Tepezza Lawsuit Alleges Infusion Side Effects Caused Hearing Loss, Tinnitus

Horizon Therapeutics USA, Inc. has filed a motion to dismiss a hearing loss and tinnitus lawsuit over Tepezza side effects, arguing that it should not face liability for failing to warn about the side effects associated with it’s relatively new treatment for thyroid eye disease, which is also commonly referred to as “bulging eye disease”.

The complaint (PDF) was first filed by Daniel Weibel in late August, in the U.S. District Court for the Northern District of Illinois, indicating he developed permanent hearing loss from Tepezza after receiving the infusions from June 2020 through September 2020.

In response to the Tepezza lawsuit, Horizon filed a Motion to Dismiss (PDF) last week, arguing that the plaintiff failed to establish that the FDA would have allowed the drug maker to add hearing loss warnings to Tepezza, suggesting that the failure to warn claims are pre-empted by federal law.

Tepezza Hearing Loss and Tinnitus Side Effects

Tepezza (teprotumumab-trbw) is a biologic treatment approved by the FDA in January 2020, as the first drug approved to treat thyroid eye disease, which is caused by hyperthyroidism and linked to Graves’ disease, causing inflammation of eye muscles, eyelids, tear glands and fatty tissues behind the eye. This can lead to blurred or double vision and can cause the eyes to appear to bulge.

The FDA allowed Tepezza’s approval through a fast-track Orphan Drug designation, which introduces new medications without extensive testing when they target a condition which has no other treatment available. However, Weibel claims Horizon knew or should have known that Tepezza causes hearing loss before it was ever submitted to the FDA, and aggressively marketed the drug shortly after it was approved, without warning users or the medical community about the importance of monitoring for hearing loss or ear damage.

Horizon submitted Tepezza for FDA approval based on a limited study involving less than 100 patients. While clinical trial data did suggest that 10% of individuals treated with Tepezza suffered hearing impairment, including deafness in some cases, Weibel claims that the drug maker falsely classified the Tepezza hearing problems as temporary or of a limited duration.

Weibel indicates that shortly after the drug was introduced, studies and case reports began to be published that highlighted the potential link between Tepezza and hearing damage, in many cases worsening as additional infusions were administered.

“Upon information and belief, had Defendant exercised reasonable care in testing and studying Tepezza, they would have discovered prior to seeking FDA approval that Tepezza can cause serious and irreversible hearing loss and/or tinnitus,” according to the complaint.

Insufficient Tepezza Warnings

Weibel, of Arizona, received Tepezza infusions intravenously from June 2020 through September 2020 for the treatment of thyroid eye disease. His lawsuit claims that as a result of those infusions, he now suffers permanent hearing loss.

“Defendant continues to represent the majority of hearing-related adverse events in the pivotal trials and post-approval have been mild to moderate and reversible,” Weibel’s lawsuit states. “In contrast to the public statements, almost immediately after the FDA approved Tepezza, patients and doctors began reporting serious complications related to ear and permanent hearing problems in patients taking Tepezza.”

The lawsuit notes that even post-marketing studies provided more evidence Tepezza hearing problems were long-lasting and permanent, at which time the manufacturer should have added additional label warnings, if not before.

“Nevertheless, Defendant failed to warn, instruct, advise, educate, or otherwise inform Tepezza users, Tepeza prescribers, or United States governmental regulators about the risk of hearing loss, or the need for medical, audiological monitoring,” according to the complaint.

Weibel presents claims of failure to warn, design defect, negligent failure to warn, and negligent design. He seeks both compensatory and punitive damages.

November 2022 Tepezza Lawsuit Update

In response to the lawsuit, Horizon filed an early motion to dismiss claiming it could not have unilaterally changed the Tepezza label warning after the FDA approved it, based on the evidence collected during the post-marketing studies. The drug maker claims the complaint does not constitute plausible claims for failure to warn and design defect under Arizona state law, and that punitive damages are not allowed under Arizona law for FDA-approved drugs.

It is expected this may be the first of what could be dozens of Tepezza lawsuits filed in the coming weeks and months, as more individuals learn there may be a link between hearing damage symptoms experienced and the thyroid eye disease infusion treatment.

Tepezza is an insulin-like growth factor 1 receptor (IGF-IR) inhibitor medication, and it is well known that IGF-I is crucial to protecting the inner ear hair cells from noise-induced hearing damage, ischemia and medication toxicity. Therefore, Tepezza lawsuits will involve claims the drug maker knew or should have known about the hearing loss risks, and withheld accurate information from the FDA, consumers and the medical community.

Weibel and other potential plaintiffs maintain that if warnings and instructions about the importance of monitoring for hearing loss on Tepezza had been provided, permanent ear damage may have been avoided.

Product liability lawyers are currently investigating whether individuals may be eligible for a Tepezza hearing loss lawsuit payout if they were diagnosed with tinnitus or any degree of hearing loss that was not experienced before receiving the infusion.