Teprotumumab for thyroid eye disease in patients with hypothyroid/euthyroid state: a multicenter case series

Teprotumumab, a novel IGF-1R antibody was recently shown to significantly reduce the signs of acute and chronic thyroid eye disease (TED) related to hyperthyroidism. Given the lower incidence of TED associated with hypothyroidism / euthyroidism, there is a paucity of data regarding the efficacy of teprotumumab in this group.

In this multicenter study, consecutive patients who had been diagnosed with TED, presenting with either hypothyroidism or euthyroidism as their baseline thyroid dysfunction and treated with teprotumumab were included. All patients had measurements of proptosis, clinical activity scores (CAS), diplopia scores and four-point strabismus scores before and after therapy.

Twenty-six patients met the inclusion criteria. Mean age was 48 ± 14 years old and mean duration of TED prior to treatment was 31 ± 43 months. All patients received 8 infusions. Mean (SD) reduction in proptosis for study orbits was 2.7 mm (1.8) (p < 0.05) and 1.8 mm (2.0) for the fellow orbit (p < 0.05). In the study orbit, mean (SD) CAS was 2.3 (1.3) before therapy and 1.0 (1.0) following therapy (p < 0.05). At baseline, mean (SD) diplopia score was 1.2 (1.1) and 0.9 (1.1) following therapy (p < 0.05).

Teprotumumab reduces proptosis and inflammation in patients presenting with TED associated with hypothyroidism and euthyroidism. The results of this study highlight the potential for teprotumumab therapy in this subgroup and also provide a unique insight into the potential role of the IGF-1R in these patients.