Background: Sweden is among the top countries with the greatest use of e-prescriptions at a national level. A clinical decision support system called Electronic Expert Support (EES) is available at all pharmacies in Sweden to examine e-prescriptions in connection with the dispensing to prevent drug related problems (DRPs). DRPs result in patient suffering and substantial costs for society. The types of alerts generated for pediatric patients at Swedish pharmacies using EES-system has not been studied before, to the best of our knowledge. Aim: The aim of this research is to study the use of EES at pharmacies in Sweden for the pediatric population (ages 0-12 years), by describing what types of alerts for potential DRPs are generated, how they are handled and how the use of EES has changed over time. Method: Data on the number and categories of EES analyses, alerts, and resolved alerts was provided by the Swedish eHealth Agency. Results: The study shows that the use of EES has increased. The most common type of generated alert for a potential DRP among pediatric was high dose pediatric (30,3% of all alerts generated). The most common type of alert for a potential DRP that was resolved among pediatrics was therapy duplication (45,8%). The most common reason for closing an alert was dialogue with patient for verification of the treatment (66,3% of all closed alerts). Conclusion: Knowledge of which type of alerts that are the most common may contribute to increased prescriber awareness of important potential DRPs. Future studies should investigate the clinical relevance of the generated alerts for the pediatric population.

The clinical support system Electronic Expert Support (EES) is available at all pharmacies in Sweden to examine electronic prescriptions when dispensing to prevent drug-related problems (DRPs). DRPs are common, and result in patient suffering and substantial costs for society. The aim of this research was to study the use of EES for the pediatric population (ages 0-12 years), by describing what types of alerts are generated for potential DRPs, how they are handled, and how the use of EES has changed over time. Data on the number and categories of EES analyses, alerts, and resolved alerts were provided by the Swedish eHealth Agency. The study shows that the use of EES has increased. The most common type of alert for a potential DRP among pediatric patients was regarding high doses in children (30.3% of all alerts generated). The most common type of alert for a potential DRP that was resolved among pediatrics was therapy duplication (4.6% of the alerts were resolved). The most common reason for closing an alert was dialogue with patient for verification of the treatment (66.3% of all closed alerts). Knowledge of which type of alerts are the most common may contribute to increased prescriber awareness of important potential DRPs.

Background: Covid-19 is a serious infectious disease that was first discovered in China in 2019. The disease spread very quickly, infecting over 40 million globally and leading to more than a million deaths. The damage caused by the corona infection led to severe thromboembolic conditions that led to death. Therefore, anticoagulants were used in connection with corona to prevent the thromboembolic conditions. But has the use of anticoagulants in covid-19 patients really affected mortality?    Aim: To make a systematic review that explores whether anticoagulant use among COVID-19 patients affect mortality.    Methods: A systematic search was conducted September in 2022 of published studies on PubMed associated with mortality and use of anticoagulants in covid-19 patients. The articles reviewed were selected based on defined PICO and inclusion and exclusion criteria. Types of studies reviewed were cohort and case-control studies.    Results & conclusions:   A total of 20 different studies were studied and based on them it is concluded that anticoagulant treatment associated with lower mortality in severely ill covid-19 patients has been demonstrated. However, bleeding risk was observed in other covid-19 patients due to use of anticoagulants.

Background: Defined daily dose (DDD) is a unit that gives an estimate of drug utilization. The DDDs that are developed today are only based on adult’s drug use. That means that the DDDs for adults may not necessarily apply to children. 

Aim: To calculate recommended daily dose for boys and girls in different ages and compare it with DDD for adults for paracetamol, phenoxymethylpenicillin, desloratadine and melatonin.  

Methods: This descriptive cross-sectional study was conducted September-October 2021. Boys and girls in ages 1, 5, 12 and 16 years were included. Data was retrieved from FASS.se, tillväxtkurvor.se and WHO Collaborating Centre for Drug Statistics Methodology. 

Results: The children’s daily doses are lower than DDD for adults for paracetamol for all ages, phenoxymethylpenicillin for ages 1, 5 and 12 and desloratadine for ages 1 and 5. The daily doses of phenoxymethylpenicillin aged 16 are higher than DDD for adults. Daily doses for melatonin and desloratadine age 12 and 16 were the same as DDD for adults. Paracetamol and phenoxymethylpenicillin have variations in the daily doses for the children. Girls in all ages except from 12 years and the youngest children had lowers doses. Desloratadine ages 1 and 5 had the same dose and ages 12 and 16 had the same dose. For melatonin the children received the same doses. 

Conclusion: The calculated recommended daily doses for children are to some extent in line with WHO DDDs. In order to use WHO DDDs in children, it is important to have knowledge of which drugs and ages they can be applied for.  

Clofazimine is classified as a WHO group B drug for the treatment of rifampin-resistant tuberculosis. QT prolongation, which is associated with fatal cardiac arrhythmias, is caused by several antitubercular drugs, including clofazimine, but there are no data quantifying the effect of clofazimine concentration on QT prolongation. Our objective was to describe the effect of clofazimine exposure on QT prolongation. Fifteen adults drug-susceptible tuberculosis patients received clofazimine monotherapy as 300mg daily for 3 days, followed by 100mg daily in one arm of a 2-week, multiarm early bactericidal activity trial in South Africa. Pretreatment Fridericia-corrected QT (QTcF) (105 patients, 524 electrocardiograms [ECGs]) and QTcFs from the clofazimine monotherapy arm matched with clofazimine plasma concentrations (199 ECGs) were interpreted with a nonlinear mixed-effects model. Clofazimine was associated with significant QT prolongation described by a maximum effect (Emax) function. We predicted clofazimine exposures using 100-mg daily doses and 2 weeks of loading with 200 and 300mg daily, respectively. The expected proportions of patients with QTcF change from baseline above 30 ms (DQTcF. 30) were 2.52%, 11.6%, and 23.0% for 100-, 200-, and 300-mg daily doses, respectively. At steady state, the expected proportion with Delta QTcF of >30 ms was 23.7% and with absolute QTcF of >450 ms was 3.42% for all simulated regimens. The use of loading doses of 200 and 300mg is not predicted to expose patients to an increased risk of QT prolongation, compared with the current standard treatment, and is, therefore, an alternative option for more quickly achieving therapeutic concentrations.

