A Study to Investigate the Pharmacokinetics and Safety of Remibrutinib in Participants With Hepatic Impairment Compared With Matched Healthy Participants

Inclusion Criteria: All participants 1. Signed informed consent was obtained prior to participation in the study. 2. Male and non-childbearing potential female\* participants 18 to 70 years of age, inclusive, at Screening. 3. Women of non-childbearing potential were defined as women who were post menopausal or had surgical bilateral oophorectomy (with or without hysterectomy), total hysterectomy or bilateral tubal ligation at least 6 weeks prior to first dosing of study treatment. In the case of oophorectomy alone, only when the reproductive status of the woman was confirmed by follow-up hormone level assessment was she considered not of childbearing potential. Women were considered post-menopausal if they had 12 months of natural (spontaneous) amenorrhea with an appropriate clinical profile (e.g., age-appropriate history of vasomotor symptoms). 4. Must have been a non-smoker or a light smoker who smoked no more than 10 cigarettes (or equivalent) per day, at Screening. Smokers must have agreed to smoke no more than 5 cigarettes (or equivalent) per day from check-in until after Study Completion evaluations. 5. Must have been able to communicate well with the investigator and to understand and comply with the requirements of the study. Participants with mild, moderate, and severe HI (Groups 1, 2 and 3) 6. Must have weighed at least 50 kg to participate in the study and must have had a body mass index (BMI) within the range of 18.0 to 35.0 kg/m2, inclusive, at Screening. 7. Seated vital signs must have been within the following ranges at Screening and Baseline: * body temperature, 35.0 to 37.5°C, inclusive * systolic blood pressure (BP), 90 to 160 mmHg, inclusive * diastolic BP, 50 to 100 mmHg, inclusive * pulse rate, 50 to 110 bpm, inclusive 8. Had impaired hepatic function as defined by the Child-Pugh classification for severity of liver disease and had a Child-Pugh score in line with one of the following HI groups at Screening: * Group 1; mild (Class A); Child-Pugh score 5-6, inclusive * Group 2; moderate (Class B); Child-Pugh score 7-9, inclusive * Group 3; severe (Class C); Child-Pugh score 10-15, inclusive 9. Stable Child-Pugh status and no worsening of more than 1 point in Child-Pugh score within 28 days prior to first dosing of study treatment. 10. Participants with other stable medical disorders such as controlled diabetes, hyperlipidemia, hypothyroidism, etc., may have been eligible as long as they were considered appropriate for enrollment as determined by the investigator by past medical history, physical examination, ECG, and clinical laboratory tests at Screening. Healthy control participants (Group 4) 11. Each healthy participant must have matched the age (±10 years), body weight (±20%), and gender of at least one participant of Group 1 (Part 1), 2 (Part 1), or 3 (Part 2). 12. Must have weighed at least 50 kg to participate in the study and must have had a BMI within the range of 18.0 to 30.0 kg/m2, inclusive, at Screening. 13. Must have been in good health as determined by medical history, physical examination, ECG, and clinical laboratory tests at Screening. 14. Seated vital signs must have been within the following ranges at Screening and Baseline: * body temperature, 35.0 to 37.5°C, inclusive * systolic BP, 89 to 139 mmHg, inclusive * diastolic BP, 50 to 89 mmHg, inclusive * pulse rate, 45 to 90 bpm, inclusive Exclusion Criteria: All participants 1. Use of other investigational drugs within 5 half-lives or 30 days prior to first dosing of study treatment, whichever was longer. 2. History of hypersensitivity to the study treatment or its excipients or to drugs of similar chemical classes. 3. History or presence of malignancy of any organ system (other than treated localized basal cell or squamous cell carcinoma of the skin or in situ cervical cancer), treated or untreated, within the past 5 years of Screening, regardless of whether there was evidence of local recurrence or metastases. 4. History of immunodeficiency diseases or had a positive human immunodeficiency virus (HIV) test result at Screening. 