About this trial
The purpose of this study is to evaluate how well LY4213663 is tolerated and what side effects may occur in healthy participants and participants with rheumatoid arthritis (RA). The study drug will be administered either subcutaneously (SC) (under the skin) or intravenously (IV) (into a vein in the arm).
Blood tests will be performed to investigate how the body processes the study drug and how the study drug affects the body. The study will last approximately 33 weeks excluding screening.
Eligibility criteria
Qualifiers
Have a body mass index (BMI) of 18.0 to 32.0 kilogram per square meter (kg/m²), inclusive
Have a body weight at least 50 kilograms and BMI within the range 18.0 to 40.0 kg/m² (inclusive) at screening
Have a diagnosis of adult-onset RA for at least 3 months prior to screening
Disqualifiers
Have a history or presence of cardiovascular, respiratory, hepatic, ophthalmological, renal, gastrointestinal, endocrine, hematological, neurological, or psychiatric disorders capable of significantly altering the absorption, metabolism, or elimination of drugs
Have Class 4 RA according to American College of Rheumatology (ACR) revised criteria
Have a 12-lead electrocardiogram (ECG) abnormality at screening
Have a current or recent acute active infection
Trial design
Treatments tested in this trial
- LY4213663
- LY4213663
- Placebo
- Placebo