The primary purpose of this study is to determine the effect of repeated administration of itraconazole on the pharmacokinetic (PK) profile of S-309309; and the PK of S-309309 following administration of S-309309 alone and co-administration with itraconazole

Key Inclusion Criteria:

• Participants who are considered to be medically healthy as determined by the investigator
• Participants whose body mass index (BMI) is within the range of ≥ 18.5 to ≤ 30.0 kg/m^2
• Contraceptive use by male and female participants should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies
• Participants who understand the study procedures and agree to participate by providing written informed consent
• Participants who are willing and able to comply with all study procedures and restrictions

Key Exclusion Criteria:

• Participants who have a history of clinically significant hypersensitivity or severe side effects induced by a drug.
• Participants who have a history of ventricular dysfunction, congestive heart failure, or pulmonary edema.
• Participants who have a history of gastrointestinal surgery including, but not limited to, cholecystectomy, gastric resection, and/or intestinal resection that may result in a clinically significant abnormality in gastrointestinal function (except for an appendectomy). Participants can be considered by the investigator (or sub-investigator) to be ineligible for the study due to a history of or current condition of significant metabolic or endocrine, hepatic, renal, hematological, pulmonary, cardiovascular, gastrointestinal, urological, immunological, neurological, or psychiatric disorders with clinical manifestations.
• Participants who are considered inappropriate for participation in the study for any reason by the investigator (or sub-investigator).

Note: Other protocol defined Inclusion/Exclusion criteria may apply.