5. History or presence of any ongoing, chronic, or recurrent infectious disease (including tuberculosis, atypical mycobacterioses, listeriosis, aspergillosis). 6. Female participants who were of childbearing potential, defined as all women physiologically capable of becoming pregnant. 7. Female participants who were pregnant or nursing (lactating). Pregnancy was defined as the state of a female participant after conception and until termination of gestation, confirmed by a positive human chorionic gonadotropin (hCG) laboratory test at Screening or Baseline. 8. Use of prohibited prescription or non-prescription medication or supplement. 9. Received any live vaccine within 8 weeks prior to first dosing of study treatment. 10. Received any coronavirus disease-2019 (COVID-19) vaccines within 2 weeks prior to first dosing of study treatment. 11. Clinical signs and symptoms consistent with COVID-19 (e.g., fever, dry cough, dyspnea, sore throat, fatigue) or confirmed infection by appropriate laboratory test within 2 weeks prior to Screening or tested positive during the Screening period before study site check in. 12. History or presence of significant bleeding risk or any coagulation disorder. 13. Donation or loss of 400 mL or more of blood within 8 weeks prior to first dosing of study treatment, or longer if required by local regulation. 14. Any surgical or medical condition which could have significantly altered the absorption, distribution, metabolism or excretion of drugs (apart from cholecystectomy), or which could have jeopardized the participants in case of participation in the study. 15. History of unhealthy alcohol use within 12 months prior to first dosing of study treatment, or evidence of such abuse as indicated by the laboratory assays (i.e., positive alcohol test) conducted during Screening or Baseline. Note: Participants who did not agree to comply with abstinence from alcohol use from 48 hours prior to first dosing of study treatment until after Study Completion evaluations were excluded. Unhealthy alcohol use was defined as a history of, or current alcohol misuse/abuse, defined as \> 21 drinks for males and \> 14 drinks for females in the same week. 16. Positive drug test at Screening or Baseline, unless the positive drug screen was due to prescription drug use that was approved by the investigator and Novartis. 17. Regular use of caffeine or methyl xanthine-containing products exceeding 800 mg (\~4 cups of coffee containing 200 mg caffeine per cup) per day. Participants with mild and moderate HI (Groups 1 and 2) 18. Abnormal clinical laboratory values for any of the following parameters at Screening or Baseline: * hemoglobin \< 9 g/dL * platelet count \< 30 × 109/L * white blood cell count \< 2.5 × 109/L * absolute neutrophil count \< 1.5 × 109/L * lymphocytes \< 0.8 × 109/L * total bilirubin (TBL) \> 8 mg/dL * serum amylase \> 2 × upper limit of normal (ULN) * INR \> 2.3 * serum ammonia level \> 200 μg/dL * corrected serum calcium \< 8.6 or \> 10.2 mg/dL 19. Severe complications of liver disease within the preceding 3 months of Screening. 20. Emergency room visit or hospitalization due to liver disease within the preceding 3 months of Screening. 21. Received liver transplant at any time in the past and/or was on immunosuppressant therapy at Screening. 22. Required paracentesis more than every 30 days for the management of ascites. 23. Transjugular intrahepatic portosystemic shunt and/or underwent portacaval shunting. 24. Acute hepatitis B virus (HBV) or acute hepatitis C virus (HCV) infection. A positive hepatitis B surface antigen (HBsAg) test excluded a participant. Participants with a positive HCV antibody test had HCV ribonucleic acid (RNA) levels measured. Participants with positive (detectable) HCV RNA were excluded. 25. Clinically significant abnormal findings in physical examination, ECG or clinical laboratory evaluations, not consistent with known liver disease. Participants having had myocardial infarction \< 5 years of Screening were not eligible to participate; participants having had myocardial infarction ≥ 5 years of Screening could have been eligible to participate. 