Repository Corticotropin Injection, IVMP Deliver Similar Results for Optic Neuritis

Repository corticotropin injection (RCI) and intravenous methylprednisolone (IVMP) treatments for acute optic neuritis (ON) have no clinically meaningful between-group differences, according to research published in the Journal of Neuro-Ophthalmology.

Investigators conducted a multicenter, prospective, randomized clinical trial of adult patients with acute ON (<2 weeks duration) treated with either repository corticotropin injection or IVMP (ClinicalTrials.gov Identifier: NCT01838174). 

They used serial optical coherence tomography (OCT) to evaluate peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell plus inner plexiform layer thickness (GC+IPL). The primary outcome was the difference in the mean pRNFL thickness in the affected eye at 6 months minus the mean pRNFL thickness in the contralateral eye at baseline adjusted for the baseline mean pRNFL thickness of the contralateral eye. 

The study enrolled 37 patients (median age, 34.2 years; 73% women), 19 who received repository corticotropin injection and 18 who received IVMP treatment. The mean time from symptom onset to treatment was 8.8 days. 

The investigators found no difference in the primary outcome, loss of average pRNFL thickness in the affected eye at 6 months, between the repository corticotropin injection and IVMP groups (mean, -13.1 vs -11.7 µm, respectively; P =.88).

For additional outcomes, they found no difference between the RCI and IVMP groups in 6-month attenuation of GC+IPL thickness (-13.8 vs -12.0 µm; P =.58) and frequency of pRNFL swelling at 1 month (63% vs 72%; P =.73) and 3 months (26% vs 31%; P =.99). The study revealed similar improvements in visual function and patient-reported outcomes in both treatment groups but no significant difference between the groups.

Adverse events were reported in 71% of patients who received repository corticotropin injection and 61% of patients received IVMP. No serious adverse events were reported.

“The outcomes derived from 2 different, albeit effective interventions for acute ON serves to support the construct validity of using a commonly occurring and eloquent inflammatory demyelinating syndrome,” the researchers report.

Limitations of the study included discontinuation of the study prior to reaching the planned enrollment, likely making it underpowered to detecting small differences in the OCT outcomes, and inclusion of patients with prior ON in the contralateral eye.

Disclosure: This research was supported by Mallinckrodt Pharmaceuticals. Please see the original reference for a full list of disclosures.