The objective of this study is to develop an exploratory design for future Proof-of-Concept trials which reliably and accurately measure the central nervous system (CNS) effects of potentially new drugs that oppose the effects of ketamine at a subanesthetic dose level given to healthy volunteers. A functional magnetic resonance imaging (fMRI) and electroencephalogram (EEG) performed simultaneously during a ketamine challenge will register the effects triggered by Ketamine.
This will be a double-blind (neither physician nor patient knows the name of the assigned drug), placebo-controlled, randomized (study drug assigned by chance), 2 way crossover ketamine challenge study (participants may receive different interventions sequentially during the trial) in 24 healthy male volunteers. For all participants, this study will consist of an eligibility screening examination, two 2-day treatment periods, separated by at least 1 week, and a follow-up examination about 7 days after last dose administration. The maximal study participation for each volunteer will be around 6 weeks. Apart from observing possible neural and vascular ketamine effects, the cerebral ketamine effects will be investigated by simultaneously performing fMRI/EEG during ketamine administration. These investigations will be done while volunteers rest as well as during cognitive testing (visual oddball task). Safety evaluations include continuous monitoring of vital signs and oxygen saturation. Due to the pharmacokinetic properties of ketamine the assessments will start after an intravenous ketamine bolus (drug given directly into the vein over a short period of time) followed by a 1 minute break. During the assessments there is a continuous intravenous (minimal) drug administration. Before the assessments start there will be an intravenous bolus of 0.1 mg/kg ketamine in 5 minutes time followed by a 1 minute break after which a continuous infusion will start of 0.015625 mg/kg/min ketamine. Since the plasma level elevates during the infusion the administered dose will be lowered by 10% every 10 minutes.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
DOUBLE
Enrollment
24
An intravenous bolus will be given in 5 minutes time followed by a 1 minute break after which a continuous infusion will start. Dosage lowered every 10 minutes
An intravenous bolus of 0.1 mg/kg will be given in 5 minutes followed by a 1 minute break after which a continuous infusion will start at 0.015625 mg/kg/min.
Cerebral activation of ketamine as determined by functional MRI
Time frame: 25 and 40 minutes after end of bolus injection of ketamine/placebo
Cerebral activation of ketamine as determined by electroencephalogram (EEG) during an oddball-task
Time frame: 25 and 40 minutes after end of bolus injection of ketamine/placebo
Effect of Ketamine on consciousness as measured by the "Altered States of Consciousness Rating Scale"
Time frame: 60 min after end of bolus injection of ketamine.
Cerebral activation induced by ketamine as measured by simultaneous fMRI / EEG under resting conditions
Time frame: 0 and 25 min after end of bolus injection of ketamine.
Symptom score of ketamine as measured with the Positive And Negative Symptom Scale
Time frame: 60 min after end of bolus injection of ketamine (= at the end of ketamine infusion).
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.