Biologics are an important part of modern healthcare and are mostly administered parenterally due to the fact that it is the route of administration that avoids degradation of biologics and ensures their systemic exposure. However, there is a need to develop oral drug delivery formulations for local treatment of diseases in the gastrointestinal tract (GI). Colloidal capsules is a formulation that can potentially facilitate oral administration of biologics. There have been studies on colloidal capsules and the various ways of manufacturing them, one of which is “Emulsion-based method”. The aim of this study was to produce colloidal capsules made of silica nanoparticles through emulsion-based method, coat them to study their pH-responsive release and characterize them. Encapsulation of a model protein in the silica colloidal capsules was also attempted. pH-responsive release was not studied due to limited access to the laboratory and, a literature study of articles about colloidal capsules was conducted instead, regarding different aspects of colloidal capsule synthesis and encapsulation of various compunds. Web of science was the database used to find scientific studies that specifically produced colloidal capsules. Colloidal capsules were synthesized using a Pickering-emulsion method. Commercially available SiO₂ nanoparticles were used to form the capsules by ultrasonication.  The hydrodynamic size and capsule morphology were analyzed using dynamic light scattering (DLS) and scanning electron microscopy (SEM), respectively. Zeta potential was measured through electrophoretic light scattering (ELS). Articles for the literature study were found using the “web of science” database. Colloidal capsules were successfully produced, coated and characterized. Additionally, the literature study shows that there diverse colloidal capsule synthesis conditions, model proteins and applications for colloidal capsules.

As of 26 May 2021, Regulation (EU) 2017/745 also known as the Medical Device Regulation (MDR) became applicable in the European Union, replacing the previous Directives for Medical Devices (93/42/EEC and 90/385/EEC). The new law significantly changed the European legal framework for medical devices, introducing new principles and responsibilities for the national authorities. As of the implementation of MDR, sponsors are required to submit notifications through the national Competent Authority in EU/EEA concerning clinical investigations of already CE-marked medical devices that are to be used within their intended purpose. The aim of this study was to investigate and assess the study documentations submitted with a notification of a clinical investigation concerning a medical device, and their alignment with what is required according to MDR and applicable national legislation and guidance. The method involved systematic verification of essential documents, including evidence of CE-marking and alignment with intended purposes. Systematic controls ensured consistency, and data analysis identified patterns and implications for regulatory adherence. The data analysis included all 42 notifications submitted to the Swedish Medical Products Agency within the timeframe 26/MAY/2021-31/MAY/2023. The results revealed a consistent submission of some essential documents, which demonstrated a foundational understanding of regulatory requirements, but also some notifications that lacked alignment with the MDR and applicable standards, suggesting a knowledge gap among sponsors and emphasising the need for enhanced awareness and compliance. 

Background: High blood pressure (BP) or hypertension is defined as a systolic and diastolic pressure over 140/90 mmHg. High blood pressure increases the risk for premature death, and previous research has shown that many patients do not reach targets and that there are differences between primary healthcare centers in the proportion of patient reaching targets. The reasons for these variations, however, are unknown. Aim: To investigate variations in blood pressure target achievement between primary care centers in Stockholm county and how different factors such as practice size, ownership, socioeconomic and antihypertensive drug treatment can influence this diversity. Method(s): This study was designed as a cross-sectional register study with a descriptive quantitative perspective. Data was collected from three sources: National Primary Care Quality register, Care Need Index for healthcare in Stockholm region and Stockholm County Council data warehouse VAL. The study included 179 out of all 227 primary care centers in the region. The proportion of all patients with hypertension reaching targets was assessed each year during 2019-2021, and correlations studied for potential predictors. Results: there was a variation between primary care centers in target blood pressure fulfillment, ranging from 22-66% during 2021, 23-63% during 2020 and 33-66% during 2019, respectively. There was no overall difference between public and private centers in the proportion of patients reaching targets, but a larger practice variation among private centers. No correlation was found between the other studied factors and target blood pressure fulfillment during 2021. Conclusion: There was a variation between primary care centers in the proportion of patients reaching blood pressure targets. Different practices may change ranking between years and other factors than practice size, ownership and socioeconomic appears to explain the variation.

The number of poorly water-soluble drugs acquiring a high lipophilicity (BCS class II) have increased tremendously in the pharmaceutical development pipeline over the past decades. One of the solutions that has been conducted to overcome the low aqueous solubility problem was to co-administer these drugs with lipids or fats as lipid-based formulations (LBF). In vitro lipid digestion assays for drug loaded LBF have been used to predict the behaviour of these drugs in vivo in the GI tract. The aim of this study was to examine the feasibility of using Ultra-Thin Large Area PDMS membrane of (~10 μm) thickness with Rotating Membrane Diffusion Cell (RMDC) for in vitro lipolysis-permeation experiments for Felodipine loaded Lipid-based Formulation. Membrane fabrication was done using Sylgard 184 elastomer kit and spin-coater device to get the ultra-thin membranes of approximately 10 μm thickness. Felodipine loaded LBF (22mg/g Felodipine, LBF type: MC-IIIA) was digested in the RMDC at 100 rpm speed for 60 min at 37°C. 75 μl of Lucifer Yellow (10 mM) was used as a membrane integrity marker and was added to the donor chamber of (225 mL) volume prior to digestion to check for mass transfer through the membrane in the receiver chamber (70 mL). During the digestion phase, the maximum ionised fatty acids was 0.402 mmol at 59.6 min, however, the unionised fatty acids during back titration have reached 0.86 at 61.4 min. Lucifer Yellow mass transfer graphs showed a steady increase in the area under the curve at the time point 20 min, where it reached approximately 75 nmol min cm-2. The experiment needs to be repeated to be able to identify a more rigorously justified leak criterion for LY-PDMS. It should be noted that PDMS-LY partition experiments were planned, so that the partitioning affinity could be determined to predict the flux of Lucifer Yellow through PDMS. This secondary method would provide a priority leak criterion.

