Eligibility Details:  
        Inclusion Criteria:
          1. Healthy, adult, male or female (of non childbearing potential only) 19 55 years of
             age, inclusive, at screening.
          2. Continuous non smoker who has not used nicotine containing products for at least 3
             months prior to (the first) dosing and throughout the study, based on subject self
             reporting.
          3. Body mass index (BMI) ≥ 18 and ≤ 32.0 kg/m2 at screening.
          4. Medically healthy with no clinically significant medical history, physical
             examination, neurological examination, ophthalmic examination, laboratory profiles,
             vital signs or ECGs, as deemed by the PI or designee.
          5. A female subject must be of non childbearing potential and must have undergone one of
             the following sterilization procedures at least 6 months prior to (the first) dosing:
               -  hysteroscopic sterilization;
               -  bilateral tubal ligation or bilateral salpingectomy;
               -  hysterectomy;
               -  bilateral oophorectomy; or
               -  be postmenopausal with amenorrhea for at least 1 year prior to (the first) dosing
                  and follicle stimulating hormone (FSH) serum levels consistent with
                  postmenopausal status.
          6. A non vasectomized, male subject must agree to use a condom with spermicide or abstain
             from sexual intercourse during the study until 90 days after (the last) dosing. (No
             restrictions are required for a vasectomized male provided his vasectomy has been
             performed 4 months or more prior to (the first) dosing of study drug. A male who has
             been vasectomized less than 4 months prior to study (first) dosing must follow the
             same restrictions as a non vasectomized male).
          7. If male, must agree not to donate sperm from the first dosing until 90 days after (the
             last) dosing.
          8. Able to swallow multiple capsules.
          9. Understands the study procedures in the informed consent form (ICF), and be willing
             and able to comply with the protocol.
        Exclusion Criteria:
          -  1. Is mentally or legally incapacitated or has significant emotional problems at the
             time of the screening visit or expected during the conduct of the study.
             2. History or presence of clinically significant medical or psychiatric condition or
             disease in the opinion of the PI or designee.
             3. History of any illness that, in the opinion of the PI or designee, might confound
             the results of the study or poses an additional risk to the subject by their
             participation in the study.
             4. Is at suicidal risk in the opinion of the PI as per the following criteria:
               1. Any suicide attempts within 12 months prior to screening or any suicidal intent,
                  including a plan, within 3 months prior to screening.
               2. C-SSRS answer of "YES" on suicidal ideation within 3 months prior to screening.
                  5. History or presence of alcoholism or drug abuse within the past 2 years prior
                  to (the first) dosing.
                  6. History or presence of hypersensitivity or idiosyncratic reaction to the study
                  drug or related compounds.
                  7. History of allergy to lignocaine/fluorescein (LF) or tropicamide (T) (eye
                  examination agents).
                  8. History of seizures (childhood febrile seizures are excepted). 9. Female
                  subjects of childbearing potential. 10. Female subjects with a positive pregnancy
                  test or who are lactating. 11. Positive urine drug or alcohol results at
                  screening or check in. 12. Positive results at screening for human
                  immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), or hepatitis C
                  virus (HCV).
                  13. Supine blood pressure is less than 90/40 mmHg or greater than 140/90 mmHg at
                  screening.
                  14. Supine heart rate is lower than 40 bpm or higher than 99 bpm at screening.
                  15. Estimated creatinine clearance <90 mL/min at screening. 16. Unable to refrain
                  from or anticipates the use of any drug including prescription and non
                  prescription medications, herbal remedies, or vitamin supplements beginning 14
                  days prior to the first dosing and throughout the study. Drugs known to be
                  significant inducers of cytochrome P450 (CYP) enzymes and/or P-glycoprotein (P
                  gp), including St. John's Wort will be prohibited for 28 days prior to the first
                  dosing and throughout the study. After dosing, acetaminophen (up to 2 g per 24
                  hours) may be administered at the discretion of the PI or designee. For subjects
                  having CSF sampling, topical medication for minor dermatological conditions,
                  stool softeners, local anesthetics, and/or intravenous normal saline may be
                  permitted as appropriate for lumbar puncture procedure for CSF sample collection
                  at the discretion of the PI.
                  17. Has been on a diet incompatible with the on study diet, in the opinion of the
                  PI or designee, within the 30 days prior to (the first) dosing and throughout the
                  study.
                  18. Donation of blood or significant blood loss within 56 days prior to (the
                  first) dosing.
                  19. Plasma donation within 7 days prior to (the first) dosing. 20. Participation
                  in another clinical study within 30 days prior to the (first) dosing. The 30 day
                  window will be derived from the date of the last blood collection or dosing,
                  whichever is later, in the previous study to Day 1 (of Period 1 for the Fed
                  Cohort) of the current study.
                  21. History or presence of: risk factors for Torsade de Pointes (e.g., heart
                  failure, cardiomyopathy, or family history of Long QT Syndrome); sick sinus
                  syndrome, second or third degree atrioventricular block, myocardial infarction,
                  pulmonary congestion, symptomatic or significant cardiac arrhythmia, prolonged
                  QTcF interval, or conduction abnormalities.
                  22. Has an abnormal screening ECG indicating a second- or third- degree AV block,
                  or one or more of the following: QRS > 120 msec, QTcF > 450 msec for males and >
                  460 msec for females, PR interval > 220 msec. Any rhythm other than normal sinus
                  rhythm, which is interpreted by the PI or designee to be clinically significant
                  at screening or check-in.