O paciente grande queimado está entre os de maior risco de contrair infecção hospitalar, sendo que, aproximadamente 80% dos óbitos nestes pacientes são decorrentes de infecção. Devido à prevalência de S. aureus meticilina resistente (MRSA) nas unidades de queimados prescreve-se a vancomicina como fármaco de 1ª linha. Entretanto como a farmacocinética se encontra profundamente alterada geralmente ocorre a falência terapêutica e surgimento de resistência antimicrobiana. O objetivo do presente estudo foi monitorar as concentrações plasmáticas através da análise em CLAE-UV e realizar a modelagem farmacocinética da vancomicina, administrada nestes pacientes. Para tanto, validou-se método analítico que se mostrou linear, preciso, exato e suficientemente sensível para o monitoramento das concentrações plasmáticas da vancomicina nos pacientes. Investigaram-se 9 pacientes adultos grandes queimados após cirurgia de debridamento; os pacientes foram informados em detalhes sobre o estudo e assinaram o TCLE, e incluídos no protocolo. Coletaram amostras sangüíneas seriadas para a farmacocinética (PK solutions 2.0). A estatística descritiva (Microsoft Excell, Office for Windows, versão 2000) forneceu os resultados expressos através da média +/- DP: 16 mg/L±11, para o pico (referência 20-40mg/L) e 2,6 mg/L±1,5 para o vale (referência,5-10mg/L), abaixo da CME nestes pacientes. Os parâmetros farmacocinéticos foram o volume aparente de distribuição que se mostrou aumentado em cerca de 3,5 vezes, (1,4 L/Kg ± 0,8 versus 0,33-0,45L/kg, referência, a depuração plasmática mostrou-se aumentada em cerca de 2,5 vezes (3,2±1,65 mL/min.kg versus 1,3 - 1,5mL/min.kg, referência, enquanto a constate de eliminação e a meia-vida biológica se mantiveram inalteradas. Este estudo indica que o regime posológico e tipo de infusão endovosa devam ser revistos, utilizando a farmacocinética como ferramenta importante. Recomenda-se ainda que a terapia dose ajustada seja baseada no controle terapêutico destes pacientes em todas as fases da internação, principalmente após cada cirurgia de debridamento. / Nosocomial infections shows high incidence in burn patient, and approximately 80% of mortality of them is due to severe infections and sepse. High prevalence of methycilin resistant S. aureus (MRSA) occurs in the intensive care units for burn patients and vancomycin is largely prescribed as first choice drug for severe infections and sepse. In general occurs therapeutic fail, since the pharmacokinetics is altered in these patients and arise the antimicrobial resistance. The main of the present study was to perform therapeutic plasma vancomycin monitoring by HPLC-UV and also PK- modelling after 1g every 12 hours, 1 hour infusion. Bioanalitical method was validated showing good linearity, precision, accuracy, good stability and robustness. Additionally method required 200µL of plasma and showed sensitivity enough for vancomycin plasma monitoring. Nine large burn patients were included in the study after they signed the informed written consent term to participate of the protocol. The follow up was done after debridment surgery. Blood samples were collected from venous catheter at time dose interval to investigate the pharmacokinetics (PK solutions 2.0) and also to determine the peak and trough. Descriptive statistics was performed applying Microsoft Excell, Office for Windows, versão 2000. Data obtained were 16 mg/L±11 peak (reference 20-40mg/L) and 2.6 mg/L±1.5 trough that was lower than MEC since the reference ranges from 5 to 10mg/L). Pharmacokinetic parameters were volume apparent of distribution, that was increased by 3.5 times (1.4 L/Kg ± 0,8 against the reference values 0.33-0.45L/kg), plasma clearance was also increased by 2.5 times (3.2±1.7mL/min.kg versus 1.3 - 1.5mL/min.kg, reference values), while elimination rate constant and biological half-life remained unchanged in those patients. Based on data obtained in the study, author recommends a revision on dose schedule and also concerning intravenous drug infusion using the pharmacokinetics as a powerful tool and the therapeutic plasma vancomycin monitoring for dose adjustments in all phases of the follow up of burn patient, mainly after each surgery debridement.

