Tepezza Hearing Loss Lawsuit Lawsuit Tracker

Thyroid eye disease (TED), also called Graves' ophthalmopathy, is an autoimmune condition that causes the muscles and fatty tissue behind the eyes to swell, leading to eye bulging (proptosis), double vision, pain, and in severe cases vision loss. TED affects an estimated 16,000 Americans per year and is closely associated with Graves' disease, an overactive thyroid condition. Before Tepezza, treatment options were limited to steroids, orbital radiation, and surgery. Teprotumumab, sold under the brand name Tepezza, is a monoclonal antibody that works by blocking insulin-like growth factor 1 receptor (IGF-1R). The FDA granted Tepezza Breakthrough Therapy designation and approved it in January 2020, making it the first and only FDA-approved medication specifically for TED. It is administered as a series of eight intravenous infusions over approximately 21 weeks. Horizon Therapeutics, a Dublin-based pharmaceutical company, developed and marketed Tepezza. In December 2023, Amgen completed its acquisition of Horizon Therapeutics for $27.8 billion, assuming responsibility for the Tepezza product line and its associated liabilities. At roughly $300,000 per treatment course, Tepezza is one of the most expensive drugs in the United States. The hearing damage mechanism centers on the role of IGF-1R in the inner ear. IGF-1R is expressed in cochlear hair cells, where it supports cell survival, prevents programmed cell death, and promotes the regeneration of cochlear synapses. By blocking IGF-1R throughout the body — not just in the eye orbit — Tepezza may deprive inner ear hair cells of critical survival signaling, leading to sensorineural hearing loss, tinnitus, autophony, and eustachian tube dysfunction. Clinical trial data submitted to the FDA showed hearing impairment in 10% of Tepezza patients compared to 0% on placebo, but these rates were based on limited study populations. A 2021 Endocrine Society prospective study found that 65% of patients experienced audiometric changes after treatment. The FDA required label changes in July 2023 acknowledging that hearing loss from Tepezza may be severe and permanent. The MDL was formed in June 2023 and assigned to Judge Thomas M. Durkin in the Northern District of Illinois. The first lawsuit was filed in 2022. As of early 2026, 273 cases are pending with 282 total filed. Active litigation continues.