Tepezza Lawsuits: Hearing Loss Linked to Thyroid Eye Disease Medication
Last Updated on February 27, 2026
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If you still have questions about your rights, contact an attorney in your area as there is a time limit for filing all lawsuits. The information on this page was posted when the investigation began and is now for reference only.
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At A Glance
- This Alert Affects:
- Anyone who received at least three Tepezza treatments and has developed permanent hearing loss or permanent tinnitus (ringing in the ears).
- What’s Going On?
- Tepezza has been linked to potentially permanent hearing loss and other hearing impairments, and lawsuits have been filed claiming the manufacturer did not adequately warn patients about these risks. Attorneys working with ClassAction.org are now filing lawsuits on behalf of Tepezza patients who developed permanent hearing loss or tinnitus.
- How Could a Lawsuit Help?
- A lawsuit could help a Tepezza patient recover money for medical bills, pain and suffering, and other damages related to their injury.
- How Much Does This Cost?
- It doesn’t cost anything to speak to an attorney about your legal options, and you’ll only pay if they win your case. Their payment will be a percentage of your settlement or jury verdict.
Attorneys working with ClassAction.org would like to speak to anyone who has received at least three Tepezza treatments and developed permanent hearing loss or permanent tinnitus (ringing in the ears).
Lawsuits have been filed against the maker of the thyroid eye disease medication alleging the company failed to properly test the product before releasing it to the market. The lawsuits also claim that even though the manufacturer knew – or should have reasonably known – via patient reports, published research and its own post-marketing studies about the risk of permanent and irreversible hearing loss with Tepezza, doctors and patients were not adequately warned about this risk.
You may be able to file a lawsuit to recover money for medical expenses, pain and suffering, and more.
Why Are There Lawsuits About Tepezza?
Lawsuits are now being filed claiming that Tepezza’s manufacturer, Horizon Therapeutics, failed to adequately test the drug prior to putting it on the market and did not properly warn doctors and patients of the known risk that Tepezza could cause adverse effects, including permanent hearing loss and tinnitus.
According to the lawsuits, limited clinical trials for Tepezza revealed that as many as 10 percent of patients experienced hearing issues, including tinnitus and hearing loss, after receiving treatments. However, a more recent study presented at the Endocrine Society’s 2021 meeting found that the rate of patients who experience otologic symptoms — including hearing loss, tinnitus, ear plugging or other hearing dysfunction, after receiving Tepezza treatments — could be as high as 65 percent.
The lawsuits claim Horizon did not conduct enough tests to determine Tepezza’s mechanism of action or long-term side effects prior to its approval and that the company misrepresented to the FDA that the hearing loss reported during clinical trials was only temporary.
In the summer of 2023, the FDA updated Tepezza’s label to include a warning that the drug could cause “severe hearing impairment including hearing loss, which in some cases may be permanent.”
Who Can File a Tepezza Lawsuit?
If you have received at least three Tepezza treatments and have developed permanent hearing loss or permanent ringing in the ears, you may qualify to file a Tepezza lawsuit.
Is This a Tepezza Class Action Lawsuit?
No. Attorneys working with ClassAction.org are handling Tepezza hearing loss lawsuits on an individual basis — and not as a class action lawsuit. This is because they’re working with patients who claim to have developed deafness and other injuries serious enough to warrant individual lawsuits.
Typically, in a class action lawsuit, the person filing the case is seeking compensation for a relatively small harm — say, the cost of purchasing a shampoo that didn’t work as advertised — on behalf of themselves and a larger group of consumers as it wouldn’t be cost effective to bring an individual case over such an injury. Click here to learn more about why lawsuits involving dangerous drugs or defective medical devices are not typically handled on a class action basis.
For a Tepezza personal injury case, you would need to file your own lawsuit and be represented by your own attorney, who would gather information about your case, file a complaint describing your injuries and the damages you’re seeking, and attempt to resolve the matter on your behalf.
How Much Does a Tepezza Lawyer Cost?
Most attorneys handling Tepezza lawsuits, including those working with ClassAction.org, are operating on a contingency-fee basis. This means you only pay if they win your case, and their payment will come as a percentage of your settlement or jury verdict.