HIV antiretroviral therapy spans several different drug classes, meant to combat various aspects of viral infection and replication. Many authors have argued the benefits of therapeutic drug monitoring (TDM) for the HIV patient including compliance assurance and assessment of appropriate drug concentrations; however, the array of drug chemistries and combinations makes TDM an arduous task. HPLC-UV and LC-MS/MS are both frequent instruments for the quantification of HIV drugs in biological matrices with investigators striving to balance sensitivity and affordability. Plasma, the dominant matrix for these analyses, is prepared using protein precipitation, liquid-liquid extraction or solid-phase extraction depending on the specific complement of analytes. Despite the range of polarities found in drug classes relevant to HIV therapeutics, most chromatographic separations utilize a hydrophobic column (C18 ). Additionally, as the clinically relevant samples for these assays are infected with HIV, along with possible co-infections, another important aspect of sample preparation concerns viral inactivation. Although not routine in clinical practice, many published analytical methods from the previous two decades have demonstrated the ability to conduct TDM in HIV patients receiving various medicinal combinations. This review summarizes the analytical methods relevant to TDM of HIV drugs, while highlighting respective challenges.

Dans la pratique courante, la posologie des anticancéreux est le plus souvent normalisée parrapport à la surface corporelle du patient (parfois son poids). Cependant, cette adaptation de dose neprend pas en compte la variabilité interindividuelle pharmacologique du médicament. Les facteursmodulant cette dernière sont nombreux, dont notamment les capacités individuelles de métabolisme etd’élimination. A dose égale, l’exposition systémique du patient peut donc varier, et entraîner un risquede surdosage pour certains patients, avec la survenue de toxicités, ou de sous-dosage pour d’autres,associée à une limitation de l’efficacité thérapeutique. Des alternatives à l’utilisation de la surfacecorporelle ont donc été proposées afin de prendre en compte de façon plus importante la variabilitéinterindividuelle des patients, tel que le suivi thérapeutique pharmacologique ou lapharmacogénétique. Les polymorphismes des gènes codants pour des enzymes impliquées dans lemétabolisme ou le transport des cytotoxiques peuvent modifier leur activité et donc influer sur lapharmacocinétique d’un médicament donné. Le développement des connaissances dans ces domainespourrait permettre la mise en place, de façon progressive, de nouvelles méthodes d’ajustement de laposologie.Ce projet de thèse porte sur l’individualisation de la posologie des anticancéreux ens’intéressant aussi bien aux chimiothérapies cytotoxiques, avec pour modèle l’irinotecan, qu’auxthérapies ciblées, en distinguant dans cette même classe les inhibiteurs de tyrosine kinase et lesanticorps monoclonaux (modèle du bévacizumab). Afin d’optimiser l’index thérapeutique de cestraitements, l’adaptation de la posologie a été abordée selon le profil pharmacogénétique maiségalement selon le profil pharmacocinétique.Une étude clinique a été mise en place afin d’évaluer, en terme de toxicité et d’efficacité,l’intérêt d’une adaptation de posologie de l’irinotécan dans le cadre d’une polychimiothérapie dans letraitement du cancer colorectal (FOLFIRI +/- bévacizumab ou cétuximab), en se basant sur unpolymorphisme génétique de l’UGT1A1, enzyme impliquée dans son métabolisme. Les résultats del’étude intermédiaire de cet essai de phase II, mené chez 16 patients, sont en faveur de la poursuite del’étude avec 12,5% de toxicités hématologiques de grade 4 et un taux de réponse objective de 58,3 %.L’objectif secondaire a été l’étude de la pharmacocinétique de l’irinotécan et de ses métabolites lorsd’une des cures de chimiothérapie. Ces dosages ont été réalisés par chromatographie liquide couplée àla spectrométrie de masse. Cette technique, largement utilisée pour la quantification plasmatique desmédicaments, a été développée et validée selon les normes en vigueur. Le dosage du bévacizumab, unanticorps monoclonal associé au FOLFIRI dans le traitement du cancer colorectal, a lui aussi étédéveloppé par cette technique et a fait l’objet d’un travail de mise au point avec l’identification despeptides spécifiques, ainsi que l’optimisation des étapes de prétraitement de l’échantillon et de latechnique analytique.En parallèle, la mise en place du dosage des inhibiteurs de tyrosine kinase par spectrométrie demasse, ainsi que sa validation, ont fait partie de ce travail de thèse, et autorisent son utilisation enroutine hospitalière dans le cadre du suivi thérapeutique pharmacologique.Mots-clés : suivi thérapeutique