A Study to Evaluate Blood Levels of Bepirovirsen in Adult Participants With Severe or Moderate Kidney Disease

Prior treatment

• Current enrolment in another interventional study, or past participation in a study where an investigational medicine, vaccine or device was administered if, at the time of consent, it is within 5 half-lives or twice the duration of the biological effect (whichever is longer) of the product given in the previous study.
• Received any oligonucleotide or small interfering ribonucleic acid (siRNA) within the past 12 months.
• Exposure to more than 4 investigational products within the past 12 months.
• Current substance misuse or dependence, or a previous history of substance misuse or dependence that could interfere with ability to participate in the study.
  • Additional exclusion criteria for renal impairment groups (Group 1 and Group 2)
• Positive drug or alcohol screen (unless because of prescribed medication). Additional exclusion criterion for healthy control group (Group 3)
• Positive drug or alcohol screen.

Other illness

• Any medical condition that could affect the absorption, metabolism, or elimination of drugs, increase the risk of taking part in the study, or interfere with interpretation of the study data.
• History of vasculitis or any type of glomerulonephritis
• A positive blood test for hepatitis B, hepatitis C, or human immunodeficiency virus (HIV).
• History of renal transplantation or anticipated renal transplant during the study.

Lab values

• Urine albumin-to-creatinine ratio (uACR) \> 0.3 mg/mg (300 mg/g).

Other

• Use of creatine-containing supplements within 30 days of screening or intended use during the study.
• Average weekly alcohol intake of greater than 14 drinks for males or greater than 7 drinks for females.
• On dialysis or likely to require dialysis during the study.

• Age 18 to 80 years, inclusive
• Body weight greater than or equal to 50 kilograms (kg) and body mass index (BMI) within the range 19 to 40 kilograms per square meter (kg/m\^2).
• Males and females may participate. Female participants must not be pregnant or breastfeeding, and must be of non-childbearing potential, or agree to use a highly effective method of contraception.
• Capable of giving signed informed consent Additional inclusion criteria for renal impairment groups (Group 1 and Group 2)
• Severe renal impairment \[estimated glomerular filtration rate (eGFR) adjusted for actual body surface area (BSA) less than 30 milliliters per minute (ml/min); Group 1\] or moderate renal impairment \[eGFR adjusted for actual BSA between 30 and 59 ml/min; Group 2\], from any cause other than vasculitis or glomerulonephritis Additional inclusion criteria for healthy control participants with normal renal function (Group 3)
• Healthy, based on medical evaluation including medical history, physical examination, laboratory tests, and electrocardiogram (ECG).
• Normal renal function (eGFR adjusted for actual BSA greater than or equal to 90 ml/min)