Single Dose Two-periods Crossover Bioequivalence Study of Darifenacin Tablets in Healthy Volunteers.

Inclusion Criteria: * Healthy male or female subjects 18 to 50 years of age (inclusive) * In good health, as determined by lack of clinically significant abnormalities at screening as judged by the physician. * Female subjects are required to use a medically accepted method of hormonal contraception or abstinence throughout the entire study period and for one week after the study is completed. * Body mass index within the range of 18.5 and 29.9 kg/m2 and weight at least 45 kg. Exclusion Criteria: * Known hypersensitivity or severe adverse event to darifenacin or similar drugs. * Urinary retention, narrow-angle glucoma, myasthenia gravis, severe hepatic impairment, severe ulcerative colitis, toxic megacolon. * Symptomatic hiatus hernia, erosive or symptomatic gastroesophageal reflux disease/heartburn (\>2 days in a week), severe constipation, gastrointestinal obstructive disorder, and gastric retention. * Clinically significant cardiac abnormalities, fainting, low blood pressure upon standing, irregular heartbeats. * Acute or chronic bronchospastic disease (including asthma and Chronic Obstructive Pulmonary Disease). * Clinically significant drug allergy or history of atopic allergy (asthma, urticaria, eczematous dermatitis). * Smokers of more than 5 cigarettes a week. * Regular use of any drugs known to induce or inhibit hepatic drug metabolism (particularly those that affect CYP2D6) within 30 days prior to each study drug administration. * Any surgical or medical condition wich might significantly alter the absorption, distribution, metabolism or excretion of drugs which may jeopardize participation in the study. * Immunodeficiency diseases, including a positive HIV (Elisa or Western blot) test result. * Positive hepatitis B Surface antigen (HBsAg) or Hepatitis C test result. * Drug or alcohol abuse within the 6 months prior to dosing. * Use of prescription drugs within 1 month prior to dosing, or over-the-counter medication (vitamine, herbal supplements, dietary supplements) within 2 weeks prior to dosing. Paracetamol and ibuprofen are acceptable. * Participation in any clinical investigation within 4 weeks prior to dosing. * Donation or loss of 400 ml or more of blood within 2 months prior to dosing. * significant illness within 2 weeks prior to dosing. * Other protocol-defined inclusion/exclusion criteria may apply.