Background: Antidepressant medications are widely prescribed in Sweden, yet comprehensivelongitudinal studies examining trends in their utilization over time are scarce. This thesisaddresses this gap by exploring the patterns of antidepressant drug utilization in Sweden from1977 to 2023.

Aims: The primary aim of this study is to investigate the longitudinal trends in antidepressantutilization across different demographic groups, including age and gender, and various categoriesof antidepressants.

Methods: A quantitative-descriptive repeated cross-sectional design is employed, utilizingaggregated sales data from 1977 to 2000 and prescription data from 2006 to 2023. Defined DailyDose per 1000 inhabitants per day (DDD/TID) and Patients per 1000 inhabitants are used asprincipal analytical metrics. The study population comprises all men and women of all ages whoobtained at least one prescription for antidepressants during the study period.

Results: The analysis reveals a notable escalation in antidepressant consumption over the studyperiod. Sales statistics indicate a significant increase in antidepressant usage from approximately6 DDD/TID in 1977 to 48 DDD/TID by 2000. Prevalence data from 2006 to 2023 shows a rise inpatients per 1000 inhabitants, reaching 114 in 2023, with women receiving more prescriptionsthan men nearly doubling that of men by 2023. Selective Serotonin Reuptake Inhibitors(SSRIs)(N06AB) experienced a significant increase between 1992 and 2000, while TricyclicAntidepressants (TCAs) declined gradually. Other antidepressants (N06AX) also showed a slowincrease, competing with SSRIs by 2023. Antidepressant usage was higher among adults,particularly those over 60, compared to younger individuals.

Conclusion: This thesis underscores the evolving landscape of antidepressant drug utilization inSweden, highlighting the need for tailored interventions to address demographic-specific patternsand optimize mental health care delivery. 

OrBiTo was a precompetitive collaboration focused on the development of the next generation of Oral Biopharmaceutics Tools. The consortium included world leading scientists from nine universities, one regulatory agency, one non-profit research organisation, three small/medium sized specialist technology companies together with thirteen pharmaceutical companies. The goal of the OrBiTo project was to deliver a framework for rational application of predictive biopharmaceutics tools for oral drug delivery. This goal was achieved through novel prospective investigations to define new methodologies or refinement of existing tools. Extensive validation has been performed of novel and existing biopharmaceutics tools using historical datasets supplied by industry partners as well as laboratory ring studies. A combination of high quality in vitro and in vivo characterizations of active drugs and formulations have been integrated into physiologically based in silico biopharmaceutics models capturing the full complexity of gastrointestinal drug absorption and some of the best practices has been highlighted. This approach has given an unparalleled opportunity to deliver transformational change in European industrial research and development towards model based pharmaceutical product development in accordance with the vision of model-informed drug development.

Objective: GH deficiency (GHD) in adults is characterized by elevated body mass index (BMI), increased waist girth (WG) and increased fat mass (FM). Information about how these indicators of obesity affect the lipid profile and quality of life (QoL) of GHD subjects is scarce. It is also unclear how changes in these indicators brought about by GH replacement influence lipids and QoL. Design and methods: Adult GHD Subjects from the Pfizer International Metabolic Database were grouped according to BMI (n = 291 with BMI < 25 kg/m(2), n = 372 with BMI 25-30 kg/m(2), n = 279 with BMI > 30 kg/m(2)), WG (n = 508 with normal WG, n = 434 with increased WG) and FM (n = 357) and according to changes in these variables after 1 year of GH replacement. Serum IGF-1 concentrations, lipid concentrations and QoL using the QoL Assessment of GHD in Adults questionnaire were assessed at baseline and after 1 year of treatment. Results: At baseline, total and low-density lipoprotein (LDL) cholesterol were similarly elevated in the BMI and WG groups, but high-density lipoprotein (HDL) cholesterol decreased and triglycerides increased with increasing BMI and WG. QoL was progressively poorer with increasing BMI and WG. After 1 year of GH replacement, total and LDL cholesterol and QoL improved in all BMI, WG and FM groups. Conclusions: Variables of obesity adversely affect the already unfavourable lipid profile in GHD Subjects by decreasing HDL cholesterol, but do not counteract the positive effect of GH replacement on LDL cholesterol. Similarly, QoL is influenced by obesity, but responds equally well to GH treatment independent of BMI, WG and FM.

Objective: The aim of the present study was to clarify the relationship between GH deficiency (GHD) andsome cardiovascular risk factors and to analyse the effect of GH replacement therapy in a large numberof patients over a prolonged period of time.Design: Data for analysis were retrieved from KIMS (Pfizer International Metabolic Database). Serumconcentrations of total cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein(LDL)-cholesterol and triglycerides were obtained from 2589 patients at baseline and from 1206patients after 1 and 2 years of GH replacement therapy. Body mass index (BMI), waist and hip, restingblood pressure and body composition were also measured.Results: At baseline, the unfavourable effects of GHD were most obvious in the lipid profiledemonstrating elevated mean total and LDL-cholesterol, in the increased waist circumference and theelevated BMI. The cholesterol concentration, BMI and body composition were significantly adverselyaffected by a number of factors, including age, sex and the use of anti-epileptic drugs. The therapeuticeffect of GH was essentially uniform across the whole population. GH replacement reduced significantlythe mean total and LDL-cholesterol, the waist circumference and the fat mass and was maintainedduring 2 years.Conclusions: This analysis of a large number of patients confirmed that GHD adults present with anincreased cardiovascular risk. The sustained improvement of the adverse lipid profile and bodycomposition suggests that GH replacement therapy may reduce the risk of cardiovascular disease andthe premature mortality seen in hypopituitary patients with untreated GHD.

