Objective:

Assess disease outcomes and changes in corticosteroid use in patients with gMG receiving C5ITs.

Background:

Corticosteroids are commonly used for chronic management of gMG but associated with adverse effects. Furthermore, guidelines recommend steroid-sparing agents when corticosteroids alone are ineffective/contraindicated/intolerable. C5ITs eculizumab and ravulizumab are approved gMG treatments that employ targeted inhibition of terminal complement activation to reduce neuromuscular junction damage. We describe steroid utilization patterns and associated outcomes in C5IT-treated gMG patients to determine whether steroid sparing is achievable with C5IT use.

Design/Methods:

Retrospective analysis of the IQVIA PharMetrics® Plus claims database (1/1/2006-6/30/2022) examined patients ≥18 years with ≥2 claims (≥30 days apart) with MG diagnosis ICD9 or ICD10 codes filed via non-ophthalmologic specialist as primary, continuous enrollment from 6months before first C5IT claim, and continuous C5IT treatment (with gap ≤90 days) during 18-month follow-up. Outcomes included prednisone average daily dose (ADD), gMG crises and exacerbations.

Results:

Among 140 identified patients with gMG (commercial insurance, 73%; Medicare, 27%), 46% were male, mean (95% CI) age was 52.7 (49.9-55.6) years at first MG claim, with additional 2.9 (2.6-3.3) years until C5IT initiation. 66 patients received prednisone at some point between C5IT initiation through follow-up. During 6 months prior to C5IT initiation, 50% (33/66) of patients received high-dose prednisone (ADD >10 mg/day) which decreased to 35% (23/66) after 12-months of C5IT, accompanied by a 40% decrease in prednisone ADD (16.4 to 9.9 mg/d; P<0.01). During 6-months of C5IT treatment, exacerbations were reduced by 76% (107.1 to 25.7 per 100 patient-years; P<0.01) and crises by 67% (42.8 to 14.3 per 100 patient-years; P<0.01), with reductions maintained through 12-18 months (each, 12.8 per 100 patient-years).

Conclusions:

These medical claims data showed statistically significant reductions in prednisone ADD after 12-months’ C5IT and gMG exacerbations and crises during 6 months of C5IT treatment compared with 6 months before C5IT initiation.