Influence of Liraglutide, a GLP-1 Receptor Agonist, on Brown Adipose Tissue (BAT) Activity in Humans

Inclusion Criteria: * Body mass index over 30 kg/m2. Exclusion Criteria: * Hypersensitivity to liraglutide or any of its vehicle components; * History of diabetes or pre-diabetes - either by fasting glycemia, oGTT or HbA1c; * Previous treatment within the last 3 months with glucagon like peptide-1 agonists, iDPP4 or any medication that is associated with BAT activation, including propranolol and benzodiazepines; * Liver diseases, except non-alcoholic steatohepatitis (NASH); * Infection by HIV, hepatitis B or hepatitis C; * Addiction to cannabis, heroin, morphine, cocaine, benzodiazepines or amphetamine; * Obesity induced by other disorders such as Cushing syndrome, hypothyroidism, lipodystrophy * Current or history of treatment with medications that may cause significant weight gain within 3 months prior to screening, including systemic corticosteroids (except for a short course of treatment, i.e. 7-10 days), tricyclic antidepressants, atypical antipsychotic and mood stabilizers (e.g. imipramine, amitriptyline, mirtazapine, paroxetine, phenelzine, chlorpromazine, thioridazine, clozapine, olanzapine, valproic acid and its derivatives, and lithium); * Current participation (or within the last 3 months) in an organized weight reduction program * Currently or previous using within 3 months before screening of pramlintide, sibutramine, orlistat, topiramate, or metformin (either by prescription or as part of a clinical trial) * Participation in a clinical trial within the last 3 months prior to screening * Simultaneous participation in any other clinical trial of an investigational drug * Previous surgical treatment of obesity; * Cancer (past or present, except basal cell skin cancer or squamous cell skin cancer), which in the investigator's opinion could interfere with the results of the trial * Liver enzyme (ALT and AST) above 2.5 x of reference range * Pancreatic enzymes (amylase, lipase) above 3 x the reference range * Chronic kidney disease stages 3, 4, or 5 * Relevant inflammatory or acute or chronic infectious disease; hyperthyroidism; neurological, psychiatric, gastrointestinal, respiratory, renal, hepatic or cardiac relevant disease, that could interfere with trial results per the judgment of investigator * Any condition that at the discretion of investigator could interfere with treatment adhesion on patient safety * Blood donation or transfusion within the last 3 months * Pregnancy or intention of pregnancy * History of Multiple Endocrine Neoplasia Syndrome Type 2 (MEN 2) * History of pancreatitis * Less than 80% of liraglutide adherence * Calcitonin above the reference range at the screening visit.