Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of BBT-877 in Healthy Subjects

Inclusion Criteria:

• Healthy adult male and/or female (non-childbearing potential only), 19 to 55 years ofage, inclusive, at screening.

• Continuous non-smoker who has not used nicotine-containing products for at least 3months prior to the first dose and throughout the study.

• BMI ≥ 18.5 and ≤ 32.0 kg/m2 and weight ≥ 50 kg at screening.

• Medically healthy with no clinically significant medical history, physicalexamination, laboratory profiles, vital signs, as deemed by the PI or designee.

• No clinically significant history or presence of ECG findings as judged by the PI orqualified designee at screening and check-in.

• For a female, must be of non-childbearing potential and therefore must have undergoneone of the following sterilization procedures, at least 6 months prior to the firstdose:

1. hysteroscopic sterilization;

2. bilateral tubal ligation or bilateral salpingectomy;

3. hysterectomy;

4. bilateral oophorectomy; or be postmenopausal with amenorrhea for at least 1 yearprior to the first dose and follicle-stimulating hormone (FSH) serum levelsconsistent with postmenopausal status.

• A non-vasectomized, male subject must agree to use a condom with spermicide or abstainfrom sexual intercourse during the study until 90 days beyond the last dose of studydrug. (No restrictions are required for a vasectomized male provided his vasectomy hasbeen performed 4 months or more prior to the first dose of study drug. A male who hasbeen vasectomized less than 4 months prior to the first dose must follow the samerestrictions as a non-vasectomized male).

• If male, must agree to not donate sperm from the first dose until 90 days after thelast dose of study drug.

• Must have the ability to understand and sign a written informed consent form (ICF),which must be obtained prior to initiation of study procedures.

Exclusion Criteria:

• Subject is mentally or legally incapacitated or has significant emotional problems atthe time of the screening visit or expected during the conduct of the study.

• History or presence of clinically significant medical or psychiatric condition ordisease in the opinion of the PI or designee.

• History of any illness that, in the opinion of the PI or designee, might confound theresults of the study or poses an additional risk to the subject by their participationin the study.

• History or presence of alcoholism or drug abuse within the past 2 years prior to thefirst dose or regular alcohol consumption within 6 months prior to the first dose withan average weekly intake of greater than 21 glasses/units per week for males or 14glasses/units per week for females, with one unit = 150 mL of wine or 360 mL of beeror 45 mL of 45% alcohol.

• History or presence of hypersensitivity or idiosyncratic reaction to the study drug(s)or related compounds.

• History of anemia or history of decreased red blood cells (RBC).

• Estimated creatinine clearance <80 mL/min at screening.

• Liver function tests (serum ALT, AST, alkaline phosphatase) and serum bilirubin (totaland direct) > ULN.

• Baseline hemoglobin, hematocrit, RBC < lower limit of normal at screening and Day -1.

• Female subjects who are pregnant or who are lactating.

• Positive urine drug or alcohol results at screening or check-in.

• Positive urine cotinine at screening.

• Positive results at screening for human immunodeficiency virus (HIV), hepatitis Bsurface antigen (HBsAg), or hepatitis C antibodies (HCV).

• Unable to refrain from or anticipates the use of:

• Any drug, including prescription and non-prescription medications, herbalremedies, or vitamin supplements beginning approximately 14 days prior to thefirst dose and throughout the study. Hormone replacement therapy will not beallowed. After first dosing, acetaminophen (up to 2 g per 24 hours) may beadministered at the discretion of the PI or designee.

• Any drugs known to be significant inducers of CYP3A enzymes and/orP-glycoprotein, including St. John's Wort, for 28 days prior to the first dosingand throughout the study. Appropriate sources (e.g., Flockhart Table) will beconsulted to confirm lack of PK/PD interaction with study drug.

• Has been on a diet incompatible with the on-study diet, in the opinion of the PI ordesignee, within the 28 days prior to the first dose and throughout the study.

• Donation of blood or significant blood loss within 56 days prior to the first dose.

• Plasma donation within 7 days prior to the first dose.

• Exposure to more than four new chemical entities within 12 months prior to firstdosing day.

• The subject has participated in a clinical trial and has received an investigationalproduct within 30 days, or 5 half-lives of the investigational product (whichever islonger) of the first dose of study drug in the current study.

• Any condition or circumstance, in the opinion of the PI or designee, which may makethe subject unlikely to complete the study or comply with study procedures andrequirements, or may pose a risk to the subject's safety.