Majority of proptosis responders maintain long-term response with teprotumumab

Results from a study to assess long-term proptosis response and diplopia grade in patients treated with teprotumumab (Tepezza, Horizon) for thyroid eye disease (TED), demonstrated that the majority of teprotumumab-treated patients maintained improvements 51 weeks after the last dose, similar to the phase 2 study, according to an on-demand video presentation at 2020 AAO Virtual.

Teprotumumab, a fully human monoclonal antibody inhibitor of insulin-like growth factor-1 receptor (IGF-1R), is indicated for the treatment of TED, a progressive and vision-threatening rare autoimmune disease.

For the OPTIC study, patients were followed for 48 weeks after the 24-week study (final infusion at Week 21) for maintenance of response off treatment to Week 72. Results at Week 24 showed that 83% (34/41) of patients had a ≥2 mm proptosis reduction and 68% (19/28) had a ≥1 grade diplopia improvement (16/28 with score of 0) in the teprotumumab arm. Of these 24-week responders, 56% (19/34) maintained proptosis response, while 58% (11/19) maintained ≥1 grade diplopia improvement and 50% (8/16) maintained a diplopia score of 0 at Week 72. There were no new safety concerns in the OPTIC follow-up period.

OPTIC-X data provide evidence supporting the use of teprotumumab in patients who have had TED for a longer period of time than what was originally studied in the phase 2 and phase 3 clinical trials (up to 16 months vs an average of 6 months in OPTIC). The OPTIC-X extension trial will continue to evaluate treatment response.

Reference
Douglas RS, et al. Long-term assessment of proptosis and diplopia from the OPTIC trial of teprotumumab in thyroid eye disease. Presented at: AAO 2020 Virtual [Session: PA038.01]