A Study to Learn If the Study Medicine Called Carbamazepine Changes How the Body Processes the Other Study Medicine Ibuzatrelvir in Healthy Adults

Inclusion criteria

Participants are eligible to be included in the study only if all of the following criteria apply:

-Male participants and female participants who are not of childbearing potential who are overtly healthy as determined by medical evaluation including medical history, physical examination, laboratory tests, blood pressure, pulse rate and standard 12 lead ECG

Exclusion criteria

Participants are excluded from the study if any of the following criteria apply:

• Evidence or history of clinically significant hematological, renal, endocrine, pulmonary, gastrointestinal, cardiovascular, hepatic, psychiatric, neurological, or allergic disease (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at the time of dosing).
• Any medical or psychiatric condition including recent (within the past year) or active suicidal ideation/behavior or laboratory abnormality or other conditions that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study.
• Subjects shown to carry or be positive for HLA-B*1502 or HLA-A*3101 (genotyping alleles/markers related to carbamazepine-associated hypersensitivity reactions, including SJS/TEN).
• Screening supine BP ≥140 mm Hg (systolic) or ≥90 mm Hg (diastolic) for participants <60 years; and ≥150/90 mm/Hg for participants ≥60 years old, following at least 5 minutes of supine rest. If systolic BP is ≥ 140 or 150 mm Hg (based on age) or diastolic ≥90 mm Hg, the BP should be repeated 2 more times and the average of the 3 BP values should be used to determine the participant's eligibility.
• An eGFR <60 mL/min/1.73m², as determined by the CKD-EPI equation using Screat calculated using the recommended formulas
• Standard 12-lead ECG that demonstrates clinically relevant abnormalities that may affect participant safety or interpretation of study results (eg, QTcF >450 ms, complete LBBB, signs of an acute or indeterminate- age myocardial infarction, ST-T interval changes suggestive of myocardial ischemia, second- or third- degree AV block, or serious bradyarrhythmias or tachyarrhythmias). If QTcF exceeds 450 ms, or QRS exceeds 120 ms, the ECG should be repeated twice and the average of the 3 QTcF or QRS values used to determine the participant's eligibility. Computer-interpreted ECGs should be overread by a physician experienced in reading ECGs before excluding a participant.
• Participants with ANY of the following abnormalities in clinical laboratory tests at screening and prior to dosing in each period, as assessed by the study-specific laboratory and confirmed by a single repeat test, if deemed necessary: ALT, AST, Bilirubin ≥1.5 x ULN. Participants with an elevated total bilirubin consistent with Gilberts Disease may have a direct bilirubin measured and would be eligible for this study provided the direct bilirubin level is ≤ ULN.