A Study of LY4268989 (MORF-057) in Healthy Participants

Inclusion Criteria: * Are healthy as determined by medical evaluation including medical history, physical examination, laboratory test, electrocardiograms (ECGs), and vital signs. * Cohort 5 includes Japanese participants. To qualify, the participants must be first-generation Japanese in the US, defined as the participant's biological parents, and all the participant's biological grandparents, being of exclusive Japanese descent, and being born in Japan. * Cohort 5 includes Chinese participants. To qualify as Chinese for this study, all 4 of the participant's biological grandparents must be of exclusive Chinese descent and born in China. * Have a body mass index within the range of 18.0 to 32.0 kilogram/square meter (kg/m²), inclusive, at screening. Exclusion Criteria: * Have a current or recent acute, active infection. For at least 30 days before screening and up to Day 1, participants must have no symptoms or signs of confirmed or suspected infection, and must have completed any appropriate anti-infective treatment. * Have presence of significant uncontrolled respiratory, cerebrocardiovascular, cardiovascular, hepatic, renal, gastrointestinal, endocrine, hematologic, neurologic or psychiatric disorders, or abnormal laboratory values at screening that, in the opinion of the sponsor or investigator, pose an unacceptable risk to the participant if participating in the study or of interfering with the interpretation of data. * Are immunocompromised to an extent that participation in the study would pose an unacceptable risk to the participant as determined by the investigator. * Use or intend to use prescription or nonprescription medication, including dietary supplements, vitamins, herbal supplements, traditional Chinese medicine, or alternative medicines, within 14 days or 5 half-lives (whichever is longer), prior to dosing, unless, in the opinion of the investigator and sponsor, the medication will not interfere with the study