pharmacologique, pharmacogénétique, irinotécan, chromatographie / Usually, the dosage of anticancer is normalized with used to the patient's body surface area(sometimes its weight). However, this adaptation does not take into account the interindividualpharmacological variability in the pharmacokinetics of the drug. Factors modulating thispharmacokinetics are numerous, including interindividual capacities of metabolism and elimination.At the same dosage, the systemic exposure of the patient can thus be changed, and cause a risk ofoverdosing for some patients, with the development of toxicities, or under dosing for others, withlimiting the therapeutic efficacy. Alternatives to the use of the body surface area have been proposedin order to more take account of inter-individual variability of patients, such as therapeutic drugmonitoring or pharmacogenetics. Genetic polymorphisms of enzymes involved in the metabolism ortransport of a cytotoxic, can change and modify their activity, and impact on drug’s metabolism. Thedevelopment of knowledge in these areas could allow the establishment of new methods to dosage’sadjustment.This PhD project focuses on individualizing dosage of anticancer focusing in both cytotoxicchemotherapies with the model of irinotecan, as targeted therapies, distinguishing in this same classtyrosine kinase inhibitors and monoclonal antibodies (bevacizumab model). To optimize thetherapeutic index of these therapies, the dose adjustment was according to pharmacogenetics profile,but also according to the pharmacokinetics profile.A clinical study was developed to studying, in terms of toxicity and efficacy, the interest ofadapting dosage of irinotecan in combination of chemotherapy to traitement of metastatic colorectalcancer (FOLFIRI +/- bevacizumab or cetuximab), based on a genetic polymorphism of UGT1A1, anenzyme involved in its metabolism. Results of the interim study of this phase II trial, conducted in 16patients, are in favor of study continuation with 12.5% grade 4 hematological toxicities, and objectiveresponse rate of 58.3%. The secondary objective was to study the pharmacokinetics of irinotecan andits metabolites during one cycle. These assays were performed by liquid chromatography-massspectrometry. This technique, widely used for quantification of drug in plasma was developed andvalidated according to standards. The dosage of bevacizumab, a monoclonal antibody used tocolorectal cancer treatment (associated to FOLFIRI) was also developed by this technique, withspecific peptide identification, and optimization of sample preparation and analytical technique.In parallel, the implementation of the determination of tyrosine kinase inhibitors by massspectrometry and its validation were part of this PhD project, and allow its use in hospital routine intherapeutic drug monitoring.

<p>Non-adherence to medication is a major obstacle in the treatment of depression. The objectives of the present study were to explore the effect of two interventions aiming to increase antidepressant treatment adherence, and to examine long-term consequences and costs of depression in adherent and non-adherent primary care patients. </p><p>A randomised controlled design was used to assess the respective effects of a written educational adherence enhancing programme and therapeutic drug monitoring in patients with major depression treated with sertraline for 24 weeks. All patients were prospectively followed during two years. </p><p>Treatment adherence was found in 41% of the 1031 included patients. None of the interventions resulted in a significant increase in adherence rate. However, significantly more patients in the group receiving the written educational material had responded at week 24 as compared to patients in the control group. </p><p>The overall remission rate after two years was 68%. In total, 34% of the responders experienced at least one relapse. Response and remission rates at week 24, year 1 and year 2 were significantly higher in adherent as compared to non-adherent patients. No relationship between adherence and relapse rate was seen. </p><p>The mean total cost per patient during two years was KSEK 363 whereof indirect costs represented 87%. No significant differences in costs between intervention groups or between adherent and non-adherent patients could be demonstrated. However, the mean cost per patient was 39% lower for treatment responders as compared to non-responders. </p><p>Non-adherence was predicted by age below 35 or above 64 years, no concomitant medications, personality disorder, sensation seeking personality traits and substance abuse. </p><p>The results indicate a strong positive relationship between treatment adherence and clinical outcome. In addition, the study shows that depression is a costly disease and that certain patient characteristics predict non-adherence.</p>

