The main purposes of this study are: 1. To learn more about the safety and side effects of different formulations of LY3375880 and 2. To measure how much LY3375880 gets into the blood stream and how long it takes to get out of the body. The study will last about 85 days. Screening may occur up to 28 days prior to enrollment.

Inclusion Criteria:

• Are overtly healthy males or females, as determined by medical history and physical examination
• Have a body mass index of 18.0 to 32.0 kilograms per meter squared (kg/m²) inclusive
• Females who are not of child-bearing potential
• Males who agree to use a reliable method of birth control during the study and for 120 days following the final administration of LY3375880
• Are reliable and willing to make themselves available for the duration of the study and are willing to follow study procedures

Exclusion Criteria:

• Have known allergies to LY3375880, related compounds or any components of the formulation, or history of significant atopy
• Have participated or are currently enrolled in clinical trials with LY3375880
• Have infections or evidence of infections
• Are pregnant, lactating or breast feeding