Multiple-unit tablets formed from mixtures of microcrystalline cellulose pellets and disintegrants (Ac-Di-Sol, Primojel or Kollidon CL) by compaction were investigated with the aim of controlling tablet tensile strength and disintegration time. The effects of pellet porosity, compaction pressure, and type and amount of disintegrant were studied. Primojel made the pellets less prone to deformation during compression, while the other two disintegrants had very minor effects on the compression behavior. Ac-Di-Sol and Primojel generally increased the tablet tensile strength, whereas the effect of Kollidon CL was dependent on the initial pellet porosity. Kollidon CL was found to significantly reduce the disintegration time, but the other two disintegrants had variable efficacy, and for the low-porosity pellets significantly increased the disintegration time. These results are interpreted as resulting from the interplay between the mechanical characteristics of the pellets and the mechanisms of action of the disintegrants.

Abstract

Background: Out of approximately 1,6 million children in Sweden, about 350 are diagnosed with cancer each year. Chemotherapeutic agents are commonly used in the treatment of various cancer types in pediatric oncology. While it is established that certain chemotherapeutic agents induce hepatotoxicity as a side effect, a comprehensive assessment of the prevalence of hepatotoxicity in pediatric oncology populations has been lacking.

Aim: This study aims to investigate the prevalence of hepatotoxicity in pediatric patients between 0-18 years with intracranial and extracranial solid tumors. 

Method: A retrospective cohort study was conducted, at Uppsala University Children’s Hospital. Data regarding administered chemotherapeutic treatment and liver values such as alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT), alkaline phosphatase (ALP), bilirubin and lactate dehydrogenase (LD), were collected over a 4-month period from start of treatment. Tto identify the treatment cycle in which hepatotoxicity occurred the data were divided into treatment cycles. During each treatment cycle, the liver values were collected on day 1, 8, 15, 22 or adjacent days. For patients experiencing hepatotoxicity, it was graded according to Common Terminology Criteria for Adverse Events (CTCAE) version 5. 

Results: Fifty patients were included, and the study yielded four main findings: 1) Approximately 30% of pediatric oncology patients experienced hepatotoxicity, 2) Treatment adjustments were implemented, such as dose reduction and treatment pause, for those with grade 3 and 4 toxicity, 3) Hepatotoxicity tends to exhibit a higher prevalence in males, 4) Hepatotoxicity tends to exhibit a higher prevalence in younger children. 

Conclusion: The observed prevalence of hepatotoxicity exceeded initial expectations, with approximately 30% suffer from hepatotoxicity due to chemotherapeutic treatment. However, future studies with larger sample size are needed. 

Factors considered important for the interparticulate bonding structure and mechanical strength of pharmaceutical compacts were studied in this thesis.

Fractures appear to propagate mainly around rather than through grains during strength testing. Large deviations from theoretical strength values in addition to an effect of particle size were thus obtained when compaction was performed to zero porosity or obtained by extrapolation to zero porosity. When high compaction loads were used, the excess energy was to a large extent used for elastic recovery and/or alteration of the solid-state structure.

Filtering out of weak distance forces (intermolecular forces) by compaction in a liquid with a sufficiently high dielectric constant appears to provide reliable information on interparticulate bonding mechanisms. The best correlation between physiochemical properties of the liquids and the gradual decrease in tensile strength of the compacts was achieved using the dielectric constant. The weak distance forces appeared to be screened out when the liquid compaction medium had a dielectric constant of 18. The remaining tensile strength was then believed to be the result of interparticulate bonding by solid bridges for most materials. However, for most pharmaceutical materials, weak distance forces seem to dominate. Of all the materials tested, solid bridges seemed to be the most important bonding mechanism for sodium and potassium chloride. Increasing the particle size and compaction pressure of materials with the capacity to form solid bridges seemed to facilitate the bond formation process. Addition of a dry binder or milling the particles counteracted the formation of solid bridges, probably by reducing the concentration of stress at certain points in the compact, a prerequisite for the establishment of solid bridges.

Both the tablet surface area and the interparticulate distance may affect the proportion of external surface area participating in interparticulate bonding. For materials prone to develop solid bridges, the actual surface area involved in bond formation is more important than the space between the particles, i.e. compensation of the tensile strength of a tablet for the surface area and the mean interparticulate distance will probably not reflect the nature of the dominating bond type. However, for the other materials, ranking of the materials according to tensile strength adjusted for surface area and mean interparticulate distance gave a reflection of dominating interparticulate bonding type.

Aim: Therapeutic drug monitoring of tacrolimus based on whole blood drug concentrations is routinely performed. The concentration of tacrolimus in peripheral blood mononuclear cells (PMBCs) is likely to better reflect drug exposure at the treatment target site. We aimed to describe the relationship between tacrolimus whole blood and PBMC concentrations, and the influence of patient characteristics on this relationship by developing a population pharmacokinetic model.

Methods: We prospectively enrolled 63 stable adult kidney-transplanted patients and collected dense (12-h, n = 18) or sparse (4-h, n = 45) pharmacokinetic profiles of tacrolimus. PBMCs were isolated from whole blood (Ficoll density gradient centrifugation), and drug concentrations in whole blood and PBMCs were analysed using liquid chromatography-mass spectrometry. Patient genotype (CYP3A4/5, ABCB1, NR1I2) was assessed with PCR. Population pharmacokinetic modelling and statistical evaluation was performed using NONMEM.

Results: Tacrolimus whole blood concentrations were well described using a two-compartment pharmacokinetic model with a lag-time and first-order absorption and elimination. Tacrolimus PBMC concentrations were best estimated from whole blood concentrations with the use of a scaling factor, the ratio of whole blood to PBMC concentrations (RC:PBMC), which was the extent of tacrolimus distribution into PBMC. CYP3A5*1 non-expressors and NR1I2-25 385T allele expressors demonstrated higher RC:PBMC ratios of 42.4% and 60.7%, respectively.