Is There a Deadline to File a Tepezza Lawsuit?
Each state has its own statute of limitations for filing a civil lawsuit, including cases stemming from alleged Tepezza injuries. This is one of the reasons why it is important to contact an attorney about your legal options as they will know more about any specific Tepezza lawsuit deadlines in your state.
Has There Been a Tepezza Lawsuit Settlement?
To date, no settlement has been reached in a Tepezza hearing loss lawsuit. The litigation continues to grow as more and more cases are filed in the Tepezza multidistrict litigation (MDL), and ClassAction.org will update this page with any significant developments, including in the event of a Tepezza settlement, so be sure to check back often.
What Kind of Payout Could I Get From a Tepezza Lawsuit?
Though each case is different, you could potentially file a lawsuit to recover money for your medical bills, the pain and suffering you’ve experienced, lost wages and decreased quality of life.
Some have estimated that the potential payout from a Tepezza lawsuit could range anywhere from $140,000 to $250,000, though it is nearly impossible to predict how much, if anything, a Tepezza hearing loss settlement might be worth, especially since the Tepezza MDL is relatively new.
The amount of any Tepezza settlement will depend on, among other factors, the age of a Tepezza patient, whether they have preexisting hearing problems and the extent of any hearing damage potentially linked to the treatment. It is possible that a potential Tepezza settlement over hearing loss in a younger patient could be worth more than a payout to an older plaintiff.
Ultimately, only a qualified lawyer will be able to provide insight on the amount of any potential payout you might receive from a Tepezza lawsuit.
What Is Tepezza?
Tepezza is the brand name version of teprotumumab and the first drug approved by the U.S. Food and Drug Administration (FDA) to treat thyroid eye disease in adults.
Tepezza is manufactured by Horizon Therapeutics and was approved by the FDA in January 2020. The biologic treatment is administered intravenously as an infusion, most commonly by a registered nurse, once every three weeks for a total of eight infusions over roughly five months. Tepezza helps decrease inflammation behind the eye by blocking insulin-like growth factor-1 (IGF-1) receptors. Studies have shown that IGF-1 plays a central role in hearing and protecting the inner-ear hair cells from noise-related damage.
Tepezza is a relatively expensive treatment since, at present, there can be no generic version of the drug.
How Could Tepezza Potentially Cause Hearing Loss?
Low levels of IGF-1 have been associated with hearing loss, and one recent study concluded that teprotumumab’s inhibition of IGF-1 and its receptor pathway could result in irreversible, permanent hearing loss.
Is Tepezza Hearing Loss Permanent?
According to an FDA label update—and even the official Tepezza website—hearing loss linked to Tepezza may not be reversible and can be permanent.
Some patients, however, have reported experiencing only partial hearing loss or that their hearing loss symptoms improved within a few months.
What Are Some Tepezza Hearing Loss Side Effects?
Although milder side effects such as muscle spasms, nausea, fatigue, headaches, dry skin, diarrhea and loss of taste, among others, have been linked to Tepezza infusions, more concerning is that, according to medical research and the drug’s label, temporary or permanent hearing loss is among the side effects of Tepezza.
Other potentially serious hearing-related side effects have been associated with the treatment. These Tepezza hearing-loss side effects can include, but are not limited to:
- Sensitivity or low tolerance to sounds, a condition known as hyperacusis;
- An inability to hear clearly or a partial loss of hearing, a condition known as hypoacusis;
- Hearing one’s own voice or breathing more loudly or with an echo, a condition known as autophony; and
- Tinnitus, or ringing in the ear.
Some Tepezza patients may experience a combination of these symptoms.
Other Tepezza side effects can reportedly include high blood sugar and allergic reactions.
How Long Do Tepezza Hearing Loss Side Effects Last?
Medical News Today shares that there is no concrete timeline for how long potential side effects from Tepezza may last, as side effects could subside over the course of a person’s treatment or continue months after treatment.
However, some patients have claimed to have developed permanent hearing loss and/or tinnitus after receiving Tepezza infusion treatments.
