Post Hoc Analysis of Predictors of Clinical Response to Repository Corticotropin Injection in Persistently Active Rheumatoid Arthritis

Introduction A phase IV clinical trial confirmed the safety and efficacy of repository corticotropin injection (RCI, Acthar ® Gel) in patients with refractory rheumatoid arthritis (RA) that was nonresponsive to standard-of-care therapies. The objective of this post hoc analysis was to identify baseline demographics and clinical characteristics that may be predictors of response to RCI. Methods The phase IV trial was a two-part, randomized, placebo-controlled withdrawal study. Post hoc analysis was conducted with the open-label portion of the trial data, in which all 258 subjects received RCI (80 U) twice weekly for 12 weeks. Responders were subjects who achieved low disease activity (LDA) by a Disease Activity Score with 28-joint count and erythrocyte sedimentation rate (DAS28-ESR) of