Tocilizumab use for optic nerve compression in thyroid eye disease: a prospective longitudinal cohort.

PURPOSE: To assess the effectiveness of tocilizumab in reverting the signs and symptoms of dysthyroid optic neuropathy (DON) in thyroid eye disease and the need for emergency orbital decompression. The secondary outcomes are to identify the optimal number of tocilizumab cycles to achieve the primary outcome, to analyze the association between thyroid stimulating immunoglobulin (TSI), clinical activity score (CAS) and proptosis in response to the treatment and the need for rehabilitative orbital decompression.

METHODS: Prospective longitudinal cohort study that included 13 patients who had unilateral or bilateral dysthyroid optic neuropathy (DON) due to severe and progressive sight-threatening thyroid eye disease based on the CAS system. Patients were seen in this facility starting from July 2017, and all had received intravenous tocilizumab.

RESULTS: Initial visual acuity mean was 0.52 ± 0.38 and the final were 0.93 ± 0.11 with a mean difference of 0.41 and P < 0.00245. The mean CAS prior to the initiation of the treatment was 7.92 ± 0.66 and the final was 2.85 ± 1.03 with mean difference of 5.07 and P < 0.00001. Initial mean proptosis was 24.85 ± 2.31 and the final was 21.78 ± 2.18 with a mean difference of 3.07 and P < 0.000497. No emergency orbital decompression was performed. TSI was high initially in all cases with a wide range of 2.4 to 40 IU/L and with a mean of 10.70 ± 13.40. The final TSI mean was 2.90 ± 3.90 with a mean difference of 7.81 and significant P value (P < 0.0272).

CONCLUSION: Tocilizumab use in optic nerve compression showed promising results as it can be the primary or an alternative treatment option.