A Single-Dose Study of the Pharmacokinetics of MK-4618 in Patients With Hepatic Insufficiency (MK-4618-013)

This study is planned to be conducted in two parts. Part 1 of the study will include
participants with moderate hepatic insufficiency and healthy participants. If Part 2 is
conducted, Part 2 of the study will include participants with mild hepatic insufficiency.

Inclusion Criteria

For both healthy participants and participants with hepatic insufficiency:

- Continuous non-smokers who haven't used nicotine-containing products for at least 3
months prior to study drug administration

- Body mass index (BMI) ≤39 kg/m^2

- Good health based on medical history, physical examination, vital signs, laboratory
safety tests, and electrocardiogram (ECG)

- Females of childbearing potential must be sexually inactive for 14 days prior to
study drug administration and throughout study or use acceptable birth control method

- Females of non-childbearing potential must have undergone an acceptable sterilization
procedure at least 6 months prior to Day 1 of study or be postmenopausal with
amenorrhea for at least 1 year prior to Day 1

- Non-vasectomized males must agree to use a condom with spermicide or abstain from
sexual intercourse during the trial and for 3 months after study drug administration

For participants with hepatic insufficiency only:

- Diagnosis of chronic, stable, hepatic insufficiency

- For Part 1 Participants: Child-Pugh scale range from 7 to 9

- For Part 2 Participants: Child-Pugh scale range from 5 to 6

Exclusion Criteria

- History or presence of significant cardiovascular, pulmonary, renal, hematologic,
gastrointestinal, endocrine, immunologic, dermatologic, neurological disease

- History or presence of alcoholism or drug abuse within the past 2 years

- Females who are pregnant or lactating

- Use of any drugs or substances known to be significant inhibitors or inducers of
cytochrome P3A (CYP3A) enzymes and/or permeability glycoprotein (P-gp)