The purpose of this study is to determine in healthy participants the percentage of LY4064809 that enters bloodstream after oral administration. Blood tests will be performed to investigate how the body processes the study drug. For each participant, the study will last about 21 days, not including screening. Participants will remain in the clinical research center for 14 days.

Inclusion Criteria:

• Must be healthy as shown by medical history, physical examination, laboratory tests and heart monitoring
• Must have normal blood pressure and pulse rate
• Must have a history of a minimum of 1 bowel movement per day
• Must have body mass index (BMI) between 18 and 32 kilograms per square meter (kg/m2)
• Must be healthy men or healthy women who are not of childbearing potential
• Healthy men with partners who can become pregnant must remain abstinent or use contraceptives consistent with local regulations

Exclusion Criteria:

• Must not have a significant history or presence of metabolic disease, heart, liver, gallbladder, bile ducts, digestive, blood or nervous system disorders that could affect the way the body absorbs and processes the study drug
• Must not have an abnormal electrocardiogram (ECG)
• Must not have a history of major surgery within 30 days of entering study
• Must not have a history of cancer within 5 years of screening
• Must not have known allergies to LY4064809 or related compounds
• Must not have history of multiple or severe drug reactions or allergies which required treatment with steroids or epinephrine
• Must not have history or presence of psychiatric conditions that would prevent the participant from following study instructions.
• Must not use medications, except acetaminophen within 14 days of the first dose of LY4064809 and during the clinic stay
• Must not have participated in and been dosed in more than 2 radiolabeled drug studies in the last 12 months
• Must not have had exposure to significant diagnostic, therapeutic or employment-related radiation within 12 months
• Must not have participated in any other radiolabeled investigational study drug trial within 6 months prior to admission.
• Must not show evidence of human immunodeficiency Virus (HIV) infection or positive HIV-1 and HIV-2 antibodies
• Must not have evidence of Hepatitis C virus (HCV) infection or a positive HCV antibody test.
• Must not have evidence of Hepatitis B virus (HBV) infection or a positive Hepatitis B surface antigen (HBsAg)
• Must not have alcohol intake deemed significant by the investigator
• Must not use tobacco, smoking-cessation products, e-cigarettes (nicotine and non-nicotine), or nicotine products within 90 days prior to LY4064809 administration and discharge from the clinical research unit (CRU) or early termination (ET)