A Phase 1, Single-Center, Randomized, Double-blind, Placebo-Controlled Study to Evaluate the Safety, Pharmacokinetics, and Pharmacodynamics of Single Ascending and Multiple Dose of TS-172 in Healthy Adult Subjects

Inclusion Criteria:

1. Japanese healthy males aged 20 years or older but less than 40 years at the time of informed consent
2. Those with a BMI of 18.5 or more and less than 25.0 at screening test
3. Those who are able to receive the explanation before participating in the study, understand the content of the study, and provide written informed consent by the subjects themselves.

Exclusion Criteria:

1. Subjects who have any disease and are not considered healthy subjects based on the medical judgment of the principal investigator or sub-investigator.

2. Those who correspond to any of the following about bowel movements;

   • Repeated diarrhea (Bristol Stool Form Score [BSFS] score of 6 or higher) on a daily basis
   • Repeated constipation (no defecation for 2 days or more in a week) on a daily basis

3. Those who correspond to any of the following about bowel movements in the 7 days before administration;

   • Diarrhea on 2 or more days in 7 days
   • 2 or more days without a bowel movement in 7 days

4. Those who have a history of gastrointestinal ulceration

5. Those who correspond to any of the following about infection;

   • Positive for SARS-CoV-2 in the nucleic acid amplification test performed at the time of admission
   • Suspected of having COVID-19