SMP-986 is a compound being developed for the treatment of overactive bladder syndrome (OABS). This clinical study is designed to test the hypothesis that SMP-986 at doses of 20mg, 40mg, 80mg or 120mg provides greater symptom relief in OABS compared to placebo. The hypothesis will be tested by measuring the change in mean voids/24 hrs after treatment with SMP-986 compared to placebo, as well comparing the change in: the severity of urgency episodes, mean number of urgency episodes/24 hr, mean number of incontinence episodes/24 hr and the mean void volume/void between SMP-986 and placebo.

A multicenter study conducted in patients with OABS comprising a 2-week single blind placebo run-in period followed by an 8-week randomized, double-blind, placebo controlled treatment period with patients randomized to receive 20 mg, 40 mg, 80 mg or 120 mg SMP 986 or placebo in a 1:1:1:1:1 ratio in parallel groups on an outpatient basis with study center visits.

Inclusion Criteria:

Main Inclusion Criteria:

• Males, or females who are not of child-bearing potential
• Aged 20-80 years (inclusive) with a diagnosis of OABS based on symptomatic reporting over a period of 6 months (micturition frequency, and urgency with or without incontinence) prior to screening.

Exclusion Criteria:

Main Exclusion Criteria:

• Patients will be excluded if there is an indication of any bladder outlet obstruction or polyuria

• Patients with the following conditions, or who have undergone the following procedures, will be excluded:

  • stress urinary incontinence
  • pelvic organ prolapse ( stage 2)
  • genitourinary or lower bowel surgery (within 12 months prior to screening),
  • pathological conditions including poorly controlled diabetes, painful bladder syndrome/interstitial cystitis or history of chronic urinary tract infection
  • neurological conditions including multiple sclerosis, Parkinson's disease or neuropathy)

• Patients will also be excluded if they have an indwelling catheter or perform intermittent self catheterisation

• Patients should not have a current or past medical condition contraindicating the use of antimuscarinics and must have discontinued use of the following drugs:

  • drugs used to treat OABS or urinary incontinence
  • cholinergics
  • anticholinergics
  • alpha adrenergic antagonists
  • opioid analgesics
  • compound analgesics containing an opioid
  • warfarin

• Patients with a current or past malignancy (within the last 5 years)

• Patients who have ever had a tumour affecting the genitourinary tract (not including benign prostatic hyperplasia) will be excluded.

• Patients will be ineligible if they have a clinically significant cardiac, neurological, hepatic, renal, respiratory, haematological or gastrointestinal disorder (including, a significant history of constipation or an active bowel disease e.g. inflammatory bowel disease) or any other illness which in the opinion of the Investigator would preclude the safe or compliant participation of a subject.

• Patients will be excluded if they are unable to complete the study diary