Conclusion: Tacrolimus PBMC concentration could not be accurately predicted from whole blood concentrations and covariates because of significant residual unexplained variability in the distribution of tacrolimus into PBMCs and may need to be measured directly if required for future studies.Keywords: immunosuppressants; pharmacogenetics; population pharmacokinetics; therapeutic drug monitoring; transplantation.

This study tackles the critical challenge of medication non-adherence in healthcare by pinpointing indicators related to medication adherence (IRMAs) across 39 European countries and Israel. Utilizing a structured expert survey methodology within the European Network to Advance Best Practices and Technology on Medication Adherence (ENABLE; COST Action CA19132), our research identified key country-specific IRMAs and collected data on these indicators to understand the multifaceted nature of medication adherence. The research was conducted in two phases: firstly, defining key IRMAs through a two-round expert survey, and secondly, gathering country-specific data on these IRMAs through literature reviews and additional expert surveys. The study revealed a diverse range of 26 top-ranked IRMAs, including six related to country characteristics, four to social/economic factors, three each to therapy-related and patient-related factors, one to condition-related factors, and nine to healthcare system-related factors. The availability of country-specific data on these IRMAs varied among the countries, highlighting the need for more comprehensive data collection and research. The findings from this study not only underscore the complexity of predicting medication adherence but also lay the groundwork for developing targeted, country-specific interventions to improve adherence. Moreover, this research offers valuable insights for policymakers, highlighting the importance of understanding the multifaceted nature of medication adherence and offering a valuable resource in formulating targeted health policies to enhance health outcomes and reduce the economic burden associated with medication non-adherence.

This study explores the genetic basis of the excitability trait and its correlation with hair whorl patterns in Swedish Standardbred trotters. Understanding these connections can provide insights into equine temperament, which is crucial for breeding and managing horses in sports and recreational activities. We investigated 49 trotters, collecting data on their hair whorls and conducting behaviour tests to assess their excitability. DNA was extracted from tail hair samples, and significant SNPs were identified through a genome-wide association study (GWAS) from a previous study on horse temperaments. The novel object test was used to measure excitability levels, ranking horses on a scale from 1 (very calm) to 7 (extremely excitable). The horses were categorized based on their hair whorl types: radial, clockwise, counterclockwise, and feather. Statistical analysis using Pearson’s Chi-Squared Test revealed no significant association between whorl types and excitability scores (p-value = 0.6932). Significant SNPs were identified on chromosomes 3, 8, 15, and 23, with the top 20 SNP locations selected for each chromosome based on FST values. These SNPs were annotated using the NCBI horse genome browser (equCab3). Notably, a SNP within the DIRAS2 gene, which has been implicated in attention deficit/hyperactivity disorder (ADHD) in humans, was highlighted. This SNP was further analysed using a TaqMan assay designed for this sequence.

Drug transport across cells and cell membranes in the human body is crucial for the pharmacological effect of drugs. Active transport governed by transport proteins plays an important role in this process. A vast number of transport proteins with a wide tissue distribution have been identified during the last 15 years. Several important examples of their role in drug disposition and drug-drug interactions have been described to date. Investigation of drug-drug interactions at the transport protein level are therefore of increasing interest to the academic, industrial and regulatory research communities.

The gene expression of transport proteins involved in drug transport was investigated in the jejunum, liver, kidney and colon to better understand their influence on the ADMET properties of drugs. In addition, the gene and protein expression of transport proteins in cell lines, widely used for predictions of drug transport and metabolism, was examined.

The substrate and inhibitor heterogeneity of many transport proteins makes it difficult to foresee whether the transport proteins will cause drug-drug interactions. Therefore, in vitro assays for OCT1 and OATP1B1, among the highest expressed transport proteins in human liver, were developed to allow investigation of the inhibitory patterns of these proteins. These assays were used to investigate two data sets, consisting of 191 and 135 registered drugs and drug-like molecules for the inhibition of OCT1 and OATP1B1, respectively. Numerous new inhibitors of the transport proteins were identified in the data sets and the properties governing inhibition were determined. Further, antidepressant drugs and statins displayed strong inhibition of OCT1 and OATP1B1, respectively. The inhibition data was used to develop predictive in silico models for each of the two transport proteins.

The highly polymorphic nature of some transport proteins has been shown to affect drug response and may lead to an increased risk of drug-drug interactions, and therefore, the OCT1 in vitro assay was used to study the effect of common genetic variants of OCT1 on drug inhibition and drug-drug interactions. The results indicated that OCT1 variants with reduced function were more susceptible to inhibition. Further, a drug-drug interaction of potential clinical significance in the genetic OCT1 variant M420del was proposed.

In summary, gene expression of transport proteins was investigated in human tissues and cell lines. In vitro assays for two of the highest expressed liver transport proteins were used to identify previously unknown SLC transport protein inhibitors and to develop predictive in silico models, which may detect previously known drug-drug interactions and enable new ones to be identified at the transport protein level. In addition, the effect of genetic variation on inhibition of the OCT1 was investigated.

Common genetic variants of the liver-specific human organic cation transporter 1 (OCT1; SLC22A1) have reduced transport capacity for substrates such as the antidiabetic drug metformin. The effect of the reduced OCT1 function on drug interactions associated with OCT1 has not been investigated and was, therefore, the focus of the study presented here. HEK293 cells expressing human OCT1-reference or the variants R61C, V408M, M420del and G465R were first used to study the kinetics and inhibition pattern of the OCT1 substrate 4-(4-(dimethylamino)styryl)-N-methylpyridinium (ASP(+)). In the second part OCT1-mediated (14)C-metformin uptake was studied in the presence of drugs administered concomitantly with metformin. Transport studies using ASP(+) showed that the function of the variants decreased in the following order: OCT1-reference = V408M = M420del >R61C > >G465R. Variants M420del and R61C were more sensitive to drug inhibition, with IC(50) values up to 23 times lower than those of the OCT1-reference. Uptake studies using (14)C-metformin were in qualitative agreement with those using ASP(+), with the exception that a larger reduction in transport capacity was observed for M420del. Concomitantly administered drugs, such as verapamil and amitriptyline, revealed potential drug-drug interactions at clinical plasma concentrations of metformin for OCT1-M420del.

