A Study of the Safety and Effectiveness of DDP733 in Treating IBS With Constipation in Females

Inclusion Criteria:

- Female from 18 to 65 years of age, inclusive

- Patient experiences recurrent abdominal pain or discomfort at least 3 days per month
for the last 3 months with symptom onset at least 6 months prior to diagnosis. The
patient's symptoms must be associated with 1 or more of the following:

- Improvement with defecation

- Onset associated with a change in frequency of stool

- Onset associated with a change in form (appearance) of stool

- Negative serum and urine pregnancy tests

- Completion of at least six days of daily diary assessments using a phone-in
information system prior to randomization

Exclusion Criteria:

- Serious underlying diseases, including psychiatric disorders

- Current history of conditions affecting bowel transit

- Recent history of biochemical or structural abnormalities of the gastrointestinal
tract, gastrointestinal surgery, or gastrointestinal infection

- Clinically significant abnormal examination findings or laboratory tests

- Inability to stop taking certain medications, or a planned change in medications
(including herbal remedies) which could interfere with study assessments

- Use of drugs and or ethanol which may interfere with compliance of study procedures
or influence study outcome

- Presence of a medical condition which could interfere with the interpretation of
study data

- Significant use of nicotine or caffeine