Non-adherence to medication is a major obstacle in the treatment of depression. The objectives of the present study were to explore the effect of two interventions aiming to increase antidepressant treatment adherence, and to examine long-term consequences and costs of depression in adherent and non-adherent primary care patients. A randomised controlled design was used to assess the respective effects of a written educational adherence enhancing programme and therapeutic drug monitoring in patients with major depression treated with sertraline for 24 weeks. All patients were prospectively followed during two years. Treatment adherence was found in 41% of the 1031 included patients. None of the interventions resulted in a significant increase in adherence rate. However, significantly more patients in the group receiving the written educational material had responded at week 24 as compared to patients in the control group. The overall remission rate after two years was 68%. In total, 34% of the responders experienced at least one relapse. Response and remission rates at week 24, year 1 and year 2 were significantly higher in adherent as compared to non-adherent patients. No relationship between adherence and relapse rate was seen. The mean total cost per patient during two years was KSEK 363 whereof indirect costs represented 87%. No significant differences in costs between intervention groups or between adherent and non-adherent patients could be demonstrated. However, the mean cost per patient was 39% lower for treatment responders as compared to non-responders. Non-adherence was predicted by age below 35 or above 64 years, no concomitant medications, personality disorder, sensation seeking personality traits and substance abuse. The results indicate a strong positive relationship between treatment adherence and clinical outcome. In addition, the study shows that depression is a costly disease and that certain patient characteristics predict non-adherence.

Durant la dernière décennie, les inhibiteurs de tyrosine kinases (ITK) ont radicalement changé l’évolution de certains cancers comme la leucémie myéloïde chronique (LMC) ou les tumeurs stromales gastro-intestinales (GIST). Ils sont aujourd’hui largement utilisés dans le traitement de diverses pathologies malignes, permettant un allongement de la survie globale. Cependant, certains patients ne montrent pas d’amélioration au cours du traitement par ITK. Les mécanismes évoqués sont multifactoriels et possèdent une origine pharmacocinétique, pharmacodynamique ou pharmacogénétique. En effet, l’une des causes majeures de variabilité commune à tous ces ITK réside dans un métabolisme impliquant le cytochrome 3A4, dont l’expression est soumise à de nombreux facteurs. L’objectif de cette thèse a été d’approfondir ces mécanismes et d’évaluer certaines stratégies afin d’augmenter l’efficacité de ces médicaments. Ce travail a consisté en premier lieu à développer une méthode chromatographique sensible et rapide permettant le dosage de neufs ITK commercialisés ou en phase avancée de développement. Cet outil, à la base du suivi thérapeutique pharmacologique, a été utilisé dans le cadre de la LMC pour mesurer les concentrations plasmatiques d’imatinib de plus de 3000 patients. Les informations cliniques de ces patients ont été saisies dans une base de données servant de support à l’évaluation de la réponse en fonction de la concentration. Nous avons ainsi confirmé que les patients présentant des concentrations supérieures au seuil d’efficacité de 1000 ng/mL avaient une plus grande probabilité de réponse. Dans la continuité de ce projet, nous avons évalué la relation concentration-efficacité de l’imatinib dans les GIST et trouvé un seuil d’efficacité voisin de 800 ng/mL. Tous les facteurs de variabilités ne sont cependant pas maitrisables avec un dosage plasmatique. La littérature rapporte en effet que certains ITK sont des substrats de transporteurs cellulaires potentiellement impliqués dans la résistance au traitement. Nous avons donc entrepris de doser ces ITK à l’intérieur même des cellules, d’abord in vitro afin d’évaluer ces mécanismes de transport, puis in vivo dans les cellules de patients traités par ces ITK. Un lien a ainsi été montré entre la capacité d’incorporation des molécules et la réponse au traitement. Enfin, le versant pharmacogénétique de l’un de ces transporteurs (MDR1) a été étudié, indiquant une relation entre certains haplotypes ou polymorphismes et la concentration plasmatique d’une part et la réponse à l’imatinib d’autre part. En conclusion, ces différentes stratégies basées sur le dosage plasmatique ou intracellulaire et sur la pharmacogénétique semblent apporter des éléments permettant l’amélioration de la réponse au ITK ou la détection précoce de mauvaise réponse. / During the last decade, tyrosine