A Study to Assess the Safety, Tolerability and Pharmacokinetics of Multiple Subcutaneous Injections of ABBV-257 in Subjects With Rheumatoid Arthritis

This is a Phase 1, randomized, double-blind, placebo-controlled, multiple dose study designed to assess the safety, tolerability, pharmacokinetics, and immunogenicity of different dose levels of ABBV-257 given with methotrexate. ABBV-257 or placebo will be administered once every other week (EOW) for a total of 4 doses. Subjects will continue on their stable dose of methotrexate weekly throughout participation in the study. This study will be conducted in approximately 24 subjects in 3 dose groups, with 8 subjects per group. Within each group, 6 subjects will be randomized to receive ABBV-257 and 2 subjects will receive placebo. Subjects participating in one dose group will be ineligible to participate in another dose group in the study.