To Evaluate the Effect of Mirabegron (YM178) on Blood Levels of Desipramine When They Are Taken Together

Inclusion Criteria: * Body Mass Index between 18.5 and 30.0 kg/m2 inclusive * Subject is genotyped and phenotyped as an extensive metabolizer for CYP2D6 Exclusion Criteria: * Known or suspected hypersensitivity to YM178 or any of the components of the formulation used * Known or suspected hypersensitivity to desipramine or any of the components of the formulation used * Pregnant or breast feeding within 6 months before screening assessment * Any clinical history of major depressive disorder, cardiovascular disease, urinary retention, glaucoma, thyroid disease and/or seizure disorder * Any of the liver function tests (i.e. Alanine Aminotransferase (ALT), Asparate Aminotransferase (AST) and Alkaline phosphatase) above the upper limit of normal at repeated measurements * Any clinically significant history of asthma, eczema, any other allergic condition or previous severe hypersensitivity to any drug (excluding non-active hay fever) * Any clinically significant abnormality following the investigator's review of the pre-study physical examination, ECG and clinical laboratory tests * Abnormal pulse rate and/or blood pressure measurements at the pre-study visit as follows: pulse rate \<40 or \>90 bpm; mean systolic blood pressure \>140 mmHg; mean diastolic blood pressure \>90 mmHg (blood pressure measurements taken in triplicate after subject has been resting in supine position for 5 min; pulse rate will be measured automatically) * A marked baseline prolongation of QT/QTc interval after repeated measurements of \>450 ms, a history of unexplained syncope, cardiac arrest, unexplained cardiac arrhythmias or torsades de pointes, structural heart disease, or a family history of Long QT Syndrome (LQTS)