Biopharmaceuticals are among the most celebrated drugs. However, despite decades of experience, our understanding of many in vivo pharmacokinetic and adverse effects of biopharmaceuticals is... Show moreBiopharmaceuticals are among the most celebrated drugs. However, despite decades of experience, our understanding of many in vivo pharmacokinetic and adverse effects of biopharmaceuticals is still limited. These include the delay in reaching the maximum plasma concentration for an intravenously administered therapeutical protein, and the highly variable plasma concentration during elimination of monoclonal antibodies. Both observations can be explained by dynamical binding (‘stickiness’) of proteins to various (bodily) surfaces. Biopharmaceuticals also frequently contain (non-human) impurities, some of which are harmful when administered (‘dirtiness’). This toxicity often is the result of an intricate interplay of multiple cell types and effector pathways which can be difficult to simulate in the laboratory. More sophisticated test platforms are available, which can detect a number of untoward reactions that would previously not have been discovered. However, no laboratory test is fail-safe, and awareness of the possibility of adverse immunostimulation caused by biopharmaceuticals is the most important aspect for early detection and prevention of such cases in the future. Show less
The endocannabinoid system has only been discovered during the last few decades, and scientific progress in understanding the relevance of this system in health and disease has been limited and... Show moreThe endocannabinoid system has only been discovered during the last few decades, and scientific progress in understanding the relevance of this system in health and disease has been limited and slow. CB1 antagonists were considered a __miracle drug__ for the treatment of obesity and smoking with __blockbuster__ potential. But due to central side effects (such as depression and suicidal behaviour) and a lack of systematic clinical pharmacologic research, market access of a CB1 antagonists failed. In this thesis, we explored some improvements in the early development of cannabinoids, and by systematically investigating, we found that the new cannabinoid antagonist TN38837 seems effective with a reduced propensity for central side effects, and that a new oral THC formulation enhances the pharmacological activities by its seemingly superior pharmacokinetics. Also, we experiment with new methodology to optimise effect measurement, including resting state-FMRI which we found suitable for early phase cannabinoid research, and including new concentration-effect models to improve the simulation and prediction of future studies. The research in this thesis shows that a revival of research on the cannabinoid system requires novel approaches to the administration of cannabinoids, to the measurements and the study designs, and to the analyses of the effects. This reflects the complexity of the highly integrated endocannabinoid system, but also sets the stage for other innovative drug development programs Show less
This thesis covers a variety of topics around the central theme of pharmacological research involving children, with a specific focus on the development of minimally invasive methodology that can... Show moreThis thesis covers a variety of topics around the central theme of pharmacological research involving children, with a specific focus on the development of minimally invasive methodology that can be employed in future studies involving children. Children form a unique group within the area of pharmacological research and pharmacotherapy. The heterogeneity even within this group is large, covering the range of preterm neonates weighing 500 grams up to adolescents. Obviously, therapeutic needs change across this range, as among others disease epidemiology, drug disposition, pharmacodynamic response, and suitable drug formulations change with age. The same holds true for the design of drug trials involving children: where pharmacokinetics in adults can be studied simply by recruiting a number of healthy volunteers, such a study with a number of healthy toddlers is clearly not feasible and not acceptable. Therefore, approaches and new methodology are needed to circumvent these issues. Show less