Hearing Dysfunction after Treatment with Teprotumumab for Thyroid Eye Disease

circle PURPOSE: To characterize the frequency, severity, and resolution of hearing dysfunction in patients treated with teprotumumab for thyroid eye disease (TED). circle DESIGN: Prospective observational case series. circle METHODS: Ophthalmic examination and adverse event assessment, including otologic symptoms, were performed at baseline, after infusions 2, 4, and 8, and at 6-month follow-up in consecutive patients who received at least 4 teprotumumab infusions. Laboratory test results were collected at baseline and during treatment. Audiometry, patulous eustachian tube (PET) testing, and otolaryn-gology evaluation were obtained for patients with new or worsening otologic symptoms, with a subset obtaining baseline and posttreatment testing. circle RESULTS: Twenty-seven patients were analyzed (24 females, 3 males, average 56.3 years old). Twentytwo patients (81.5%) developed new subjective oto-logic symptoms, after a mean of 3.8 infusions (SD 1.8). At 39.2-week average follow-up after the last infusion, most patients with tinnitus (100%), ear plugging/fullness (90.9%), and autophony (83.3%) experienced symptom resolution, whereas only 45.5% (5 of 11) of patients with subjective hearing loss/decreased word comprehen-sion experienced resolution. Six patients underwent base-line and posttreatment audiometry, 5 of whom devel-oped teprotumumab-related sensorineural hearing loss (SNHL) and 1 patient also developed PET. Three of the 5 patients with teprotumumab-related SNHL had persis-tent subjective hearing loss at last follow-up. A prior his-tory of hearing loss was discovered as a risk factor for teprotumumab-related SNHL (P =.008). circle CONCLUSIONS: Hearing loss is a concerning adverse event of teprotumumab, and its mechanism and re-versibility should be further studied. Until risk factors for hearing loss are better understood, we recommend base-line audiometry with PET testing and repeat testing if new otologic symptoms develop. Screening, monitoring, and prevention guidelines are needed.