Inclusion Criteria:
* Healthy male subjects and female subjects of nonchildbearing potential, ages 18 to 55 years, inclusive, at the time of signing the ICF
* Sexually active men with a pregnant or a nonpregnant partner of childbearing potential must agree to use a double-barrier method of birth control, including a condom, and practice contraception during treatment and through 7 days post dose
* Capable of providing informed consent and following study requirements
Exclusion Criteria:
* Subjects who answer yes on the C-SSRS or, in the opinion of the investigator, present a serious risk of suicide
* Subjects with a current history of significant cardiovascular, pulmonary, gastrointestinal, renal, hepatic, metabolic, hematological, immunological, or neurological disease
* Subjects with a 12-lead ECG demonstrating either of the following (average of 3 ECGs obtained at the Screening Visit):
* QT interval corrected for heart rate using Fridericia's formula \>450 msec
* Left ventricular hypertrophy
* Orthostatic hypotension, which is defined as a decrease of ≥20 mmHg in systolic blood pressure and/or a decrease of ≥10 mmHg in diastolic blood pressure after at least 3 minutes of standing compared with the immediately previous supine/semi-recumbent blood pressure at Screening or at the prescan time point prior to baseline PET scan.
* Subjects with a current or past personal history of any psychiatric disorder as classified by DSM-5 criteria or immediate family members with any psychiatric disorder as classified by DSM-5 criteria that require treatment
* Subjects with a history of substance or alcohol-use disorder (DSM-5 criteria) within 2 years prior to signing the ICF
* Subjects with other abnormal laboratory test results, vital sign results, or ECG findings
* Subjects who currently use or have used tobacco or nicotine-containing products within 30 days prior to signing the ICF
* Subjects with history of prior radiation exposure for research purposes within the past year such that participation in this study would place them over FDA limits for annual radiation exposure (5 rem per year)
* Subjects with any anatomical abnormality in the head that would either preclude or tend to confound the analysis of study data, including any clinically significant abnormal findings from MRI of the head
* Current, past or anticipated exposure to radiation in the workplace
* Any subject with a significant acute illness within 7 days prior to administration of study drug or have had a major illness or hospitalization within 1 month prior to administration of study drug
* Any subject who, in the opinion of the sponsor, investigator, or medical monitor, should not participate in the trial
