Intervention: Grazoprevir
Trial phase: Phase 1
ATC code: J05AP11 | J05AP54
SMILES: C=C[C@@H]1C[C@]1(NC(=O)[C@@H]1C[C@@H]2CN1C(=O)[C@H](C(C)(C)C)NC(=O)O[C@@H]1C[C@H]1CCCCCc1nc3ccc(OC)cc3nc1O2)C(=O)NS(=O)(=O)C1CC1
Sex: All
Age groups: Adult | Older Adult
Healthy volunteers: Accepts Healthy Volunteers
Participants at risk: 8
Group description: Participants with severe HI received 50 mg of Grazoprevir once a day for 10 consecutive days during Part 3 of the study.
Eligibility criteria:
Inclusion Criteria:

If female, must be of non-childbearing potential or willing to use at least 2 acceptable methods of contraception from enrollment to 2 weeks after the last dose of study drug
No clinically significant abnormality on electrocardiogram

Hepatic Insufficiency Participants Only:

Other than hepatic insufficiency with features of cirrhosis, is otherwise in good health based on medical history, physical examination, vital signs, and laboratory safety tests
Chronic (>6 months), stable (no acute episodes of illness within the previous 2 months due to deterioration in hepatic function) hepatic insufficiency with features of cirrhosis due to any etiology
Score on the Child-Pugh scale must range from 5 to 6 (mild hepatic insufficiency) to from 7 to 9 (moderate hepatic insufficiency) to from 10 to 15 (severe hepatic insufficiency)

Matched Healthy Participants Only:

- In good health based on medical history, physical examination, vital signs, and laboratory safety tests

Exclusion Criteria:

History of any illness that might confound the results of the study or poses an additional risk to the participant
History of clinically significant endocrine, gastrointestinal (other than related to their hepatic impairment), cardiovascular, hematological, immunological, renal, respiratory, or genitourinary abnormalities or diseases
Pregnancy
Estimated creatinine clearance of ≤60 mL/min
History of stroke, chronic seizures, or major neurological disorder
History of neoplastic disease (including leukemia, lymphoma, malignant melanoma), or myeloproliferative disease, regardless of the time since treatment
Unable to refrain from or anticipates the use of any medication, including prescription and non-prescription drugs or herbal remedies (such as St. John's Wort, green tea, gingko, coenzyme Q, ginseng, echinacea, etc.) or nutritional supplements (e.g., garlic supplements), beginning approximately 2 weeks (or 5 half-lives) prior to administration of the initial dose of study drug, throughout the study, until the poststudy visit
Participated in another investigational study within 4 weeks
History of significant multiple and/or severe allergies or has had an anaphylactic reaction or significant intolerability to prescription or non-prescription drugs or food

Hepatic Insufficiency Participants Only:

- Has a history of hepatitis C infection by serology, regardless of most recent viral load status.

Matched Healthy Participants Only:

History of any chronic and/or active hepatic disease including elevations of serum transaminases, hepatitis, biliary tract disease, or a history of any significant gastrointestinal surgery.
History of hepatitis C. Participants with a history of self-limited hepatitis A with complete resolution documented at least 6 months prior to entry will be eligible for inclusion