This thesis describes a set of excitability measurements -transcranial magnetic stimulation (TMS) combined with electromyography (EMG) and electroencephalography (EEG), nerve excitability threshold... Show moreThis thesis describes a set of excitability measurements -transcranial magnetic stimulation (TMS) combined with electromyography (EMG) and electroencephalography (EEG), nerve excitability threshold tracking (NETT), and muscle velocity recovery cycles (MVRC)- and the applicability of these tools in early phase clinical drug development. We validated the biomarkers in healthy subjects with registered drugs and showed that the measurements are all repeatable and sensitive to pharmacological effects, even in a small number of subjects. Furthermore, we have evaluated effects of a novel AMPA-positive allosteric modulator with TMS-EMG/EEG, and a first-in-class skeletal muscle-specific chloride channel (ClC-1) inhibitor with MVRC, and the findings helped us to confirm proof-of-mechanism of these compounds in healthy subjects. In conclusion, these measurements proved to be valuable pharmacodynamic biomarkers in two drug development programs, encouraging their further use in clinical development of other future drug candidates targeting cortical-, neuronal-, and muscle cell excitability. The use of such clinical pharmacodynamic biomarkers could improve the quality and efficiency of the development process of drugs for e.g. amyotrophic lateral sclerosis, chronic pain, depression, treatment-resistant epilepsy, and neuromuscular diseases. Show less
In this thesis the development of a pathophysiology-based method for the early evaluation of anthracycline-induced cardiotoxicity was described. We evaluated a comprehensive array of biomarkers,... Show moreIn this thesis the development of a pathophysiology-based method for the early evaluation of anthracycline-induced cardiotoxicity was described. We evaluated a comprehensive array of biomarkers, representing several aspects of anthracycline-induced cardiotoxicity, including cardiac injury and remodeling, free radical overload and the inflammation accompanying the injury. It was shown that predominantly the markers of cardiac injury may be suitable for the early detection of anthracycline-induced cardiotoxicity. In the second part of this thesis we evaluated a new, free-radical scavenging compound against anthracycline-induced cardiotoxicity using this approach. The failure of this compound to show efficacy against anthracycline-induced cardiotoxicity in our model suggests that a broader approach toward the mechanism of anthracycline-induced cardiotoxicity is necessary Show less