Drug-drug Interaction Study of CTP-543 and Rifampin in Healthy Adult Subjects

• CTP-543 (Drug): Rifampin as oral capsule

Primary outcomes

• AUC0-t [16 hours]: Area Under the Plasma Concentration-Time Profile
• AUC0-inf [16 hours]: Area Under the Plasma Concentration-Time Profile From Time Zero Extrapolated to Infinite Time
• Cmax [16 hours]: Maximum observed concentration of drug in plasma
• Tmax [16 hours]: Time to reach maximum observed concentration of drug in plasma

Secondary outcomes

• Number of Participants with Adverse Events (AEs) [Up to 47 days]: An adverse event is any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention

Sex: All, ages: 18 Years to 60 Years, accepts healthy volunteers

Inclusion Criteria:

* Non-smoker who has not used nicotine-containing products for at least 3 months prior to the first dosing and throughout the study
* Body mass index (BMI) ≥ 18.0 and ≤ 32.0 kg/m2 at Screening
* Medically healthy with no clinically significant medical history, physical examination, laboratory profiles, vital signs or ECGs
* If of reproductive age, willing and able to use a medically highly effective form of birth control 30 days prior to first dose, during the study and for 30 days following last dose of study medication
* Understands the study procedures in the informed consent form, and be willing and able to comply with the protocol

Exclusion Criteria:

* History or presence of clinically significant medical or psychiatric condition or disease
* History of any illness that might confound the results of the study or poses an additional risk to the subject by their participation in the study
* History or presence of alcohol or drug abuse within the past 2 years prior to the first dosing
* Females who are nursing, pregnant, or planning to become pregnant while in the study, and for 30 days after last dose of study drug
* Positive results at Screening for human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg) or hepatitis C virus (HCV)
* A positive test or history of incompletely treated or untreated tuberculosis
* Donation of > 499 mL of blood or plasma within 56 days of Screening (during a clinical trial or at a blood bank donation) and for 30 days after last dose of study drug