kinases inhibitors (TKI) have dramatically changed the prognosis of several cancers such as chronic myeloid leukaemia (CML) or gastro-intestinal stromal tumours (GIST). They are widely used in the treatment of various malignant pathologies, leading to a prolonged overall survival. However, some patients do not show improvement when treated with TKI. The supposed mechanisms are multifactorial and could have an origin in pharmacokinetics, pharmacodynamics or pharmacogenomics. Indeed, one of the major reasons of common variability of these TKI involves their metabolism by cytochrome 3A4, whose expression is subjected to many factors. The aim of this thesis was to deepen these mechanisms and to assess some strategies to increase the efficacy of these drugs. This work consisted first in developing a rapid and sensitive chromatographic method allowing determination of nine commercialised (or in advanced clinical development) TKI. Serving as a basis for therapeutic drug monitoring, this was used as part of CML management to measure imatinib plasmatic concentration of more than 3000 patients. The clinical information of these patients was recorded in a database and used as support for the evaluation of the response according to concentration. Thus, we confirmed that patients having concentration higher than the effectiveness threshold of 1000 ng/mL got higher probability of response. In the same way, we assessed relationship between imatinib concentration and efficacy in GIST and found an effectiveness threshold closed to 800 ng/mL. However, several factors of variability remain unmanageable with only plasmatic determination. Indeed, literature reported that some TKI were substrates of cellular transporters, potentially involved in the resistance to treatment. We therefore decided to determine concentration of these TKI into the cells, first in vitro to assess these mechanisms of transport, and then in vivo into the cells of patients treated by these TKI. A link was shown between the incorporation ability of molecules and the response to the treatment. Finally, a pharmacogenetic approach showed a relationship between some haplotypes or polymorphisms of a transporter (MDR1) and plasmatic concentration on one hand, and response to the imatinib on the other hand. In conclusion, these different strategies based on plasmatic or intracellular determination of TKI and on pharmacogenomics contribute to improvement of the response to TKI or early detection of non-response.

Introdução: Em pacientes críticos, como os grandes queimados, todos os parâmetros farmacocinéticos (absorção, distribuição, metabolismo e excreção) de muitas classes de drogas, incluindo antimicrobianos, estão alterados. Devido à forte associação entre a terapia antimicrobiana adequada em pacientes com queimaduras e mortalidade, intervenções como o monitoramento terapêutico de drogas podem ser uteis para otimizar a concentração sérica desses agentes em diferentes estágios do estado hiperdinâmico. Portanto, é possível melhorar desfecho clínico e sobrevivência além de reduzir o desenvolvimento de resistência. O objetivo deste estudo foi analisar o impacto em mortalidade de uma estratégia de ajuste de dose de acordo com o monitoramento terapêutico e modelagem farmacocinética/farmacodinâmica em pacientes de uma Unidade de Terapia Intensiva (UTI) para Queimados. Métodos: Um estudo comparativo, retrospectivo, foi conduzido entre pacientes admitidos com pneumonia, infecção em queimadura, infecção de corrente sanguínea e/ou infecção do trato urinário associados à assistência à saúde em uma UTI para Queimados do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Estes pacientes foram divididos em dois grupos: aqueles admitidos de maio de 2005 a outubro de 2008 que receberam antibioticoterapia em regime de dose convencional proposto pelo Grupo de Controle de Infecção Hospitalar do HC-FMUSP e aqueles admitidos de novembro de 2008 a junho de 2011 que receberam terapia antimicrobiana com dose ajustada de acordo com o monitoramento plasmático e modelagem farmacocinética. Características gerais dos dois grupos foram analisadas e desfechos clínicos (melhora dos sinais e sintomas da infecção), mortalidade em 14 dias e mortalidade hospitalar foram comparados. Resultados: 63 pacientes admitidos na UTI de Queimados apresentaram os critérios de inclusão para o grupo de tratamento convencional e 77 para o grupo de tratamento monitorado. Comparando dois grupos homogêneos em suas características gerais, houve diferenças quanto ao número de desbridamentos realizados e história de alcoolismo e uso de drogas ilícitas, mais frequentes no grupo de tratamento monitorado. Melhora clínica ocorreu em 56% dos pacientes sob regime monitorado e a mortalidade hospitalar foi similar entre os grupos. Pertencer a um dos grupos de tratamento não afetou