Orbital Volume Dynamics in Chronic, Low CAS Thyroid Eye Disease (TED): Imaging Evidence of Teprotumumab Treatment Response
Author: César Briceño
Base Hospital / Institution: Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA
ePoster presentation
Abstract ID: 25-277
Purpose
Teprotumumab has demonstrated efficacy in the treatment of both active and chronic thyroid eye disease (TED). Extraocular muscle (EOM) and orbital fat (OF) volumes have been shown to normalize toward control levels in active TED following teprotumumab treatment. This study compared orbital volumes in patients (pts) with chronic low CAS TED before and after teprotumumab with non-TED orbits.
Methods
This post hoc analysis included available data from a subset of teprotumumab pts from the Phase 4 trial (NCT04583735) with MRI pre-teprotumumab at baseline (n=16 female [F], 2 male [M] orbits) and/or post-teprotumumab at Wk24 (n=10 F, 4 M orbits). Pts had CAS ≤1, TED duration 2-10 years. EOM and OF volumes were measured bilaterally and compared to non-TED control orbits (100 orbits; 48 M, 52 F) using Welch’s t-tests. Due to sex differences, volumes were assessed in F and M+F using sex-matched controls.
Results
Mean (SD) EOM and OF volumes were larger in M vs F control orbits [EOM, 2774 (523) vs 2136 (441) mm3, respectively, p<0.001; OF, 11404 (2241) vs 9771 (1791) mm3, p<0.001]. Mean (SD) EOM and OF volumes of pre-treatment F TED orbits were significantly larger [EOM, 3296 (1743) mm3, p=0.018; OF, 15766 (3931) mm3, p<0.001] vs F controls. Post-teprotumumab treatment, there were no significant differences in EOM and OF volumes of F TED [EOM, 2470 (826) mm3, p=0.24; OF, 9055 (1852) mm3, p=0.28] vs controls. In the combined M+F group, mean (SD) OF volumes were significantly larger in pre-treatment TED orbits vs controls [15464 (3798) vs 10555 (2170), p<0.001]; EOM volumes were also larger [3170 (1680) vs 2442 (577), p=0.086]. Post-treatment, OF volumes in TED were significantly smaller [9031 (1728), p=0.007] while EOM volumes were similar [2261 (804), p=0.427] to controls. Sensitivity analysis in 6 pts with both pre-and post-treatment MRI showed similar results.
Conclusion
This data suggest that increased EOM and OF volumes noted in active TED persist in chronic TED and, despite longstanding disease and low CAS, can be returned to approximately normal non-TED control volumes with teprotumumab treatment.
Additional Authors
| First name | Last name | Base Hospital / Institution |
|---|---|---|
| Savvas | Nicolaou | Emergency and Trauma Imaging, Vancouver General Hospital, Vancouver, Canada |
| Lulu | Liu | Department of Radiology, University of British Columbia, Vancouver, Canada |
| Ada | Kumar | Amgen Inc., Thousand Oaks, CA, USA |
| Zhenxun | Wang | Amgen Inc., Thousand Oaks, CA, USA |
| Michael | Karon | Amgen Inc., Thousand Oaks, CA, USA |
| Galin | Spicer | Amgen Inc., Thousand Oaks, CA, USA |
| Shoaib | Ugradar | Private Practice, Beverly Hills, CA, USA |
