Repository Corticotropin Injection (Acthar(®) Gel) for Refractory Severe Noninfectious Keratitis: Efficacy and Safety from a Phase 4, Multicenter, Open-Label Study

INTRODUCTION: Noninfectious keratitis is a painful corneal inflammation treated with topical cyclosporine and other immunosuppressants. Additional treatment options are needed for keratitis that does not improve with standard therapies. Repository corticotropin injection (RCI; Acthar(®) Gel) is approved to treat severe acute and chronic allergic and inflammatory processes involving the eye and its adnexa, including keratitis. This phase 4, multicenter, open-label study assessed the efficacy and safety of RCI for refractory severe noninfectious keratitis. METHODS: Patients were ≥ 18 years old with persistent severe keratitis despite treatment with topical immunosuppressants. Patients received 80 U of RCI subcutaneously twice weekly for 12 weeks followed by a 4-week taper. Assessments included all domains of the Impact of Dry Eye on Everyday Life (IDEEL) Questionnaire, Ocular Discomfort and 4-Symptom Questionnaire, and Visual Analog Scale (VAS). Corneal fluorescein and conjunctival lissamine green staining, Conjunctival Redness Scale, tear production (Schirmer’s test), visual acuity, slit lamp examination, and intraocular pressure were also assessed. Safety was evaluated via treatment-emergent adverse events. Analyses were performed using the modified intent-to-treat (mITT) population (patients who received ≥ 1 dose of RCI and contributed any post-baseline efficacy data). RESULTS: In the mITT population (N = 35), 50.0% (95% confidence interval, 33.2% to 66.8%) of patients experienced clinically important improvements in the symptom bother domain of the IDEEL Questionnaire at week 12 of RCI therapy. All domains of the IDEEL and the Ocular Discomfort and 4-Symptom Questionnaire showed improvements at week 12 of RCI treatment. The most pronounced improvements in the VAS at week 12 were for eye dryness and eye discomfort. Corneal staining, conjunctival staining, conjunctival redness, and tear production showed early improvements that were sustained through week 12. No new safety signals for RCI were identified. CONCLUSIONS: RCI is safe and effective for refractory severe noninfectious keratitis that has not improved with other approved therapies. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT04169061. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40123-021-00400-y.