o prognóstico. Na análise multivariada final, variáveis significativamente associadas com mortalidade hospitalar foram superfície corporal queimada maior que 30%, idade mais avançada e sexo masculino. Conclusão: Nosso estudo demonstrou que a estratégia de monitoramento terapêutico de antimicrobianos não alterou prognóstico de pacientes queimados. Acreditamos que são necessários mais estudos para embasar esta estratégia / Introduction: In critical patients, such as burn patients, pharmacokinetic parameters (absorption, distribution, metabolism and excretion) of many classes of drugs, including antibiotics, are altered. The aim of this study was to compare two groups of burned patients under treatment for healthcare associated infections with and without therapeutic drug monitoring (TDM) based on PK/PD modeling. Methods: A comparative study was conducted with patients with healthcare-associated pneumonia, burn infection, bloodstream infection and urinary tract infection in the Burn Intensive Care Unit (ICU) of a tertiary-care hospital. These patients were divided into two groups: 1) those admitted from May 2005 to October 2008 who received conventional antimicrobial dose regimen; and 2) those admitted from November 2008 to June, 2011 who received antibiotics with doses adjusted according to plasma monitoring and pharmacokinetics modeling. General characteristics of the groups were analyzed and clinical outcomes, 14-day and in-hospital mortality. Results: 63 patients formed the conventional treatment group and 77 the monitored treatment group. The groups were very homogeneous. Improvement occurred in 56% of the patients under monitored treatment and the in-hospital mortality was similar between groups. In the final multivariate models, variables significantly associated with in-hospital mortality were total burn surface area (TBSA) > 30%, older age and male sex. Treatment group did not affect the prognosis. Conclusions: TDM for antimicrobial treatment did not alter the prognosis of burn patients. More trials are needed to support the use of TDM to optimize treatment in burn patients

Within the field of depression the “monoamine hypothesis” has been the leading theory to explain the biological basis of depression. This theory proposes that the biological basis of depression is due to a deficiency in one or more of three key neurotransmitter systems, namely noradrenaline, dopamine and serotonin which are thought to mediate the therapeutic actions of virtually every known antidepressant agent. Citalopram is a selective serotonin-reuptake inhibitor (SSRI) used for the treatment of depression and anxiety disorders. Citalopram is a racemic compound, in other words composed of a 50:50 mixture of two enantiomers (S-(+)-citalopram and R-(-)-citalopram) and with one of the enantiomers (S-(+)-citalopram) accounting for the inhibitory effect. At the time of introduction of citalopram the physician needed a therapeutic drug monitoring service to identify patients with interactions, compliance problems and for handling questions concerning polymorphic enzymes and drug metabolism. An achiral analytical separation method based on solid-phase extraction followed by high-performance liquid chromatography (HPLC) was developed for routine therapeutic drug monitoring (TDM) of citalopram and its two main demethylated metabolites. As the data available on citalopram were from achiral concentration determinations and to be able to further investigate citalopram enantiomers effects and distribution, a chiral method for separation of the enantiomers of citalopram and its demethylated metabolites was established. The advances within chiral separation techniques have made measurement of the concentrations of the individual enantiomers in biological fluids possible. The process behind enantioselective separation is however not fully understood and the mechanism behind the separation can be further scrutinized by the use of multivariate methods. A study of the optimization and characterization of the separation of the enantiomers of citalopram, desmethylcitalopram and didesmethylcitalopram on an acetylated ß-cyclodextrin column, by use of two different chemometric programs - response surface modelling and sequential optimization was performed. Sequential optimization can be a quicker mean of optimizing a chromatographic separation; response surface modelling, in addition to enabling optimization of the chromatographic process, also serves as a tool for learning more about the separation mechanism. Studies of the antidepressant effect and pharmacokinetics of citalopram have been performed in adults, but the effects on children and adolescents have only been studied to a minor extent, despite the increasing use of citalopram in these age groups. A study was initiated to investigate adolescents treated