Change in lacrimal gland volume and aqueous tear production following treatment with teprotumumab.

Background: Dry eye syndrome occurs in up to 85% of patients with thyroid eye disease (TED). Lacrimal gland enlargement correlates with subjective tearing and a reduction in quality of life in patients with TED.

Methods: In this prospective longitudinal study, patients presenting for the treatment of TED were considered for eligible. Primary outcomes included a change in the volume of the lacrimal gland and the production of tears following treatment with teprotumumab. The volume of lacrimal glands and proptosis was calculated using 3D volumetric analysis. Tear production was measured by Schirmer's test and associated symptoms were assessed using the VLSQ-8. The orbit with the most proptosis was designated the study orbit and the contralateral orbit was designated the fellow orbit.

Results: Twenty patients were included. Mean (SD) age was 61 (18) and mean duration of TED prior to therapy was 48 months (47). Lacrimal gland volume in the study orbit decreased from 768 mm (288) to 486 mm (173) (p < 0.01) following therapy. For the fellow orbit, volume reduced from 637 mm (261) to 379 mm (147) (p < 0.01). Schirmer's test reading (STR) in the study orbit increased from 14.5 mm (8.2) to 23 mm (10) (p < 0.01) (59%) following treatment. In the fellow orbit, STR increased from 12.7 mm (7) to 21 mm (9) post therapy (69%) (p < 0.01). There was a significant improvement on all parts of the VLSQ-8.

Conclusion: Teprotumumab significantly reduces TED related expansion of the lacrimal gland, increases tear production, and improves dry eye symptoms.