The purpose of this study is to evaluate the bioequivalence of a single oral administration of a vortioxetine (Lu AA21004) 20 mg tablet in comparison with two of vortioxetine 10 mg tablets in Japanese healthy adult participants.

The drug being tested in this study is called vortioxetine (Lu AA21004). Vortioxetine is being tested in Japanese healthy adult participants. This study will look at the bioequivalence of a single oral administration of a vortioxetine 20 mg tablet in comparison with two of vortioxetine 10 mg tablets, and also look at the safety of a single oral dose of vortioxetine 20 mg in Japanese healthy adult participants.

The study will enroll 28 (14 for each sequence) healthy participants. In case bioequivalence cannot be demonstrated with the number of participants initially planned, an add-on participant study may be conducted (as a maximum 28 participants additionally). Participants will be randomly assigned (by chance, like flipping a coin) to one of the two treatment groups.

• Treatment Group A: Vortioxetine 20 mg (one 20 mg tablet) in Period 1 + Vortioxetine 20 mg (two 10 mg tablets) in Period 2
• Treatment Group B: Vortioxetine 20 mg (two 10 mg tablets) in Period 1 + Vortioxetine 20 mg (one 20 mg tablet) in Period 2

This single-center trial will be conducted in Japan. The overall time to participate in this study is approximately 25 days. Participants will make two visits to the clinic and be hospitalized for ten days in total.

Inclusion Criteria:

1. Be a healthy Japanese adult volunteer.
2. Understand the contents of the study and is capable of providing written consent to participate in the study.
3. Be willing to comply with all study procedures and restrictions.
4. Aged between ≥20 and ≤45 years at the time of screening.
5. Have a BMI of ≥18.5 and ≤24.9 (kg/m^2) and a body weight of ≥50 kg at the time of screening.
6. Be a extensive metabolizer (EM) based on CYP2D6 genotyping at the time of screening.
7. A female participant of childbearing potential with a non-sterilized male partner must agree to routinely use appropriate contraception during the study from the time of signing informed consent until 4 weeks after last dosing of the study drug.

Exclusion Criteria:

1. Has received any investigational drug within 90 days before screening for this study.
2. Previously received Lu AA21004 before participation in this study.
3. Is an employee of the sponsor or the study site, or immediate family member, or is in a dependent relationship with a study site employee who is involved in the conduct of this study (eg, spouse, parent, child, sibling) or who may be coerced to provide consent.
4. Has uncontrolled, clinically relevant neurologic, cardiovascular, pulmonary, hepatic, renal, metabolic, gastrointestinal, or endocrine disease or other abnormality which may affect study participation or study results.
5. Has a history of multiple episodes or severe allergies (eg, food, drug, latex allergy) or has had an anaphylactic reaction or significant intolerance to prescription drugs, over the counter (OTC) drugs, or foods.
6. Has a positive pregnancy test at the time of screening or Day -1.
7. Is a pregnant or lactating female.
8. Has a positive urine drug screen test at the time of screening or Day -1.
9. Has a history of drug abuse (defined as any illicit drug use) or has a history of alcohol dependence within 2 years before the start of screening or is unwilling to agree to abstain from alcohol and drugs throughout the study.
10. Consumes 6 or more servings of caffeinated beverages (containing about 120 mg of caffeine per serving) such as of coffee, tea, cola, or energy drinks.
11. Is a smoker who smoked cigarettes or used nicotine-containing products (such as nicotine patch) within 6 months before the Period 1 study drug administration.
12. Used any of the excluded drugs, dietary products or foods during the specified time periods, or will need any of them during the study period.
13. Has any current or recent gastrointestinal diseases that would be expected to influence the absorption of drugs (ie, a history of malabsorption, esophageal reflux, peptic ulcer disease, erosive esophagitis, frequent [more than once per week] occurrence of heartburn), or any surgical intervention (Stomach, cholecystectomy etc.).
14. Has a history of cancer.
15. Has a positive test result for any of the following at the time of screening: hepatitis B surface antigen (HBsAg), hepatitis C virus (HCV) antibody, human immunodeficiency virus (HIV) antibody/antigen, serological test for syphilis.
16. Has poor peripheral venous access.
17. Has undergone whole blood collection of at least 200 mL within 4 weeks (28 days) or at least 400 mL within 12 weeks (84 days) prior to the start of Period 1 study drug administration.
18. Has undergone whole blood collection of at least 800 mL in total within 52 weeks (364 days) prior to the start of Period 1 study drug administration.
19. Has undergone blood component collection within 2 weeks (14 days) prior to the start of Period 1 study drug administration.
20. Has any clinically relevant abnormality in vital signs or 12-lead electrocardiograms (ECG) at screening or on Day -1 of Period 1.
21. Has abnormal laboratory test values at screening or on Day -1 of Period 1 indicating clinically relevant underlying disease, or showing alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) >1.5×upper limit of normal (ULN).
22. Is unlikely to comply with the protocol requirements or is unsuitable as a participant of this study for any other reason in the opinion of the investigator or sub-investigator.

Takeda makes patient-level, de-identified data sets and associated documents available for all interventional studies after applicable marketing approvals and commercial availability have been received (or program is completely terminated), an opportunity for the primary publication of the research and final report development has been allowed, and other criteria have been met as set forth in Takeda's Data Sharing Policy (see www.TakedaClinicalTrials.com for details). To obtain access, researchers must submit a legitimate academic research proposal for adjudication by an independent review panel, who will review the scientific merit of the research and the requestor's qualifications and conflict of interest that can result in potential bias. Once approved, qualified researchers who sign a data sharing agreement are provided access to these data in a secure research environment.

Pharmacokinetic (PK) Analysis Set; PK analysis set included all treated participants who had no major protocol violations, completed the minimum element of the protocol, and had evaluable pharmacokinetic data.

Up to Day 25

At each visit the investigator had to document any occurrence of adverse events and abnormal laboratory findings. Any event spontaneously reported by the participant or observed by the investigator was recorded, irrespective of the relation to study treatment.