The following is a summary of “Efficacy and Safety of Teprotumumab in Patients With Thyroid Eye Disease of Long Duration and Low Disease Activity,” published in the January 2024 issue of Endocrinology by Douglas, et al.

Thyroid eye disease (TED) can lead to chronic symptoms like proptosis, with early inflammatory stages potentially progressing to severe conditions. Teprotumumab, an insulin-like growth factor-1 receptor (IGF-1R) inhibitor, has previously shown efficacy in acute TED trials but has not been tested in chronic or low disease activity TED. For a study, researchers sought to assess the effectiveness and safety of teprotumumab in patients with longstanding/low inflammation TED through the first placebo-controlled trial in this population.

A randomized, double-masked, placebo-controlled trial was conducted across 11 US centers. Adults with TED duration of 2 to 10 years and low disease activity were enrolled. Patients received either intravenous teprotumumab or placebo every 3 weeks for 8 infusions. Proptosis improvement at Week 24 was the primary endpoint, with adverse events (AEs) also evaluated.

Of the 62 patients randomized, teprotumumab demonstrated a significantly greater improvement in proptosis at Week 24 (-2.41 [0.228]) compared to placebo (-0.92 [0.323]), with a difference of -1.48 (95% CI -2.28, -0.69; P = .0004). The incidence of AEs was similar between groups, with notable occurrences including hyperglycemia in 15% vs. 10% and hearing impairment in 22% vs. 10% with teprotumumab and placebo, respectively.

Teprotumumab significantly improved proptosis compared to placebo in patients with longstanding/low inflammation TED. The safety profile observed was consistent with previous findings, suggesting teprotumumab as a promising treatment option for this population.

Reference: academic.oup.com/jcem/article/109/1/25/7334391