A Phase 2 Study to Evaluate Pharmacodynamics of YKP10811 in Patients With Chronic or Functional Constipation

If the participant fulfills the initial eligibility criteria, the patient will be randomized
to 1 of the active treatment groups or placebo. During the treatment period, patients will
receive study medication once daily for 8 days. Patients will undergo scintigraphic
assessment of gastric, small bowel and colonic transit of solids over the 48-hour period.

Patients will be males or females, 18 through 65 years of age with a body mass index (BMI)
of 19 through 40 kg/m2, with Chronic Constipation or Functional Constipation and no evidence
of evacuation disorder as assessed by the Investigator and meet all the inclusion criteria
and none of the exclusion criteria.

Inclusion Criteria:

1. Non-smokers (refrained from any tobacco or nicotine usage, including smokeless
tobacco, nicotine patches, etc.) for at least 6 months prior to Day 1 of the study

2. Body Mass Index of 19 through 40 kg/m2

3. Participants must be willing to follow dietary restrictions

4. Females of childbearing potential (ie, not menopausal, no hysterectomy, no bilateral
oophorectomy) must complete a negative pregnancy test (urine) prior to receiving any
radioisotopes

5. No evidence of pelvic floor dysfunction

6. If clinically indicated, absence of an evacuation disorder should be confirmed within
30 days prior to the first dose of study medication

7. At Screening, patients must meet ROME III Criteria for FC, which assumes an absence
of a structural or biochemical explanation

8. The patient's screening (baseline) colonic transit test must show a GC ≤ 2.4 at 24
hours; and

9. Baseline EKG shows QTc interval ≤ 450mSec

Exclusion Criteria:

1. History of clinically-significant manifestations or current abnormality of any organ
system

2. History of inflammatory bowel disease

3. Any history of GI surgery within 6 months prior to the first dose of study medication

4. History of clinically-significant prolonged diarrhea, in the absence of a laxative

5. Patients who have started a special dietary habit and/or an intense physical workout
program within 4 weeks prior to the first dose of study medication

6. Any clinically-significant surgical procedure within 30 days prior to the first dose
of study medication

7. History of alcoholism or drug addiction within 12 months prior to the first dose of
study medication

8. Any patient who has had an acute illness within 5 days prior to the first dose of
study medication, eg, flu syndrome, GI virus, indigestion

9. Patients who are breastfeeding