for depression, with respect to the steady-state plasma concentrations of the enantiomers of citalopram and its demethylated metabolites. The ratios between the S- and R-enantiomers of citalopram and didesmethylcitalopram were in agreement with studies involving older patients. The concentrations of the S-(+)- and R-(-) enantiomers of citalopram and desmethylcitalopram were also in agreement with values from earlier studies. The results indicate that the use of oral contraceptives may have some influence on the metabolism of citalopram. This might be because of an interaction of the contraceptive hormones with the polymorphic CYP2C19 enzyme. Even though the SSRIs are considered less toxic compared with older monoamine-active drugs like the tricyclic/tetracyclic antidepressants, the risk of developing serious side effects such as ECG abnormalities and convulsions has been seen for citalopram, when larger doses have been ingested. Furthermore, fatal overdoses have been reported where citalopram alone was the cause of death. Data on the toxicity of each of the enantiomers in humans have not been reported and no data on blood levels of the enantiomers in cases of intoxication have been presented. An investigation was initiated on forensic autopsy cases where citalopram had been found at the routine screening and these cases were further analysed with enantioselective analysis to determine the blood concentrations of the enantiomers of citalopram and metabolites. Furthermore the genotyping regarding the polymorphic enzymes CYP2D6 and CYP2C19 were performed. In 53 autopsy cases, we found increasing S/R ratios with increasing concentrations of citalopram. We found also that high citalopram S/R ratio were associated with high parent drug to metabolite ratio and may be an indicator of recent intake. Only 3.8 % were found to be poor metabolizers regarding CYP2D6 and for CYP2C19 no poor metabolizer was found. Enantioselective analysis of citalopram and its metabolites can provide valuable information about the time that has elapsed between intake and death. Genotyping can be of help in specific cases but the possibility of pharmacokinetic interactions is apparently a far greater problem than genetic enzyme deficiency. / On the day of the public defence the status of article IV was: Submitted.

Introdução: Em pacientes críticos, como os grandes queimados, todos os parâmetros farmacocinéticos (absorção, distribuição, metabolismo e excreção) de muitas classes de drogas, incluindo antimicrobianos, estão alterados. Devido à forte associação entre a terapia antimicrobiana adequada em pacientes com queimaduras e mortalidade, intervenções como o monitoramento terapêutico de drogas podem ser uteis para otimizar a concentração sérica desses agentes em diferentes estágios do estado hiperdinâmico. Portanto, é possível melhorar desfecho clínico e sobrevivência além de reduzir o desenvolvimento de resistência. O objetivo deste estudo foi analisar o impacto em mortalidade de uma estratégia de ajuste de dose de acordo com o monitoramento terapêutico e modelagem farmacocinética/farmacodinâmica em pacientes de uma Unidade de Terapia Intensiva (UTI) para Queimados. Métodos: Um estudo comparativo, retrospectivo, foi conduzido entre pacientes admitidos com pneumonia, infecção em queimadura, infecção de corrente sanguínea e/ou infecção do trato urinário associados à assistência à saúde em uma UTI para Queimados do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Estes pacientes foram divididos em dois grupos: aqueles admitidos de maio de 2005 a outubro de 2008 que receberam antibioticoterapia em regime de dose convencional proposto pelo Grupo de Controle de Infecção Hospitalar do HC-FMUSP e aqueles admitidos de novembro de 2008 a junho de 2011 que receberam terapia antimicrobiana com dose ajustada de acordo com o monitoramento plasmático e modelagem farmacocinética. Características gerais dos dois grupos foram analisadas e desfechos clínicos (melhora dos sinais e sintomas da infecção), mortalidade em 14 dias e mortalidade hospitalar foram comparados. Resultados: 63 pacientes admitidos na UTI de Queimados apresentaram os critérios de inclusão para o grupo de tratamento convencional e 77 para o grupo de tratamento monitorado. Comparando dois grupos homogêneos em suas características gerais, houve diferenças quanto ao número de desbridamentos realizados e história de alcoolismo e uso de drogas ilícitas, mais frequentes no grupo de tratamento monitorado. Melhora clínica ocorreu em 56% dos pacientes sob regime monitorado e a mortalidade hospitalar foi similar entre os grupos. Pertencer a um dos grupos de tratamento não afetou o prognóstico. Na análise multivariada final, variáveis significativamente associadas com mortalidade hospitalar foram superfície corporal queimada maior que 30%, idade mais avançada