Eligibility Details:  
        Inclusion Criteria:
          -  Men and women aged 18 through 55 years, inclusive.
          -  Body mass index within the range 18.5 to 32.0 kg/m2 (inclusive).
          -  Healthy subjects as determined by medical history, physical examination including
             neurological examination, vital signs, electrocardiogram (ECG), and clinical
             laboratory tests.
          -  Negative tests for hepatitis B surface antigen, hepatitis C virus antibodies and human
             immunodeficiency virus (HIV-1 or HIV-2) antibody, and syphilis at screening.
          -  Nonsmokers or ex-smokers and agrees not to use nicotine containing products from
             screening through 48 hours after final discharge from the Clinical Trial Unit.
          -  Negative screen for alcohol and drugs of abuse at screening and admission.
          -  Women must not be of childbearing potential by reason of surgery or at least 1 year
             postmenopausal (i.e., 12 months without menstrual period), or menopause confirmed with
             an estradiol level of <30 pg/mL and follicle-stimulating hormone level of >40 IU/L at
             screening.
          -  Men must be infertile, or truly abstinent of heterosexual intercourse, or heterosexual
             partner is not of childbearing potential, or must agree to use an effective method of
             contraception throughout the study and for 28 days after last dose of study drug. Men
             must agree to not provide sperm donation during that same period.
          -  Able and willing to be available for the duration of the study.
          -  Willing and able to give written informed consent to participate.
          -  Able to understand and comply with protocol instructions.
          -  Agree not to receive any vaccination within 21 days prior to admission and through Day
             7 after final discharge from the Clinical Trial Unit.
          -  Agrees not to use nonprescription drugs, including vitamins, antacids, and herbal and
             dietary supplements within 14 days or 5 drug elimination half-lives, whichever is
             longer.
        Exclusion Criteria:
        - Subjects with significant previous or ongoing disease or disorder, including for example:
        cardiovascular diseases; hypertension; cancer or neoplasia; diabetes; hepatic, endocrine,
        metabolic, respiratory, renal, gastrointestinal (except appendectomy), hematological or
        Axis I or II psychiatric disorders.
          -  Clinical laboratory test results outside the normal range at screening that are
             considered clinically significant by the Investigator.
          -  Clinically significant, in the opinion of the Investigator, infection or inflammation
             at time of screening or admission.
          -  Acute gastrointestinal symptoms at time of screening or admission or a clinical
             diagnosis of irritable bowel syndrome (IBS) per ROME IV criteria.
          -  Average QTcF interval recorded on screening and pre-dose ECG must be not more than 450
             msec.
          -  Any current or previous illicit use of Class A drugs such as opiates, cocaine,
             ecstasy, lysergic acid diethylamide (LSD), and amphetamines (Class B).
          -  An alcoholic intake greater than 14 units per week or unwillingness to stop alcohol
             consumption for the duration of the study.
          -  Use of any investigational medication within 3 months prior to the start of this study
             or scheduled to receive an investigational drug during the course of this study, or
             for 30 days or five half-lives, whichever is longer, following the last dose of study
             medication.
          -  History of severe allergies or multiple adverse drug reactions, including penicillin
             and cephalosporins.
          -  Any condition which compromises their ability to give informed consent or to
             communicate with the Investigator as required for the completion of this study.