2770,21 ng.h/mL e Cmax de 2406,56 ng/mL e 2652,80 ng/mL e tmax 0,60 h e 0,55 h respectively for for brand-name product and test product. The 90% confidence intervals for Cmax, ASCo-t e ASCo-∞ for log¬transformed results for 3TC and ZDV after oral administration of brand-name product and test product to 24 health volunteers was between 80 to 125% except for Cmax of ZDV. The high variability of Cmax this was displayed by intra-individual coefficient of variation of 47%. Permeability results suggest that ZDV has a high permeability and high solubility (Class I) and Lamivudine presents moderate permeability and high solubility. (Class III). These results assume that P-gp do not affect significantly lamivudine and zidovudine absorption and can not explain the high variability of zidovudine absorption.