Surgical Timing for Patients with Thyroid Eye Disease Treated with Teprotumumab: A Collaborative Multicenter Study.

Purpose: To compare regression rates, characteristics, and surgical outcomes of thyroid eye disease patients who underwent orbit, strabismus, or eyelid surgery at various times during or after teprotumumab treatment.

Design: Multicenter, retrospective, observational cohort study.

Participants: Adult patients (age >18) with a minimum of 4 infusions of teprotumumab treatment for thyroid eye disease who had had eye surgery during or after treatment.

Methods: Two groups were formed based on surgery timing: group 1 (G1) (<180 days since last infusion) and group 2 (G2) (≥180 days since last infusion).

Main outcome measures: The primary outcome was postoperative regression rates. Secondary outcomes were postoperative regression characteristics, regression treatment, and orbital decompression proptosis reduction.

Results: This study evaluated 53 patients (81% female) who underwent 78 surgeries. G1 comprised 24 individuals with 34 surgeries, while G2 comprised 29 patients with 44 surgeries. Regression rates did not significantly differ between G1 and G2 (20.8% vs. 14.7%, p = 0.611). Compared with G1 patients, patients in G2 who regressed showed a significant mean increase in Clinical Activity Score (4.2 vs. 6.1, p = 0.027) and a nonsignificant yet measured increase in proptosis when compared with those in G1 (2.9 vs. 4.25, p = 0.298) at the time of regression. Compared with G1 patients, G2 patients who regressed were equally likely to undergo a repeat course of teprotumumab as group 1 (p = 0.14) but underwent a higher number of additional surgical procedures (p = 0.057). Thyroid stimulating immunoglobin levels uptrended more often in patients who regressed.

Conclusion: Our study suggests that while the rate of regression may not differ significantly, the severity, clinical impact, and need for additional surgery might be more pronounced for patients who have surgery more than 6 months after their last teprotumumab dose.