FDA Adds Tepezza Hearing Loss Warnings to Thryoid Eye Disease Drug’s Label

As Horizon Pharmaceuticals faces a growing number of lawsuits over Tepezza hearing loss, alleging that the drug maker failed to adequately warn users or the medical community about risks associated with their new-generation thyroid eye disease treatment, federal regulators have announced a warning label update which now discloses side effects of Tepezza may cause severe and permanent hearing damage.

Tepezza (teprotumumab-trbw) was introduced in January 2020, as the first medication for bulging eyes and double vision that results from thyroid eye disease. These conditions are caused by hyperthyroidism and linked to Graves’ disease, resulting in inflammation of eye muscles, eyelids, tear glands and fatty tissues behind the eye.

Although Tepezza was considered a niche treatment, Horizon Therapeutics quickly pushed the drug to blockbuster status shortly after it was approved, resulting in sales that exceed $1 billion per year. However, concerns quickly emerged about the potential Tepezza hearing side effects and whether the drug maker sufficiently researched their treatment or disclosed the risks that consumers may face following treatment.

The U.S. Food and Drug Administration (FDA) released a new version of the Tepezza prescribing information guide (PDF) on Thursday, adding a new section to the warnings and precautions section about the risk of severe hearing loss that may be permanent in some cases. The new Tepezza hearing loss warnings also now indicate doctors should assess patients’ hearing before, during, and after Tepezza infusions.

Tepezza Lawsuits Over Hearing Loss

The warnings update comes after dozens of former users filed product liability lawsuits against Horizon, alleging they have been left with irreversible hearing problems from Tepezza side effects, which was not adequately disclosed on the initial warning labels. Plaintiffs maintain they could have avoided permanent damage to their ears if Horizon Therapeutics had provided earlier warnings about the importance of monitoring hearing before and during treatments.

The FDA-approved Tepezza label now includes a new section, which contains nearly identical warnings to those plaintiffs claim Horizon Therapeutics should have provided when the drug was first introduced.

“Tepezza may cause severe hearing impairment including hearing loss, which in some cases may be permanent,” the new Tepezza label warning indicates. “Assess patients’ hearing before, during, and after treatment with Tepezza and consider the benefit-risk of treatment with patients.”

While permanent hearing damage has been linked to Tepezza since its clinical trials, according to various lawsuits filed against the manufacturer, Horizon Therapeutics, the company has resisted calls to add a hearing loss warning to the label.

The warning update comes after a recent study published in the medical journal Endocrine Practice, which found that more than 16% of those who took the thyroid eye disease drug suffered hearing problems, including hearing loss, tinnitus, autophony and eustachian tube dysfunction.

Lawsuits Allege Tepezza Hearing Loss Side Effects Were Ignored

Lawsuits filed against Horizon Therapeutics allege the drug maker knew or should have known that Tepezza causes hearing loss before it was ever introduced, since the drug works by blocking a protein called IGF-1R, which can harm hair cells responsible for hearing and balance. Hair cells in the inner ear play a crucial role in detecting sound waves and transmitting them to the brain, and damaged hair cells can lead to hearing loss and other auditory issues.

Although Horizon Therapeutics was aware this mechanism of action may lead to hearing loss problems among users of the thyroid eye disease drug, the lawsuits claim the drug maker failed to conduct proper follow up or disclose the potential side effects.

Tepezza was submitted to FDA for approval using less than one hundred patients enrolled in clinical trials, according to the complaints, which indicate that Horizon Therapeutics attempted to ignore the problems and placed its desire for profits before the safety of consumers.

Amid aggressive marketing that pushed use of Tepezza infusions that carried inadequate warning labels, lawsuits point out that sales doubled to $1.66 billion during the second year the drug was on the market in the U.S., making early users uninformed test subjects.

July 2023 Tepezza Lawsuits Update

Hundreds of former users are now coming forward to report that they experienced various forms of hearing loss from Tepezza, including persistent ringing in the ears known as tinnitus, and complete hearing loss. In many cases, the problems persist long after the thyroid eye disease treatments, leaving users with irreversible hearing damage.

Given common questions of fact and law raised in complaints filed in federal courts nationwide, a Tepezza MDL (multidistrict litigation) was established last month, centralizing the lawsuits before U.S. District Judge Thomas Durkin in the Northern District of Illinois for coordinated discovery and pretrial proceedings.

As part of the litigation, it is expected that a “bellwether” program will be established, where a small group of representative cases will be selected to go through case-specific discovery in preparation for early trial dates, which will help the parties gauge how juries are likely to respond to certain evidence and testimony that will be repeated throughout various cases in the litigation.

Following coordinated discovery and trials in the MDL, if the parties fail to reach a Tepezza settlement agreement or other resolution for the litigation, each individual claim may later be remanded back to the U.S. District Court where it was originally filed for trial.