The purpose of this study is to evaluate the pharmacokinetics (PK) and safety of VX-121/tezacaftor/deutivacaftor (VX-121/TEZ/D-IVA) in participants with moderate hepatic impairment and in matched healthy participants.

This clinical trial information was submitted voluntarily under the applicable law and, therefore, certain submission deadlines may not apply. (That is, clinical trial information for this applicable clinical trial was submitted under section 402(j)(4)(A) of the Public Health Service Act and 42 CFR 11.60 and is not subject to the deadlines established by sections 402(j)(2) and (3) of the Public Health Service Act or 42 CFR 11.24 and 11.44.).

Key Inclusion Criteria:

• Cohort 1: Participants with Moderate Hepatic Impairment

  • Participants will satisfy the criteria for moderate hepatic impairment defined as a Child-Pugh total score of 7 to 9 points at the screening visit
  • Participants will have chronic (≥6 months) documented liver disease

• Cohort 2: Matched Healthy Participants

  • Participants will be matched during screening to participants with hepatic impairment for cigarette smoking habit, age, sex, and weight

Key Exclusion Criteria:

• Cohort 1: Participants with Moderate Hepatic Impairment

  • History of febrile illness or other acute illness
  • History of solid organ or bone marrow transplantation
  • History or presence of severe hepatic encephalopathy (Grade >2)
  • Any condition possibly affecting drug absorption
  • Severe portal hypertension
  • Significant renal dysfunction (creatinine clearance <50 milliliter per minute [mL/min] ) estimated according to the method of Cockcroft and Gault at the screening Visit or Day-1

• Cohort 2: Matched Healthy Participants

  • History of febrile illness or other acute illness
  • Any condition possibly affecting drug absorption

Other protocol defined Inclusion/Exclusion criteria may apply.

Details on Vertex data sharing criteria and process for requesting access can be found at: https://www.vrtx.com/independent-research/clinical-trial-data-sharing