Study to Evaluate the Pharmacokinetics of Lemborexant (E2006) and Its Metabolites in Subjects With Normal Renal Function or With Severe Renal Impairment

Inclusion Criteria

Inclusion Criteria for All Participants:

• Male or female participants, ages 18 to 79 years, inclusive, at the time of informed consent.
• Body Mass Index between 18 and 40 kilograms per meters squared (kg/m^2), inclusive, at Screening.
• Voluntary agreement to provide written informed consent, and the willingness and ability to comply with all aspects of the protocol.
• Nonsmokers or smokers who smoke 20 cigarettes or less per day.
• Participants with normal liver function.

Additional Inclusion Criteria for Healthy Participants:

• Estimated glomerular filtration rate (eGFR) is ≥ 90 mL/min/1.73 m^2, as determined by the Modification of Diet in Renal Disease (MDRD) formula.

Additional Inclusion Criteria for Participants with Renal Impairment:

• Diagnosis of severe renal impairment (eGFR is 15 to 29 mL/min/1.73 m^2, as determined by the MDRD formula) that has been stable (without any change in disease status) for 60 days prior to study Screening and is confirmed on Day -1, as determined by the investigator by MDRD formula. If the renal function classification for the participant changed from screening to Day -1, eGFR should be repeated once within 24 to 48 hours. If eGFR variability across these scheduled and repeat time points indicates the participant does not consistently meet the criteria for one renal category group, participant enrollment into a renal category group will be at the discretion of the medical monitor and investigator, in consultation with the Sponsor.

Exclusion Criteria

Exclusion Criteria for All Participants:

• Females who are breastfeeding or pregnant at Screening or Baseline.
• Females of childbearing potential who did not use a highly effective method of contraception within 28 days before study entry, or who did not agree to use an approved method of contraception from 28 days before study entry, throughout the entire study period, and for 28 days after study drug discontinuation.
• Intake of food supplements (including herbal preparations), foods or beverages that may affect cytochrome P450 (CYP) 3A4 (CYP3A4) enzyme (e.g., alcohol, grapefruit, grapefruit juice, grapefruit-containing beverages, apple or orange juice, vegetables from the mustard green family [e.g., kale, broccoli, watercress, collard greens, kohlrabi, Brussels sprouts, mustard] and charbroiled meats) within 2 weeks before dosing until study discharge.
• Use of an herbal preparation containing Saint John's Wort within 4 weeks before dosing until study discharge.
• Known to be positive for human immunodeficiency virus.
• Presence of acute and active liver disease, or acute liver injury, as indicated by (1) an abnormal liver function test, or (2) clinical or laboratory signs of acute, active viral hepatitis (including B and C as demonstrated by positive serology at Screening). Participants with stable, chronic, inactive viral hepatitis B or C may be enrolled based on investigator's opinion.
• Corrected QT interval for heart rate on electrocardiograms (ECGs) by Fridericia's formula (QTcF) >480 milliseconds (msec) at Screening or Day -1. Before excluding a participant with QTcF >480 msec at Screening, ECG should be repeated once to confirm.
• A known or suspected history of drug or alcohol abuse disorder within 6 months prior to Screening.
• A positive urine drug test or a positive breathalyzer alcohol test at Screening or Day -1.
• Participation in another interventional clinical trial within 4 weeks, or 5 times the half-life of the investigational drug (whichever is longer), of lemborexant administration.
• Engaged in heavy/strenuous physical exercise within 2 weeks prior to check-in on Day -1 (e.g., marathon runners, weight lifters).
• Unwilling to abide by the study requirements, or in the opinion of the investigator, is not likely to complete the study.
• History of clinically significant drug or food allergies, or is presently experiencing significant seasonal allergies.
• Recent weight change that is consid