The Efficacy and Safety of Tocilizumab in the Treatment of Refractory Ocular Myasthenia Gravis in Pediatric Patients.

INTRODUCTION/

Aims

Refractory pediatric ocular myasthenia gravis (OMG) remains difficult to manage. We evaluated tocilizumab's efficacy and safety in these patients.

Methods

In this single-center, retrospective analysis of prospectively collected registry data from Tangdu Hospital (China), pediatric refractory OMG patients received intravenous tocilizumab (8 mg/kg every 4 weeks) for 16 weeks as add-on therapy. Refractory disease required persistent symptoms despite adequate trials of ≥ 2 immunosuppressants, frequent relapses during glucocorticoid tapering, or intolerance of conventional oral immunosuppressants. The primary outcome was change in Myasthenia Gravis-Activities of Daily Living (MG-ADL) score from baseline to Weeks 4, 8, 12, and 16, analyzed using generalized estimating equations.

Results

All 10 patients (1 male, 9 females; median age 5.5 years, range 2-11) completed 16 weeks of follow-up. Seven (70%) were positive for antiacetylcholine receptor antibody (AChR-Ab). At Week 4, mean MG-ADL score decreased from 3.4 to 2.5 (incidence rate ratio[IRR], 0.74; 95% CI, 0.54-0.99; p = 0.048), with further reduction to 1.5 at week 16 (IRR, 0.44; 95% CI, 0.24-0.80; p = 0.007). Similarly, mean Quantitative MG (QMG) score dropped from 4.7 at baseline to 3.0 at Week 4 (IRR, 0.64; 95% CI, 0.41-0.99; p = 0.048) and further to 1.9 at Week 16 (IRR, 0.40; 95% CI, 0.24-0.69; p = 0.001). By Week 16, 50% of patients achieved minimal symptom expression, and 50% reduced prednisone requirements. Tocilizumab was well-tolerated with only one transient infusion-related dizziness.

Discussion

These preliminary findings suggest that tocilizumab may offer a safe and effective treatment option for children with refractory OMG.