Short and Long Term Effects of Teprotumumab on Diplopia and Strabismus Associated with Thyroid Eye Disease

Teprotumumab has been shown to be effective in reducing inflammation and proptosis in patients with thyroid eye disease. This study focused on the short and long-term effects of teprotumumab on diplopia and strabismus. Twenty patients were followed after receiving teprotumumab, on average, 2 years post-treatment, with a range of 1 to 5 years. Detailed sensorimotor exams including prism and alternate cover test were performed. All patients but one had a decrease in proptosis, ranging from 1 to 10 mm, with an average of 3.4 mm. Fifteen patients had diplopia in primary position pre-treatment. Forty six percent had a clinically significant improvement in diplopia when treatment was initially finished. This decreased to 33% after 10 to 18 months post treatment due to diplopia symptoms returning. Three patients whose diplopia did not improve with treatment initially, relapsed (had an increase in TED symptoms). The patients in this study remained stable after 18 months up to 5 years post-treatment. It is advisable to follow patients with active disease regularly for diplopia changes up to 18 months post-treatment.