A study to compare the pharmacokinetics of tamsulosin HCl and solifenacin succinate after co-administration of single entity tablets and of the combination tablet EC905 under steady state conditions at three dose strengths.

There will be 3 dose cohorts of 15 subjects each. In Period 1, subjects will be randomized to either receive multiple doses of both tamsulosin HCl and solifenacin succinate as single entity tablets, or the combination tablet EC905. The alternate treatment will be provided in Period 2. The cohorts will be balanced for period effects and first-order carry over effects.

Inclusion Criteria:

• Body Mass Index between 18.5 and 30.0 kg/m2.

Exclusion Criteria:

• Known or suspected hypersensitivity to tamsulosin HCl, solifenacin succinate, EC905 or any of the components of the formulations used.
• Any of the liver function tests 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 other drug (excluding non-active hay fever).
• Subject is at risk of urinary retention based on medical history.
• A planned cataract surgery within 30 days after completion of the study.
• 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 >160 mmHg; mean diastolic blood pressure >100 mmHg (blood pressure 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 occasional use of paracetamol (up to 3 g/day).
• Regular use of any inducer of liver metabolism (e.g. barbiturates, rifampin) in the 3 months prior to admission to the Clinical Unit.
• 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 cc of beer or 40 cc of spirits or 1 glass of wine) 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.
• Positive serology test for HBsAg, anti HAV (IgM), anti-HCV or anti-HIV 1+2.
• Participation in any clinical study within 3 months or participation in more than 3 clinical studies within 12 months, prior to the expected date of enrolment into the study, provided that the clinical study did not entail a biological compound with a long terminal half-life. An exception is (partly) participation in Astellas study 905-CL-071, provided a washout of at least 12 days is considered prior to re-enrolment.
• Employee of the Astellas Group or CRO involved in the study.