The aim of this study was to investigate the gene and protein expression profiles of important drug transporting proteins in human cell lines commonly used for studies of drug transport mechanisms. Human cell lines used to transiently or stably express single transporters (HeLa, HEK293) and leukaemia cell lines used to study drug resistance by ABC-transporters (HL-60, K562) were investigated, and compared with organotypic cell lines (HepG2, Saos-2, Caco-2 and Caco-2 TC7). For gene expression studies, real-time PCR was used, while monospecific polyclonal antibodies were generated and used to investigate protein expression by immunohistochemistry. Thirty-six transporters were studied for gene expression and nine for protein expression. The antibodies were validated using expression patterns in human tissues. Finally, the function of one ubiquitously expressed transporter, MCT1; SLC16A1 was investigated using 14C-lactic acid as a substrate. In general, the adherent cell lines (HeLa, HEK293) displayed low transporter expression and the expression patterns were barely affected by transfection. The leukaemia cell lines (K562, HL-60) and Saos-2 also had low endogenous transporter expression, while the organotypic cell lines (HepG2 and Caco-2) showed higher expression of some transporters. Comparison of gene and protein expression profiles gave poor correlations, but better agreement was obtained for antibodies with a good validation score, indicating that antibody quality was a significant variable. Importantly, the monocarboxylic acid transporting protein MCT1 was significantly expressed in all, and functional in most of the cell lines, indicating that MCT1 may be a confounding factor when the transport of small anionic drugs is investigated.

The liver-specific organic cation transport protein (OCT1; SLC22A1) transports several cationic drugs including the antidiabetic drug metformin and the anticancer agents oxaliplatin and imatinib. In this study, we explored the chemical space of registered oral drugs with the aim of studying the inhibition pattern of OCT1 and of developing predictive computational models of OCT1 inhibition. In total, 191 structurally diverse compounds were examined in HEK293-OCT1 cells. The assay identified 47 novel inhibitors and confirmed 15 previously known inhibitors. The enrichment of OCT1 inhibitors was seen in several drug classes including antidepressants. High lipophilicity and a positive net charge were found to be the key physicochemical properties for OCT1 inhibition, whereas a high molecular dipole moment and many hydrogen bonds were negatively correlated to OCT1 inhibition. The data were used to generate OPLS-DA models for OCT1 inhibitors; the final model correctly predicted 82% of the inhibitors and 88% of the noninhibitors of the test set.

Introduktion: Läkemedel har en stor roll i vårt liv och användning av läkemedel påverkar vår miljö. De största utsläppen av läkemedel sker efter användningen och utsöndras i urinen. Slutligen hamnar de i avloppet och vattendrag och därefter når de oss och fiskar genom vattnet. Det finns få studier om hur läkemedelsanvändningen ser ut i relation till miljörisk.

Syfte: Syftet med denna tvärsnittsstudie var att undersöka data kring förbrukningen av NSAID och Paracetamol i relation till miljörisk.

Metod: Studien genomfördes genom datainsamling från Socialstyrelsens statistikdatabas för smärtstillande läkemedel och E-hälsomyndigheten statistikverktyg Concise för perioden 2010–2020. Förbrukningen av paracetamol (N02BE01) och NSAID (M01A) analyserades i kg som sålts på recept, receptfritt, till sjukhus och på öppenvård-rekvisition och bedömdes i förhållande till klassifikation av miljörisk.

Resultat: De mest använda läkemedlen var paracetamol, ibuprofen, naproxen och diklofenak. Paracetamol och ibuprofen har låg miljöfara och försumbar miljörisk. Naproxen har medium miljöfara och låg miljörisk. Miljöfara för diklofenak finns ej publicerat på regions Stockholms databas för läkemedelsmiljöpåverkan, men risken anses vara hög jämfört med andra NSAID. En stor andel av försäljningen av paracetamol, naproxen och diklofenak expedierades via recept. Förbrukningen av paracetamol, ibuprofen och naproxen har ökat medan konsumtionen av diklofenak har minskat med 71% under 2010–2020. Slutsats: Av de fyra mest använda smärtstillande läkemedel som inte är opioder, är naproxen och diklofenak skadliga för miljön eftersom de har högt respektive medium miljöfara. Det bästa alternativet är paracetamol och ibuprofen ur ett miljöperspektiv.

Background and objective: Holistic patient care is dependent upon the accurate and reliable flow of information between care settings and healthcare professionals (HCP). Inaccurate medical records may increase the risk of patient harm as HCPs risk continuing to prescribe a medication that has been discontinued or re-prescribing a medication that has previously been discontinued. The aim of this project was to analyse the HCPs documentation of medical changes in the patients’ medical records and evaluate the extent of adherence to a predefined criteria within the regions guidelines at six general practices (GP) across Jönköping County.

Study design: A retrospective observational study, reviewing 240 medical records between June-December 2019.

Main outcome measures: The number and the type of medication changes registered, and the extent to which the documentations adhered to regional guidelines concerning the criteria of the information that ought to be included in a documentation upon a registration of a medical change.

Results: There was an average of 63 (95% CI:53.4 – 73.2) medical changes identified across the six GPs. None of the documentations completely adhered to all points in the guideline. Follow-up plans was found to be the most omitted data point having only been mentioned in 2% of the medical changes. The name of the prescribed medication was mentioned on 378 occasions however, it was only accompanied with dosage form on 44% of occasions. In 9% of the medical records that were analysed it was not found to include any medical changes at all, instead it was either filled in with a “0” or the HCPs had for instance confirmed that the patients’ prescriptions had been renewed.

