Patient description: A 3-day-old Asian female infant presents with jaundice that started a day ago. She was born at 38w3d of gestation, after an uncomplicated pregnancy. The family history is unremarkable. The baby is breastfed. Vital signs are reported as: axillary temperature: 36.3°C, heart rate: 154 beats/min, respiratory rate: 37 breaths/min, and blood pressure: 65/33 mm Hg. Her weight is 3.2 kg, length is 53 cm, and head circumference 36 cm. Her sclera are yellow and her body is icteric. No murmurs or any other abnormalities are detected in the heart and lung auscultation. Her liver and spleen are normal on palpation. Laboratory results are as follows: Serum total bilirubin: 21.02 mg/dL Direct bilirubin of 2.04 mg/dL AST: 37 U/L ALT: 20 U/L GGT: 745 U/L Alkaline phosphatase: 531 U/L Creatinine: 0.3 mg/dL Urea: 29 mg/dL Na: 147 mEq/L K: 4.5 mEq/L CRP: 3 mg/L Complete blood cell count within the normal range. She is diagnosed with uncomplicated neonatal jaundice that may require phototherapy.

Clinical trial eligibility criteria: eligible ages (years): 18.0-55.0,  Healthy Volunteers Healthy adult males and/or females (of non-childbearing potential), 18 to 55 years of age (inclusive) at the time of screening Body mass index ≥ 18.5 and ≤ 29.9 (kg/m2) and 55.0 and 100.0 kg (inclusive) for all cohorts Medically healthy without clinically significant (CS) abnormalities at the screening visit or Day -1, including: 1. Physical examination, vital signs including temperature, heart rate, respiratory rate, and blood pressure; 2. Triplicate electrocardiograms (ECGs) taken at least 1 minute apart with QT wave corrected for heart rate (HR) using Fridericia's method (QTcF) interval duration less than 450 msec obtained as an average from the triplicate screening and pre-dose Day 1 ECGs after at least 5 min in a semi-supine quiet rest; 3. Haemoglobin > 12.5, haematocrit 37%, white blood cell (WBC) count > 3.5, or platelet count equal to or greater than the lower limit of normal range of the reference laboratory (may be confirmed upon repeat analysis); 4. Creatinine, blood urea nitrogen (BUN), equal to or less than the upper limit of normal; alanine aminotransferase (ALT) and aspartate aminotransferase (AST) equal to or < 1.5 times the upper limit of normal for the reference laboratory and confirmed on repeat analysis; results of all other clinical chemistry and urine analytes without any CS abnormality. Discussion between the PI and the Sponsor Medical Monitor is encouraged regarding any abnormal laboratory value that is outside of the normal range during the pre-dose period Be non-smokers (including tobacco, e-cigarettes or marijuana) for at least 1 month prior to participation in the study Willing and able to provide written informed consent Be willing and able to comply with all study assessments and adhere to the protocol schedule Have suitable venous access for blood sampling If female, be of non-childbearing potential (e.g. post-menopausal as demonstrated by follicle stimulating hormone or surgical sterilization i.e., tubal ligation or hysterectomy). Provision of documentation is not required for female sterilization, verbal confirmation is adequate If male, a willingness not to donate sperm and if engaging in sexual intercourse with a female partner who could become pregnant, a willingness to use a condom in addition to having the female partner use a highly effective method of birth control (such as an intrauterine device, diaphragm, oral contraceptives, injectable progesterone, subdermal implants, or a tubal ligation). This criterion applies to males (and/or female partners) who are surgically sterile and must be followed from the time of first study drug administration until 30 days after the final administration of study drug  History or presence of significant cardiovascular, pulmonary, hepatic, renal, haematological, gastrointestinal, endocrine, immunologic, dermatologic or neurological disease, including any acute illness or surgery within the past 3 months determined by the PI to be clinically relevant History of known or suspected Clostridium difficile infection History of seizure disorders, except for a single febrile seizure in childhood Positive urine drug/alcohol testing at screening or Day -1 Positive testing for human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), or hepatitis C antibodies (HCV) History of substance abuse or alcohol abuse (defined as greater than 2 standard drinks on average each and every day, where 1 standard drink is defined as containing 10 g of alcohol and is equivalent to 1 can or stubby of mid-strength beer, 30 ml nip spirits, or 100 ml wine) within the previous 5 years Use of any prescription medication or any over-the-counter medication, including herbal products and vitamins within 7 days prior to randomization Documented hypersensitivity reaction or anaphylaxis to any medication Donation of blood or plasma within 30 days prior to randomization, or loss of whole blood of more than 500 mL within 30 days prior to randomization, or receipt of a blood transfusion within 1 year of study enrollment Participation in another investigational clinical trial within 30 days prior to Day 1