['schizophrenia']
['tak-058', 'ondansetron', 'tak-058 placebo', 'ondansetron placebo']

        Inclusion Criteria:

          1. 18 to 60 years of healthy and schizophrenic participants, inclusive, at the time of
             informed consent.

          2. Has acceptable clinical laboratory evaluations (including clinical chemistry,
             hematology and complete urinalysis).

          3. Meets schizophrenia criteria as defined by the Diagnostic & Statistical Manual of
             Mental Disorders, 5th Edition (DSM-V).

          4. Are on a stable dose of single second-generation antipsychotics (SGA) for at least 2
             months prior to Screening as documented by medical history and assessed by site staff.

          5. Demonstrates Positive and Negative Syndrome Scale (PANSS) total score of less than
             equal to (<=) 85.

          6. Has a P50 ratio of > 0.5 at both screening assessments.

        Exclusion Criteria:

          1. Has a history in the last year or currently receiving treatment with clozapine or
             olanzapine.

          2. Has taken any excluded medications, supplements or food products.

          3. Has a history of gastrointestinal disease that would influence the absorption of study
             drug or have a significant medical history of any disease that would contraindicate
             the administration of TAK-058, ondansetron, or a similar compound.

          4. Has substance abuse or dependence within previous 12 months, unstable mood or anxiety
             disorder.

          5. Has a current diagnosis of a significant psychiatric illness other than schizophrenia
             per DSM-V and is in an acute phase/episode.

          6. Has clinically meaningful hearing loss per investigator's judgment.
      