A Study of MK-8189 in Participants With Bipolar I Disorder (MK-8189-020)
The goal of this study is to evaluate the safety and tolerability of MK-8189 in participants with stable bipolar I disorder. There will be no hypothesis testing in this study.
- EligibilityCriteria: Inclusion Criteria:  The main inclusion criteria include but are not limited to the following:  Meets diagnostic criteria for bipolar I disorder, manic or mixed features according to the Diagnostic and statistical manual of Mental Disorders TR (DSM-5 TR) and considered to be in a non-acute phase of their illness. History of receiving and tolerating antipsychotic medication within the usual dose range employed for bipolar I disorder. Body mass index is 18 and 40 kg/m^2, inclusive. If currently taking an antipsychotic, is able to discontinue it's use at least 5 days prior to study start and the duration of the study.  Exclusion Criteria:  The main exclusion criteria include but are not limited to the following:  Untreated or uncompensated endocrine, gastrointestinal, cardiovascular, hematological, hepatic, immunological, renal, respiratory, genitourinary, or major neurological abnormalities or diseases. Evidence or history of a primary DSM-5 axis I psychiatric diagnosis other than those specified for inclusion. History of cancer (malignancy). Evidence or history of mental retardation, borderline personality disorder, or organic brain syndrome. History of neuroleptic malignant syndrome or moderate to severe tardive dyskinesia. Substance-induced psychotic disorder or behavioral disturbance. DSM-5 TR defined substance use disorder within 3 months of screening. History of seizure disorder beyond childhood or is receiving treatment with any anticonvulsant to prevent seizures. Positive test(s) for hepatitis B surface antigen, hepatitis C antibodies or human immunodeficiency virus. Major surgery or donation/loss of 1 unit of blood within 4 weeks prior to screening. Received any vaccine starting from 30 days prior to study intervention or is scheduled to receive any vaccine through 30 days following study intervention. - HealthyVolunteers: No - Gender: All - MinimumAge: 18 Years - MaximumAge: 60 Years - StdAgeList: Adult