The purpose of this study is to see if the study drug ABBV-154 is safe and able to treat subjects with moderately to severely active Crohn's Disease who have an inadequate response to or were intolerant of prior biologics. ABBV-154 is an antibody-drug conjugate, which means it is composed of an antibody (adalimumab) linked to another drug called a glucocorticoid receptor modulator (GRM). The adalimumab component helps to target and deliver the GRM into activated immune cells that are present in inflammation. The GRM component acts similarly to a steroid (such as prednisone) by reducing inflammation in the body but having less side effects than typically seen with steroids. Participation in this study could be up to approximately 77 weeks. Eligible participants may receive $100 for each completed study visit, for a total of $2800 if you complete all visits in Period 1: Induction and Period 3: Maintenance. If symptoms and the results from tests and examinations at Week 12 of the Induction Period require participation in Period 2: Re-Induction, participants will be paid $100 for each completed study visit, for a total of $600.

You may be eligible for this study if you meet the following criteria:

• Conditions: Crohn's Disease
• Age: 18 years - 75 years
• Gender: All