Tocilizumab for the Management of Thyroid-Associated Orbitopathy

Purpose: To describe the efficacy of tocilizumab in the treatment of a cohort of patients with active thyroid-associated orbitopathy. Methods: Patients were identified with active thyroid-associated orbitopathy who were intolerant of or had progression of disease despite systemic corticosteroids and subsequently were treated with tocilizumab between January 2015 and December 2020. Clinical Activity Score, Thyroid-Associated Ophthalmopathy Scale score, and thyroid-stimulating immunoglobulin levels were assessed prior to initiation of tocilizumab, following the first dose, and after the completion of treatment. Results: Eleven patients were candidates for and underwent treatment with tocilizumab, 9 of which met criteria for analysis. Average age was 55.6 years. Average time between onset of active thyroid-associated orbitopathy and completion of tocilizumab was 6.5 months. Average number of infusions was 4.2. There was a statistically significant reduction in Clinical Activity Score, Thyroid-Associated Ophthalmopathy Scale score, and thyroid-stimulating immunoglobulin levels when comparing pre-treatment values (mean Clinical Activity Score 6.78 +/- 1.09, mean Thyroid-Associated Ophthalmopathy Scale score 10.2 +/- 1.92, mean thyroid-stimulating immunoglobulin level 440.6 [%]) to values immediately following completion of treatment (mean Clinical Activity Score 0.44 +/- 0.53, mean difference 6.3 points, p < 0.001 [95% CI, 5.5-7.2]; mean Thyroid-Associated Ophthalmopathy Scale score 1.2 +/- 1.09, mean difference 9.0 points, p < 0.001 [95% CI, 7.2-10.8]; mean thyroid-stimulating immunoglobulin level 200.7 [%], mean difference 239.9 [%], p = 0.001 [95% CI, 124.3-355.4]). One patient had elevation of cholesterol following therapy induction. Patients were followed for an average of 23.6 months after treatment. No patients had recurrence of active disease after completion of tocilizumab. Conclusions: This study supports the use of tocilizumab as a therapy for the inflammatory phase of thyroid-associated orbitopathy.