The purpose of this study is to evaluate the dose strength equivalence of to-be-marketed (TBM) centanafadine (CTN) once daily (QD) extended release (XR) when administered as 2 capsules of 164.4 milligrams (mg) or as a single capsule of 328.8 mg, effect of food on the absorption of the TBM CTN QD XR capsule, and relative bioavailability of clinical (Clin) CTN sustained release (SR) tablets to the TBM CTN QD XR capsules.

Inclusion Criteria:

1. Body mass index (BMI) between 19.0 to 32.0 kilograms per square meter (kg/m^2) (inclusive).

2. In good health as determined by:

   • Medical history
   • Physical examination
   • Electrocardiogram (ECG)
   • Serum/urine chemistry, hematology, and serology tests.

3. Ability to provide written, informed consent prior to initiation of any trial-related procedures, and ability, in the opinion of the investigator, to comply with all the requirements of the trial.

Exclusion Criteria:

1. Clinically significant abnormality in past medical history, or at the screening physical examination, that in the investigator's or sponsor's opinion may place the participant at risk or interfere with outcome variables including absorption, distribution, metabolism, and excretion of drug. This includes, but is not limited to, history of or concurrent cardiac, hepatic, renal, neurologic, endocrine, gastrointestinal, respiratory, hematologic, and immunologic disease or cholecystectomy.
2. History of drug and/or alcohol abuse within 2 years prior to screening.
3. History of or current hepatitis or AIDS or carriers of hepatitis B surface antigen (HBsAg) and/or hepatitis C antibodies (anti-HCV), or HIV antibodies.
4. History of any significant drug allergy or known or suspected hypersensitivity.
5. A positive urine or breath alcohol test and/or urine drug screen for substance of abuse at screening or upon admission to the trial site.
6. Any participant who, in the opinion of the investigator, should not participate in the trial.

Note: Other protocol-specified Inclusion/Exclusion criteria may apply.

Anonymized individual participant data (IPD) that underlie the results of this study will be shared with researchers to achieve aims pre-specified in a methodologically sound research proposal. Small studies with less than 25 participants are excluded from data sharing.

Data will be available after marketing approval in global markets, or beginning 1-3 years following article publication. There is no end date to the availability of the data.

Otsuka will share data on the Vivli data sharing platform: https://vivli.org/ourmember/Otsuka/