26. Presence of moderate to severe impaired renal function as indicated by any of the following at Screening: * Estimated glomerular filtration rate (eGFR) \< 45 mL/min/1.73 m2 based on the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation * Serum creatinine \> 1.5 × ULN 27. Encephalopathy Grade 3 or worse within 28 days of planned first dosing of study treatment. 28. Primary biliary cholangitis or biliary obstruction. 29. History of gastrointestinal (GI) bleeding within the past 3 months prior to Screening. 30. Clinically significant illness within 2 weeks prior to first dosing that could have jeopardized safety of the study participant and/or altered the study results as judged by the investigator. Participants with severe HI (Group 3) 31. Abnormal clinical laboratory values for any of the following parameters at Screening or Baseline: * hemoglobin \< 8.5 g/dL * platelet count \< 30 × 109/L * white blood cell count \< 2.5 × 109/L * TBL \> 8 mg/dL * serum amylase \> 2 × ULN * serum ammonia level \> 200 μg/dL * INR \> 2.3 32. Severe complications of liver disease within the preceding 3 months of Screening. 33. Emergency room visit or hospitalization due to liver disease within the preceding 1 month of Screening. 34. Received liver transplant at any time in the past and/or was on immunosuppressant therapy at Screening. 35. Required paracentesis more than every 30 days for the management of ascites. 36. Transjugular intrahepatic portosystemic shunt and/or have undergone portacaval shunting. 37. Acute HBV or acute HCV infection. A positive HBsAg test excluded a participant. Participants with a positive HCV antibody test had HCV RNA levels measured. Participants with positive (detectable) HCV RNA were excluded. 38. Clinically significant abnormal findings in physical examination, ECG or clinical laboratory evaluations, not consistent with known liver disease. Participants having had myocardial infarction \< 5 years of Screening were not eligible to participate, participants having had myocardial infarction ≥ 5 years of Screening could have been eligible to participate. 39. Presence of moderate to severe impaired renal function as indicated by any of the following at Screening: * eGFR \< 45 mL/min/1.73 m2 based on the CKD-EPI equation * Serum creatinine \> 1.5 × ULN 40. Encephalopathy Grade 3 or worse within 28 days of planned first dosing of study treatment. 41. Primary biliary cholangitis or biliary obstruction. 42. History of GI bleeding within the past 3 months prior to Screening. 43. Documented presence of esophageal varices (Stage 3 or 4) based on the evaluation of the participant's medical history at Screening and Baseline. 44. History, clinical evidence or suspicion of a hepato-cellular carcinoma (HCC) based on sonographical and/or laboratory results (i.e., α-fetoprotein \[AFP\] \> 12 IU/mL \[2 × ULN\] at Screening). 45. Severe ascites and/or pleural effusion. 46. Participants with clinical evidence of suspected acute liver failure as judged by the investigator. 47. Clinically significant illness within 2 weeks prior to first dosing that could have jeopardized safety of the study participant and/or altered the study results as judged by the investigator. Healthy control participants (Group 4) 48. Significant illness which had not resolved within 2 weeks prior to first dosing of study treatment. 49. Liver disease or liver injury as indicated by abnormal liver function tests at Screening. Any single parameter of alanine aminotransferase (ALT), AST, gamma-glutamyltransferase (GGT), or alkaline phosphatase (ALP) exceeding 1.2 × ULN or ≥ 1.5 × ULN TBL OR any elevation above ULN of more than one parameter of ALT, AST, GGT, ALP or TBL. 50. Known to have Gilbert's syndrome. 51. Positive result for HBsAg or HCV antibody at Screening. 52. Hemoglobin levels below 11.0 g/dL for males and 10.0 g/dL for females at Screening or Baseline. 53. History or presence of impaired renal function as indicated by clinically significantly abnormal creatinine or blood urea nitrogen (BUN) and/or urea values, or abnormal urinary constituents at Screening. In the case where a safety laboratory assessment at Screening or Baseline was outside of the range specified above, the assessment may have been repeated once at Screening and/or once at Baseline. If the repeat value remained outside of the specified ranges, the participant was excluded from the study.