Effect of TAK-954 on Gastrointestinal and Colonic Transit in Diabetic or Idiopathic Gastroparesis Participants

The drug being tested in this study is called TAK-954. TAK-954 is a 5 HT4 receptor agonist
and is being tested to treat people who have diabetic or idiopathic gastroparesis and who
previously reported delay in stomach emptying. This study will look at the gastric emptying
time of solids in people who take TAK-954 or placebo.

The study will enroll approximately 41 participants. Participants will be randomly assigned
(by chance, like flipping a coin) to one of the four treatment groups-which will remain
undisclosed to the participant and study doctor during the study (unless there is an urgent
medical need):

- TAK-954 0.1 mg

- TAK-954 0.3 mg

- TAK-954 1 mg

- Placebo (dummy inactive solution) - this is a solution that looks like the study drug
but has no active ingredient.

During the study, participants will complete a daily diary to record their bowel habits and
determine the severity of their gastroparesis symptoms using the Gastroparesis Cardinal
Symptom Index (GCSI).

This single center trial will be conducted in the United States. The duration of treatment is
3 days and the overall period of evaluation is up to 28 days. The participants will be
contacted by telephone (Days 10 to 14) for follow-up assessment. There will be another
follow-up phone call for women of childbearing potential (Days 38 to 43).

Inclusion Criteria:

1. Has diabetes mellitus with symptoms of gastroparesis and previously documented gastric
emptying delay or previously documented idiopathic gastroparesis in the last 5 years.

2. Has a body mass index (BMI) greater than or equal to (>=) 16 and less than or equal to
(<=) 40 kilogram per square meter (kg/m^2) at the Screening Visit.

Exclusion Criteria:

1. Has glycosylated hemoglobin (HbA1c) greater than (>) 12 percent (%).

2. Has other structural diseases/conditions that affect the gastrointestinal (GI) system.

3. Are unable to withdraw drugs known to alter GI transit 48 hours prior to the study.

4. Has clinically significant abnormal baseline safety laboratory values.

5. Has preexisting hepatic disease that meets Child-Pugh Class B (moderate; total score 7
to 9 points) or C (severe; total score 10 to 15 points).

6. Are without known preexisting hepatic disease who have 1 or more of the following:

- AST or ALT >2 times the upper limit of normal (ULN).

- Bilirubin >1.5 times the ULN unless due to Gilbert's syndrome.

- International normalized ratio (INR) >1.5 unless on anticoagulation therapy.

7. Has QT intervals with Fridericia correction method (QTcF) interval (>=) 460
millisecond (msec) or with other factors that increase the risk of QT prolongation or
arrhythmic events at screening. Note: Participants with bundle branch block and a
prolonged QTc interval, or with QTcF between 450 and 460 msec, should be reviewed by
the Medical Monitor for potential inclusion.

8. Has second or third degree atrioventricular (AV) block; AV disassociation; >5 beats of
non-sustained VT at a rate >120 beats per minute (bpm); Electrocardiogram (ECG)
changes consistent with acute myocardial ischemia or infarction.

9. Has cardiac history that includes conditions requiring heart rate control (example,
atrial fibrillation, atrial flutter, ventricular tachycardia, or other
tachyarrhythmias).

10. Has clinical evidence (including physical examination, ECG, clinical laboratory value
and review of the medical history) of significant cardiovascular, respiratory,
moderate or severe renal insufficiency (creatinine clearance <=60 mL/min),
hematological, neurological, or psychiatric disease, or other disease that interferes
with the objectives of the study.

11. If female, are pregnant or lactating or intending to become pregnant before
participating in this study, during the study, and 4 to 5 days (5 half-lives) PLUS 30
days after last dose of the study drug; or intending to donate ova during such time
period.

12. Are considered by the investigator to be alcoholics not in remission or known
substance abusers. Have a history of alcohol consumption exceeding 2 standard drinks
per day on average (1 glass is approximately equivalent to: beer [354 milliliter per
[mL/] 12 ounces], wine [118 mL/4 ounces], or distilled spirits [29.5 mL/1 ounce] per
day).