Recovery of Dysthyroid Optic Neuropathy in Glucocorticoid-Refractory Thyroid Eye Disease Patients Treated with Tocilizumab - 5441
My Session Status
Author’s Disclosure Block: Anne Xuan-Lan Nguyen, none; Stéphan Tobalem, none; Keith Perry, none; Steffie Arès, none; Francis Toupin, none; Matthieu Picard, none; Patrick Boulos, none; Evan Kalin-Hajdu, none; Isabelle Hardy, none
Abstract Body
Purpose: To assess the effects of IL-6 inhibitor Tocilizumab (TCZ) on the clinical course of refractory thyroid-eye disease (TED), including patients with dysthyroid optic neuropathy (DON). Study Design: Retrospective cohort study. Methods: This study was conducted on all TED patients treated with TCZ from 2021 to 2023 at University of Montreal Eye Center, Maisonneuve-Rosemont Hospital (Montreal, Canada). We included adult patients with active (clinical activity score/CAS ≥4/10 in the worst eye), moderate-to-severe and/or sight-threatening TED (EUGOGO guidelines) after failure of glucocorticoids (GCs). Primary outcomes were changes in CAS, thyroid-stimulating immunoglobulins (TSI), proptosis and diplopia. Secondary outcomes were changes in best corrected visual acuity (BCVA), visual fields, color vison, and pupillary reaction (RAPD). Data were collected at TCZ initiation, week 12, last dose, and last follow-up. We further examined disease recurrence at one-year post-study. Results: 16 patients (32 eyes) were recruited, including 9 patients (15 eyes) with DON. Of these 9, 5 had active DON refractory to GCs and 4 had residual DON from previous treatments.TCZ was administered subcutaneously with a median of 17.5 [IQR: 11-88] injections every week (n=10 patients), intravenously with a median of 4 [1-4] infusions monthly for 4 months (n=4), or both (n=2). Median duration of TCZ was 114 [77-1026] days.CAS improved at week 12 (mean reduction of 3.1 points) and last dose (-3.2 points) (p<0.001). CAS was ≤1 in 89% (week 12) and 93% (last dose) of patients. Reductions in TSI (-9.3 U/L) (p=0.002), proptosis (-0.9 mm) (p=0.025), and diplopia (5-fold risk reduction) (p=0.038) were noted at last dose.DON patients (n=9): CAS was ≤1 in 83% (week 12) and 87.5% (last dose) of patients; CAS reduction ≥2 in 100% at week 12. At last dose, improvements were noted for BCVA (-0.229 logMar) (p=0.028), color vision (+1.86 points (p=0.012), visual fields (-6.39 dB) (p<0.001) and RAPD (58-fold risk reduction) (p=0.005). One patient discontinued TCZ (adverse effects). Recurrence (CAS deterioration ≥2 points) occurred in 25% of patients (mean=236 days after last dose) during the 537-day follow-up.One year after the last follow-up, 2 out of the 16 patients were still treated with TCZ. All patients had inactive disease, with no new relapses. No adverse side-effects were objectified or reported post-treatment. Conclusions: TCZ effectively inactivated severe, refractory TED with a positive effect on DON. No DON patients required decompression surgery. IL-6 inhibitor should be investigated as a first-line agent in TED patients with DON.