Conclusions: Despite the clear guidance regarding the content of documentation for a medical change, no documentation followed the guidelines fully. Adherence to the guidelines may be enhanced by being easier to access for HCPs. As there were documents that were not classed as medical changes identified, the information regarding what is acceptable to be included in that section needs to be made clearer to the HCPs. The findings from this study can be further developed and used as a reference for future studies on this subject.

Hepatocellular carcinoma (HCC) causes ~ 600,000 deaths annually, making it the second most deadly cancer form. HCC is classified into five stages and for the intermediate HCC treatment, the two most commonly used drug delivery systems (DDSs) are lipiodol-based emulsions and drug-eluting beads. The aims of this thesis were to develop in vitro methods suitable for studying these DDSs. It is important to investigate the release mechanisms and release rates with relevant in vitro methods, as this can improve the understanding of the in vivo performance. Miniaturized in vitro methods with sample reservoirs separated from the release medium by a diffusion barrier were developed and shown to be suitable for studying drug release from particle DDSs (Paper I). In Paper II these methods were further developed and used to study the release of doxorubicin (DOX) from the clinically used drug-eluting beads. DOX release rates were affected by the method set-up and the characteristics of the release medium. The choice of method and volume of release medium could improve the in vivo-likeness of the in vitro release profiles. Applied theoretical models suggested a film-controlled type of DOX release mechanism from the beads when self-aggregation, DOX-bead interaction, and DOX deprotonation were taken into account.

A micropipette-assisted microscopy method was used to further improve the understanding of the release mechanism of amphiphilic molecules from the beads (Paper III). A detailed analysis suggested an internal depletion-layer model dependent on molecular self-aggregation for the release. It was further suggested that a simple ion-exchange mechanism is unrealistic in physiological conditions.

The important pharmaceutical factors for the emulsion-based formulations were investigated in Paper IV. DOX solubility, lipid phase distribution, and emulsion stability increased when the contrast agent iohexol was added. Also, an increase in release half-life (h) was observed from emulsions with iohexol.

The in vitro methods and theoretical models presented in this thesis can be used during development and optimization of future DDSs.

Microgels, such as polymeric hydrogels, are currently used as drug delivery devices (DDSs) for chemotherapeutics and/or unstable drugs. The clinical DDS DC bead® was studied with respect to loading and release, measured as relative bead-volume, of six amphiphilic molecules in a micropipette-assisted microscopy method. Theoretical models for loading and release was used to increase the mechanistic understanding of the DDS.

It was shown that equilibrium loading was independent of amphiphile concentration. The loading model showed that the rate-determining step was diffusion of the molecule from the bulk to the bead surface (‘film control’). Calculations with the developed and applied release model on the release kinetics were consistent with the observations, as the amphiphiles distribute unevenly in the bead. The rate determining step of the release was the diffusion of the amphiphile molecule through the developed amphiphile-free depletion layer. The release rate is determined by the diffusivity and the tendency for aggregation of the amphiphile where a weak tendency for aggregation (i.e. a large cac_b) lead to faster release. Salt was necessary for the release to happen, but at physiological concentrations the entry of salt was not rate-determining. This study provides valuable insights into the loading to and release from the DDS. Also, a novel release mechanism of the clinically used DDS is suggested.

Transarterial chemoembolization with emulsion-based formulations using doxorubicin hydrochloride (DOX) and Lipiodol (R) is the golden standard for the loco-regional treatment of unresectable hepatocellular carcinoma (HCC). However, from a pharmaceutical quality perspective these emulsions are poorly characterized. In this study, clinically relevant Lipiodol (R)-based emulsions were characterized in terms of emulsion stability, continuous phase classification and droplet-size distribution. Also, the solubility of DOX in the different emulsion components and the distribution of DOX to the lipid phase were investigated. These are key features to investigate due to the claimed tumor-seeking properties of Lipiodol (R). The in vitro release of DOX was studied in a miniaturized dialysis method and an empirical release model was applied to adjust for the passage of DOX across the dialysis membrane. The most stable emulsion ( > 72 h) was classified as water-in-oil (w/o), had the highest distribution of DOX to the lipid phase (20%) and an aqueous-to-lipid phase ratio of 1:4. The composition of the aqueous phase was a mixture (v/v) of iohexol (85%) and water (15%). Emulsions containing iohexol and a high aqueousto-lipid phase ratio (1:2-1:4) displayed prolonged in vitro release profiles of DOX. This study further emphasizes the medical need to standardize these emulsion-based drug delivery systems.

We have evaluated a miniaturized in vitro method, based on the mDISS Profiler (TM) technique that enables on-line monitoring of drug release from a 21 mu l sample with 10 ml of release medium. Four model drugs in eight clinically used formulations, including both solid and non-solid drug delivery systems, were investigated. The acquired data were compared with historical in vitro release data from the same formulations. Use of the Weibull function to describe the in vitro drug-release profiles allowed discrimination between the selected formulations with respect to the drug-release mechanisms. Comparison of the release data from the same formulation in different in vitro set-ups showed that the methodology used can affect the mechanism of in vitro release. We also evaluated the ability of the in vitro methods to predict in vivo activity by comparing simulated plasma concentration-time profiles acquired from the application of the biopharmaceutical software GI-Sim to the in vitro observations. In summary, the simulations based on the miniaturized-method release data predicted the plasma profiles as well as or more accurately than simulations based on the historical release data in 71% of the cases and this miniaturized in vitro method appears to be applicable for both solid and non-solid formulations.