e sexo masculino. Conclusão: Nosso estudo demonstrou que a estratégia de monitoramento terapêutico de antimicrobianos não alterou prognóstico de pacientes queimados. Acreditamos que são necessários mais estudos para embasar esta estratégia / Introduction: In critical patients, such as burn patients, pharmacokinetic parameters (absorption, distribution, metabolism and excretion) of many classes of drugs, including antibiotics, are altered. The aim of this study was to compare two groups of burned patients under treatment for healthcare associated infections with and without therapeutic drug monitoring (TDM) based on PK/PD modeling. Methods: A comparative study was conducted with patients with healthcare-associated pneumonia, burn infection, bloodstream infection and urinary tract infection in the Burn Intensive Care Unit (ICU) of a tertiary-care hospital. These patients were divided into two groups: 1) those admitted from May 2005 to October 2008 who received conventional antimicrobial dose regimen; and 2) those admitted from November 2008 to June, 2011 who received antibiotics with doses adjusted according to plasma monitoring and pharmacokinetics modeling. General characteristics of the groups were analyzed and clinical outcomes, 14-day and in-hospital mortality. Results: 63 patients formed the conventional treatment group and 77 the monitored treatment group. The groups were very homogeneous. Improvement occurred in 56% of the patients under monitored treatment and the in-hospital mortality was similar between groups. In the final multivariate models, variables significantly associated with in-hospital mortality were total burn surface area (TBSA) > 30%, older age and male sex. Treatment group did not affect the prognosis. Conclusions: TDM for antimicrobial treatment did not alter the prognosis of burn patients. More trials are needed to support the use of TDM to optimize treatment in burn patients

Magister Scientiae - MSc / Indinavir is a potent and well tolerated protease inhibitor drug used as a component of the highly active antiretroviral therapy (HAART) of HIV/AIDS, which results in pharmacokinetics that may be favourable or adverse. These drugs work by maintaining a plasma concentration that is sufficient to inhibit viral replication and thereby suppressing a patient’s viral load. A number of antiretroviral drugs, including indinavir, undergo metabolism that is catalysed by cytochrome P450-3A4 enzyme found in the human liver microsomes. The rate of drug metabolism influences a patient’s response to treatment as well as drug interactions that may lead to life-threatening toxic conditions, such as haemolytic anaemia, kidney failure and liver problems. Therapeutic drug monitoring (TDM) during HIV/AIDS treatment has been suggested to have a potential to reduce drug toxicity and optimise individual therapy. A fast and reliable detection technique, such as biosensing, is therefore necessary for the determination of a patient’s metabolic profile for indinavir and for appropriate dosing of the drugs. In this study biosensors developed for the determination of ARV drugs comprised of cysteamine self-assembled on a gold electrode, on which was attached 3-mercaptopropionic acid-capped palladium telluride (3-MPA-PdTe) or thioglycolic acid-capped palladium telluride (TGA-PdTe) quantum dots that are cross-linked to cytochrome P450-3A4 (CYP3A4) in the presence of 1-ethyl-3(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide. The quantum dots were synthesized in the presence of capping agents (3-MPA or TGA) to improve their stability, solubility and biocompatibility. The capping of PdTe quantum dots with TGA or 3-MPA was confirmed by FTIR, where the SH group absorption band disappeared from the spectra of 3-MPA-PdTe and TGA-PdTe. The particle size of the quantum dots (< 5 nm) was estimated from high resolution transmission electron microscopy (HRTEM) measurements. Optical properties of the materials were confirmed by UV-Vis spectrophotometry which produced absorption iii bands at ~320 nm that corresponded to energy band gap values of 3 eV (3.87 eV) for TGAPdTe (3-MPA-PdTe) quantum dots. The electrocatalytic properties of the quantum dots biosensor systems were studied by cyclic voltammetry (CV) for which the characteristic reduction peak at 0.75 V was used to detect the response of the biosensor to indinavir. Results for indinavir biosensor constructed with 3-MPA-SnSe quantum dots are also reported in this thesis. The three biosensors systems were very sensitive towards indinavir; and gave low limits of detection (LOD) values of 3.22, 4.3 and 6.2 ng/mL for 3-MPA-SnSe, 3-MPA-PdTe and TGA-PdTe quantum dots biosensors, respectively. The LOD values are within the ‘maximum plasma concentration’ (Cmax) value of indinavir (5 - 15 ng/mL) normally observed 8 h after drug intake.