A Study of Effects of Selpercatinib in Hepatically Impaired Participants and Healthy Participants

Inclusion Criteria: * Female participants of non-childbearing potential who are agreeable to take birth control measures until study completion * Males who are capable of fathering a child must agree to use one of the following methods of contraception from the time of the dose administration through 6 months after dose administration: * Male sterilization, with documented confirmation of surgical success. Male subjects will be surgically sterile for at least 90 days prior to Check-in (Day -1). If documentation is not available, male subjects must follow one of the contraception methods below: * Male condom with spermicide, or * For a female partner of male study participant: * Intrauterine device (IUD) (hormonal IUD; eg, Mirena®). Copper IUDs are acceptable (eg, ParaGard®); * Established use of oral, implanted, transdermal, or hormonal method of contraception associated with inhibition of ovulation; or * Bilateral tubal ligation. * Body mass index (BMI) ≥ 18.0 and ≤ 32.0 kilograms per meter squared (kg/m²) and had a minimum weight of at least 50 kg at screening * Have normal blood pressure, pulse rate, electrocardiogram (ECG), and blood and urine laboratory test results that are acceptable for the study Exclusion Criteria: * Are currently participating in or completed a clinical trial within the last 30 days or any other type of medical research judged to be incompatible with this study * Have previously participated or withdrawn from this study * Have or use…