If you are experiencing side effects from Tepezza, contact your healthcare provider as soon as possible.
What Is Thyroid Eye Disease?
Thyroid eye disease (TED) is a relatively rare, non-contagious autoimmune condition primarily associated with an overactive thyroid gland that causes swelling and damage to the fatty and connective tissues around the eye.
Researchers are still investigating the root cause of thyroid eye disease, but it’s believed that the condition is mainly caused by the stimulation of thyroid-stimulating hormone receptors, which are located in the thyroid gland but also exist in the tissues around the eyes. In thyroid eye disease, the immune system mistakenly attacks both the thyroid gland and the body fat and tissues around the eyes, leading to TED symptoms like swelling and inflammation.
The two phases of thyroid eye disease are an active, or inflammatory, phase and a stable phase. Active thyroid eye disease can last anywhere from months to years, with the stable phase coming after inflammation has gone down.
Per the FDA, thyroid eye disease impacts women more frequently than men, and roughly 90 percent of all thyroid eye disease cases occur simultaneously with Graves' disease, an autoimmune disorder that can affect the thyroid, eyes and skin.
While both hyperthyroidism—meaning the body releases too many thyroid hormones—and, less commonly, hypothyroidism—too few thyroid hormones—can cause thyroid eye disease, it can also occur in people with normal thyroid hormone levels.
What Are the Symptoms of Thyroid Eye Disease?
The symptoms of thyroid eye disease can include:
- Dry eyes;
- Watery eyes;
- Irritated, gritty-feeling eyes;
- Bulging eyes, a condition called proptosis;
- Double vision;
- Swollen eyelids;
- Sensitivity to light;
- Pain behind the eyes;
- Pain during eye movements; and
- Difficulty closing the eyes completely.
These symptoms may affect one or both eyes.
May 2024
Tepezza MDL Update – 113 Hearing Loss Lawsuits Pending
As of May 1, 2024, the Tepezza multidistrict litigation over hearing loss-related injuries contains a total of 113 cases.
April 2024
101 Tepezza Lawsuits Pending in MDL
As of April 1, 2024, there are 101 lawsuits pending in the multidistrict litigation (MDL) formed over Tepezza hearing loss injuries. When the MDL was formed in June 2023, it contained only 54 pending lawsuits.
The lawsuits are overseen by United States District Judge Thomas M. Durkin in the Northern District of Illinois.
March 2024
Tepezza Bellwether Selection Process Kicks Off
On March 1, 2024, the plaintiffs in the Tepezza MDL selected four bellwether lawsuits, with Horizon Pharmaceuticals to choose four more, to kick off the bellwether selection process in the litigation. From there, the court will randomly choose the final four bellwether cases and the parties will begin case-specific discovery—the process whereby attorneys exchange information about witnesses and evidence—prior to beginning the actual bellwether trials.
In multidistrict litigation, a judge may order several cases to be tried individually, effectively as “test runs” meant to produce meaningful information and experience to the parties in the MDL and help indicate how the litigation might resolve. Bellwether trials may also provide some insight as to any potential Tepezza settlement amounts, should the litigation be resolved via settlement.
In bellwether trials, attorneys generally come to learn the strengths and weaknesses of their legal arguments and could come away with insight as to how a jury might rule.
The results of bellwether trials are not binding on other plaintiffs in an MDL, and bellwether cases may be used by attorneys to hash out a settlement.
December 2023
Tepezza MDL Grows to More Than 70 Hearing Loss Lawsuits
As of December 15, 2023, the Tepezza hearing loss MDL included 71 cases.
November 2023
Judge Rules Horizon Therapeutics Can Be Sued for Alleged Failure to Design Safer Tepezza Before Seeking FDA Approval
United States District Judge Thomas M. Durkin dismissed Horizon’s contention that it cannot be sued for allegedly failing to design a safer version of Tepezza before seeking FDA approval.
In a November 3 opinion and order, Judge Durkin stated that the plaintiff’s “pre-approval design defect claims” for Tepezza could proceed and rejected Horizon’s argument that a change in Tepezza’s design to meet state law safety requirements would conflict with federal law.
