A Clinical Study to Determine the Effect of YM178 on the Pharmacokinetics of Warfarin in Healthy Subjects

• R- and S-warfarin in plasma: AUCinf, AUClast, Cmax, tmax, t1/2, CL/F [ Time Frame: Day 1-9 and 15-31 ] [ Designated as safety issue: No ]
• The AUCinf of both enantiomers will be used to assess the potential drug-drug interaction. [ Time Frame: Day 1/2 and 15/16 ] [ Designated as safety issue: No ]

• Adverse events, clinical laboratory tests (hematology, biochemistry, urinalysis), vital signs, 12-lead ECG, physical examination [ Time Frame: Day -1 - 31 ] [ Designated as safety issue: Yes ]
• YM178 in plasma: Ctrough, AUCtau, Cmax, tmax, CL/F [ Time Frame: Day 20-24 ] [ Designated as safety issue: No ]
• Degree of anticoagulation: AUCPT;0-168h (area under the prothrombin time versus time curve from 0 to 168 h after dosing with warfarin), AUCINR;0-168h, maximum PT (PTmax), time to reach PTmax (tPT; max), INRmax, tINR;max [ Time Frame: Day 1-9 and 23-31 ] [ Designated as safety issue: No ]

This study investigates whether YM178 has an effect on the pharmacokinetics of warfarin, to exclude any drug-drug interaction between YM178 and warfarin, and evaluates the safety and tolerability of warfarin alone and combined with YM178.

• Drug: warfarin
  Oral
  Other Name: Coumadin
• Drug: YM178
  Oral
  Other Name: mirabegron

Inclusion Criteria:

• Female subject must be of non-child bearing potential, i.e. postmenopausal, surgically sterilized (e.g. tubal ligation), hysterectomy in medical history, or must practice adequate (double barrier) non-hormonal contraceptive methods to prevent pregnancies.
• Body Mass Index (BMI) ≥ 18.5 and < 30 kg/m2, inclusive

Exclusion Criteria:

• Female who is pregnant
• Any of the liver function tests (i.e. alanine aminotransferase (ALT), aspartate aminotransferase (AST) and Alkaline Phosphatase (AP)) above the upper limit of normal (ULN)
• Any clinically significant history of disease or disorder - gastrointestinal, cardiovascular, respiratory, renal, hepatic, neurological, dermatological, psychiatric or metabolic as judged by the medical investigator
• Abnormal pulse and/or blood pressure measurements and the pre-study as follows: Pulse < 40 or > 90 bpm; mean systolic blood pressure > 140 mmHg; mean diastolic blood pressure > 90 mmHg (blood measurements taken in triplicate after subject has been resting in supine position for 5 min; pulse 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)
• Use of any prescribed or OTC (over-the counter) drugs (including vitamins, natural and herbal remedies, e.g. St. John's wort) in the 2 weeks prior to admission to the Clinical Unit, except for paracetamol (up to 3 g/day)
• Any use of drugs of abuse within 3 months prior to admission to the clinical unit
• History of smoking more than 10 cigarettes (or equivalent amount of tobacco) per day within 3 months prior to admission to the clinical unit
• History of drinking more than 21 units of alcohol per week (1 unit = 270 ml of beer or 40 ml of spirits or 1 glass of wine) (> 14 units of alcohol for female subjects) within 3 months prior to admission to the clinical unit
• Donation of blood or blood products within 3 months prior to admission to the clinical unit