The purpose of this study is to assess the relative bioavailability (BA) of 300 milligram (mg) TAK-935 tablets compared to 300 mg of TAK-935 solution and to determine the effect of food on the BA of TAK-935 300 mg tablets in healthy adult participants.

The drug being tested in this study is called TAK-935. The study will look at the relative BA of TAK-935 300 mg tablets compared to a TAK-935 300 mg oral solution and will assess the effect of food on the BA of TAK-935 300 mg tablets in healthy adult participants.

The study will enroll approximately 9 participants. Participants will be randomly assigned (by chance, like flipping a coin) to one of the 3 treatment sequences:

• TAK-935 (300 mg Tablets Fed + 300 mg Tablets Fasted + 300 mg Solution Fasted)
• TAK-935 (300 mg Tablets Fasted + 300 mg Solution Fasted + 300 mg Tablets Fed)
• TAK-935 (300 mg Solution Fasted + 300 mg Tablets Fed + 300 mg Tablets Fasted)

Administration of each dose will be separated by a washout period of at least 3 days. Participants will be asked to take single dose of TAK-935 tablet or oral solution on Day 1 of each Intervention Period.

This single center trial will be conducted in the United States. The overall time to participate in this study is 39 days. Participants will remain confined to the clinic from Day 1 of Intervention Period 1 to Day 3 of Intervention Period 3 and will be contacted by telephone 30 days after last dose of TAK-935 for a follow-up assessment.

Inclusion Criteria:

1. Weighs at least 45 kilogram (kg) and has a body mass index (BMI) from 18.0 to 30.0 kilogram per square meter (kg/m^2), inclusive at Screening and Day -2.

Exclusion Criteria:

1. Has received TAK-935 in a previous clinical study or as a therapeutic agent.
2. Has a history of any psychiatric disorder as diagnosed utilizing Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM 5) criteria.
3. Has any lifetime history of drug abuse (defined as any illicit drug use) or any lifetime history of alcohol abuse prior to the screening visit or is unwilling to agree to abstain from alcohol and drugs throughout the study. One unit is equivalent to a half-pint of beer or a single measure of spirits or 1 small glass of wine.
4. Has a history of cancer, except basal cell carcinoma which has been in remission for at least 5 years prior to Day 1.
5. Has a positive test result for hepatitis B surface antigen (HBsAg), hepatitis C virus (HCV) antibody, human immunodeficiency virus (HIV) antibody at Screening or a known history of human immunodeficiency virus infection.
6. Has used nicotine-containing products (including but not limited to cigarettes, pipes, cigars, chewing tobacco, nicotine patch or nicotine gum) within 28 days prior to Check-In Day -1. Cotinine test is positive at Screening or Check-In (Day -1).
7. Has poor peripheral venous access.
8. Has donated or lost 450 milliliter (mL) or more of his or her blood volume (including plasmapheresis), or had a transfusion of any blood product within 30 days prior to Day 1 of Period 1.

The safety analysis set included all participants who were enrolled and received study drug.

Treatment-emergent adverse events are adverse events that started after the first dose of study drug and no more than 30 days (Day 39) after the last dose of study drug

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.