The release rate of doxorubicin (DOX) from the drug-delivery system (DDS), DC Bead, was studied by 2 miniaturized in vitro methods: free-flowing and sample reservoir. The dependencies of the release mechanisms on in vitro system conditions were investigated experimentally and by theoretical modeling. An inverse relationship was found between release rates and bead size, most likely due to the greater total surface area. The release rates correlated positively with temperature, release medium volume, and buffer strength, although the release medium volume had larger effect than the buffer strength. The sample reservoir method generated slower release rates, which described the in vivo release profile more accurately than the free-flowing method. There was no difference between a pH of 6.3 or 7.4 on the release rate, implying that the slightly acidic tumor microenvironment is less importance for drug release. A positive correlation between stirring rate and release rate for all DDS sizes was observed, which suggests film controlled release. Theoretical modeling highlighted the influence of local equilibrium of protonation, self-aggregation, and bead material interactions of DOX. The theoretical release model might describe the observed larger sensitivity of the release rate to the volume of the release medium compared to buffer strength. A combination of miniaturized in vitro methods and theoretical modeling are useful to identify the important parameters and processes for DOX release from a micro gel-based DDS.

Abstract

Background Clofazimine is a repurposed drug to treat multidrug-resistant tuberculosis (MDR-TB) and is also a cornerstone of leprosy treatment. Pharmacokinetic (PK) data of clofazimine is scarce, but a population pharmacokinetics (popPK) model of clofazimine developed on data from South African MDR-TB patients has been published. Body composition was reported to be the key covariate that impacted both drug disposition and exposure. 

Aim The aim of this master research work was to re-evaluate and optimize the published popPK model of clofazimine in Indonesian patients with MDR-TB.

Methods The pre-existing model from South Africa was used as starting point and fitted to PK data from Indonesian, 49 patients with clofazimine based treatment over 4 months. The model was evaluated and adjusted to optimize its performance. The PK parameters were estimated and accumulation of clofazimine was examined. 

Results The model estimated a large central volume of 100 L and a clearance of 11.7 L/h, the median terminal half-life was about 20 days and substantial accumulation was observed over the 4 months. Women had much longer half-life and thereby slower accumulation and lower exposures due to high body fat in comparison with men. A large variability between occasions and subjects was detected.

Conclusion The model was able to describe the central tendency of the data well, but overpredicted the random variability between patients. That could be a results of participants adherence issues or varying food intake along with the drug during the treatment. This should be investigated in future analyses to get more reliable results.

Bakgrund: Gastric bypass är en operationsmetod som leder till en fysiologisk förändring i magtarmkanalen av perorala läkemedel, i syfte till att främja viktnedgång. Tidigare studier har stärkt teorin om att ett förändrat upptag av två vanligt förekommande läkemedel i kliniken, levotyroxin och omeprazol, sker som en följd av gastric bypass operation. Absorptionen av dessa läkemedel är kliniskt relevanta då den terapeutiska effekten är avgörande för behandlingen och därmed hälsan hos en bred patientgrupp inom sjukvården. 

Syfte: Syftet med denna litteraturstudie är att reda ut hur absorptionen av levotyroxin och omeprazol påverkas efter en gastric bypass operation. 

Metod: Detta är en litterturstudie baserat på åtta orginalstudier, fyra om läkemedlet omeprazol och fyra studier om läkemedlet levotyroxin. Artiklarna identifierades efter sökningar i PubMed och Embase under april 2021. Inklusionskriterier var gastric bypass som operationsmetod samt att publikationsdatumet är inom de senaste 20 åren. Barn, äldre och patienter med samtidigt vitaminkonsumtion exkluderades. 

Resultat: Av levotyroxinartiklarna konkluderar två av dessa att en minskad absorption av läkemedlet sker efter gastric bypass. De två resterande artiklar redovisade ingen förändring gällande absorptionen. Artiklar som studerade levotyroxin upptaget i form av flytande beredning efter gastric bypass, påvisade ökat läkemedelsupptag i flytande form gentemot tablettform. I de fyra artiklar som studerades omeprazol och dess absorption, styrktes en minskad läkemedlsabsorption i två av de artiklarna, samt en observerad avsaknad av signifikant skillnad i de två resterande artiklarna. 

Slutsats: Ett fullständigt svar till frågeställningen om levotyroxin coh omeprazol leder till minskat läkemedelsupptag efter gastric bypass, kan inte återfås av denna litterturstudie på grund av motstridiga resultat. Detta resultat indikerar däremot behovet av en individuell farmakoterapi då variationen mellan olika individer gällande faktorer såsom BMI och kön, kan påverka läkemedelsupptaget. 

The inoculum effect (i.e., reduction in antimicrobial activity at large starting inoculum) is a phenomenon described for various pathogens. Given that limited data exist regarding inoculum effect of Acinetobacter baumannii, we evaluated killing of A. baumannii by polymyxin B, a last-resort antibiotic, at several starting inocula and developed a pharmacokinetic-pharmacodynamic (PKPD) model to capture this phenomenon. In vitro static time-kill experiments were performed using polymyxin B at concentrations ranging from 0.125 to 128 mg/L against a clinical A. baumannii isolate at four starting inocula from 10(5) to 10(8) CFU/mL. Samples were collected up to 30 h to quantify the viable bacterial burden and were simultaneously modeled in the NONMEM software program. The expression of polymyxin B resistance genes (lpxACD, pmrCAB, and wzc), and genetic modifications were studied by RT-qPCR and DNA sequencing experiments, respectively. The PKPD model included a single homogeneous bacterial population with adaptive resistance. Polymyxin B effect was modeled as a sigmoidal E-max model and the inoculum effect as an increase of polymyxin B EC50 with increasing starting inoculum using a power function. Polymyxin B displayed a reduced activity as the starting inoculum increased: a 20-fold increase of polymyxin B EC50 was observed between the lowest and the highest inoculum. No effects of polymyxin B and inoculum size were observed on the studied genes. The proposed PKPD model successfully described and predicted the pronounced in vitro inoculum effect of A. baumannii on polymyxin B activity. These results should be further validated using other bacteria/antibiotic combinations and in vivo models.