Investigation of Tolterodine, Pregabalin and a Tolterodine - Pregabalin Combination for the Treatment of Overactive Bladder

• Drug: Tolterodine & Pregabalin
  
  Tolterodine SR Oral, 2mg, once daily for 4 weeks Pregabalin, Oral, 75 mg, twice daily for 4 weeks
• Drug: Tolterodine
  
  Tolterodine SR, Oral, 4 mg, once daily for 4 weeks
• Drug: Placebo
  
  Placebo, Oral, twice daily for 4 weeks
• Drug: Tolterodine & Pregabalin
  
  Tolterodine SR Oral, 4mg, once daily for 4 weeks Pregabalin, Oral, 150 mg, twice daily for 4 weeks
• Drug: Pregabalin
  
  Pregabalin, Oral, 150 mg twice daily for 4 weeks

• Experimental: A
  
  Tolterodine SR 2 mg once daily combined with pregabalin 75 mg twice daily
  Intervention: Drug: Tolterodine & Pregabalin
• Active Comparator: B
  
  Tolterodine SR 4 mg once daily
  Intervention: Drug: Tolterodine
• Placebo Comparator: C
  
  Placebo
  Intervention: Drug: Placebo
• Experimental: D
  
  Tolterodine SR 4 mg once daily combined with pregabalin 150 mg twice daily
  Intervention: Drug: Tolterodine & Pregabalin
• Experimental: E
  
  Pregabalin 150 mg twice daily
  Intervention: Drug: Pregabalin

Inclusion Criteria:

• Women > 18 years Old
• Diagnosis of OAB (micturition frequency >/= 8 times per day; urinary urgency >/= 4 times per week)

Exclusion Criteria:

• Subjects with symptoms of overactive bladder for less than 6 months prior to randomization.
• Significant stress incontinence as determined by the investigator e.g. stress predominant mixed incontinence, positive cough provocation test.
• Subjects with any condition that would contraindicate the use of tolterodine or pregabalin, including: Uncontrolled narrow angle glaucoma; Urinary retention; Myasthenia gravis; Gastric retention; Severe ulcerative colitis; Toxic megacolon; Rare hereditary problems of galactose intolerance; Fructose intolerance; Sucrose-isomalate insufficiency; Lapp lactase deficiency; Glucose-galactose malabsorption.