Tepezza Hearing Loss Lawsuit - Amgen Faces MDL 3079 Over Drug's Alleged Permanent Damage

Hundreds of patients who received Tepezza infusions for thyroid eye disease have filed lawsuits alleging the drug caused permanent hearing damage - including hearing loss, tinnitus, and muffled hearing - that persisted long after treatment ended. The cases are consolidated in a federal multidistrict litigation in Chicago, and drug maker Horizon Therapeutics, now a subsidiary of pharmaceutical giant Amgen, is the central defendant. No settlement has been reached.

What Is the Tepezza Lawsuit About?

Tepezza (teprotumumab-trbw) is an FDA-approved biologic therapy for thyroid eye disease, a condition linked to Graves' disease in which the immune system attacks tissue behind the eyes. The FDA approved Tepezza in January 2020, and Horizon Therapeutics rapidly built it into one of the pharmaceutical industry's top-selling drugs - peaking at more than $1.6 billion in annual revenue.

Plaintiffs in the lawsuits allege they were not adequately warned that Tepezza can cause serious and potentially permanent hearing-related side effects. According to the complaints, affected patients experienced sensorineural hearing loss (damage to the inner ear or auditory nerve), tinnitus (ringing or buzzing in the ears), autophony (hearing one's own voice abnormally loudly), and muffled or diminished hearing. Many plaintiffs allege these conditions persisted or became permanent after completing their Tepezza infusion course. The lawsuits claim that Horizon Therapeutics knew or should have known about these risks but failed to adequately disclose them to patients and prescribing physicians.

In October 2023, Amgen completed its $27.8 billion acquisition of Horizon Therapeutics, making Amgen the responsible corporate successor. Both companies deny all allegations. No court has ruled on the merits of the claims.

Who May Have Been Harmed?

The Tepezza MDL consists of individual cases brought by patients who received Tepezza infusions and later developed hearing problems. There is no formal class action - the MDL consolidates individual suits for more efficient pretrial proceedings. Each case is evaluated on its own medical facts.

Patients who may have grounds for a lawsuit include those who:

• Received one or more Tepezza (teprotumumab) infusions for thyroid eye disease
• Subsequently developed sensorineural hearing loss, tinnitus, autophony, or other hearing impairment
• Were not adequately warned of these hearing-related risks before starting treatment

The MDL does not have a public claim form. Affected patients must consult a licensed personal injury attorney to evaluate whether their case may qualify.

Current Case Status

The litigation is consolidated in In re: Tepezza Marketing, Sales Practices, and Products Liability Litigation, MDL No. 3079, before U.S. District Judge Thomas M. Durkin in the Northern District of Illinois in Chicago. As of mid-2026, approximately 277 cases are pending in the MDL, according to the Judicial Panel on Multidistrict Litigation.

Fact discovery closed in May 2025, and the case advanced into the expert discovery phase by mid-2026. Previously scheduled bellwether trial dates - which would have provided benchmark verdicts to guide broader settlement talks - were canceled by the court. Judge Durkin has since ordered the parties to convene regularly to explore a potential resolution. No settlement has been reached or announced as of October 2026.

Notably, in September 2025 the FDA updated Tepezza's prescribing label to include a warning about hearing impairment, a regulatory acknowledgment that the plaintiffs' attorneys point to as validating the core allegations in the lawsuits.

What Could Patients Recover?

Because there is no settlement and no class has been certified, no established compensation fund or fixed payment range exists. In individual pharmaceutical litigation, potential recoveries depend heavily on factors including the severity and permanence of hearing damage, the patient's age and occupation, duration of treatment, and demonstrated impact on quality of life and earning capacity. Outcomes vary widely across individual cases, and any recovery would come either through a negotiated settlement or a jury verdict following trial.

What Should Tepezza Patients Do Now?

Patients who received Tepezza and experienced hearing problems should consult an attorney promptly. State statutes of limitations - deadlines to file a personal injury lawsuit - generally run one to three years from when harm was discovered or reasonably should have been discovered. Missing this window can permanently eliminate the right to seek compensation.

1. Gather your medical records, including Tepezza infusion dates, audiology test results, and any diagnosis of hearing loss or tinnitus.
2. Document the timeline of your symptoms - when they began, their severity, and whether they have persisted.
3. Consult a licensed personal injury attorney experienced in pharmaceutical mass tort litigation. Most accept these cases on a contingency basis, meaning no upfront fees.

There is no public claim form for MDL 3079. Be cautious of any solicitation requesting upfront fees or promising guaranteed outcomes.