Efficacy and safety of repository corticotropin injection for refractory cutaneous dermatomyositis: a prospective, open-label study

Cutaneous dermatomyositis (DM) is often refractory to multiple medications. Repository corticotropin injection (RCI) is FDA-approved for DM, but little is known about its efficacy and safety for treating cutaneous DM. We conducted a prospective, open-label trial assessing efficacy and safety of RCI for treating refractory cutaneous DM.DM patients with moderate-to-severe cutaneous activity [Cutaneous Dermatomyositis Disease Area and Severity Index activity (CDASI-A)] >14 despite prior treatment with ≥2 systemic agents were enrolled. Patients were initiated on 80 u RCI twice weekly for 6 months. Primary outcomes included significant decreases in CDASI-A and Physician's Global Assessment (PGA) scores at 6 months.Of nineteen patients enrolled, fifteen patients (11 females, 4 males) with DM (7 classic, 8 amyopathic) completed 6 months of RCI treatment. Patients were treated with a median 3.0 systemic medications prior to enrolment and were taking a median of 2.0 systemic medications at enrolment. Median baseline CDASI-A score was 19.0 and median PGA activity score was 2.5/10. For patient-reported outcomes, baseline median patient global skin score (PtGSS) was 3.0/10 and median dermatology life quality index (DLQI) score was 7.0/10. At 6 months, there were statistically significant improvements in CDASI-A scores (median= 10.0), PGA scores (median= 0.8/10), PtGSS scores (median= 7.0) and DLQI scores (median= 2.0), among others. Adverse effects were mild.RCI treatment resulted in statistically significant and clinically meaningful improvement in cutaneous DM activity and quality of life. Our results suggest RCI is an effective, safe, and well-tolerated treatment for patients with refractory cutaneous dermatomyositis.This clinical trial was registered with ClinicalTrials.gov (ClinicalTrials.gov Identifier: NCT01906372).