“[T]o the extent that Horizon had a duty under state law to create a safer alternative design, Horizon could have satisfied that duty without coming into conflict with any federal requirement,” the document reads.
Legal experts have said the ruling opens the door for the MDL to explore whether a safer alternative to Tepezza may have been feasible and whether the FDA would have approved it.
September 2023
Following Deal with FTC, Amgen Buys Horizon, Assuming Tepezza Hearing Loss Liabilities
In September 2023, Amgen, Inc. and the Federal Trade Commission (FTC) came to an agreement to allow the global biopharma company to go forward with its acquisition of Tepezza maker Horizon Therapeutics for $27.8 billion.
Amgen’s purchase of Horizon hit a snag months earlier when the FTC sued to block the deal over claims that it would enable the company to leverage its stable of blockbuster drugs to pressure insurance companies and pharmacy benefit managers to favor Tepezza and Krystexxa, a treatment for severe gout.
For the FTC to greenlight Amgen’s Horizon acquisition, Amgen agreed to allow regulators to review its contracts with insurers to prevent “bundling” and consented to other measures in order to prevent anticompetitive behavior.
The Amgen purchase of Horizon Pharmaceuticals, the largest in the former’s history, was formally closed in early October 2023 and gave Amgen access to a dozen top-selling drugs.
July 2023
Tepezza Warning Label Updated to Note Possibility of Permanent Hearing Loss
In July 2023, the FDA updated the warning label for Tepezza to include a new precaution that the thyroid eye disease treatment may cause “hearing impairment including hearing loss.”
Specifically, the new Tepezza hearing loss warning reads: “TEPEZZA may cause severe hearing impairment including hearing loss, which in some cases may be permanent. Assess patients’ hearing before, during, and after treatment with TEPEZZA and consider the benefit-risk of treatment with patients.”
The warning label was updated even though permanent hearing loss had been linked to Tepezza since it underwent clinical trials.
June 2023
Tepezza MDL Is Created to Handle Hearing Loss Lawsuits
On June 6, 2023, the United States Judicial Panel on Multidistrict Litigation (JPML) ordered 37 Tepezza hearing lawsuits pending in eight districts to be centralized in the Northern District of Illinois, thus creating the Tepezza multidistrict litigation, or MDL.
In a three-page MDL transfer order, the JPML, the seven-judge panel tasked with determining whether litigation spanning multiple districts should be centralized for efficiency and resource conservation, found that wrangling the dozens of Tepezza hearing loss lawsuits before one central court would “serve the convenience of the parties and witnesses and promote the just and efficient conduct of the litigation.”
The JPML added that the Tepezza lawsuits were expected to share factual questions linked to the allegations that the treatment can cause permanent hearing loss and tinnitus, and the panel also noted that the plaintiffs have all allegedly suffered “the same signature injuries.”
“Centralization offers an opportunity to substantially streamline pretrial proceedings, reduce duplicative discovery and conflicting pretrial obligations, as well as prevent inconsistent rulings,” the panel reasoned, adding that it was “not persuaded” by Tepezza maker Horizon Therapeutics’ arguments against the centralization of the hearing loss cases.
March 2023
Tepezza Plaintiffs File Motion to Consolidate Hearing Loss Lawsuits in Illinois
On March 22, 2023, the plaintiffs in several Tepezza lawsuits filed a motion to centralize the cases before one court in order to streamline the growing litigation.
March 2023
Stanford Case Study Finds Tepezza Hearing Loss Risk Can Be Reduced with Lower Dosage
A case study from Stanford University found that lower doses of Tepezza, or “half-dose therapy,” could significantly reduce the risk of hearing loss in patients.
The study, published online in the journal Ophthalmic Plastic and Reconstructive Surgery in March 2023, summarizes that a lower dose of Tepezza can be effective for patients with active moderate to severe thyroid eye disease who experience “significant or intolerable adverse events,” including sensorineural hearing loss.
The patient in the study, who initially discontinued Tepezza treatments due to significant hearing loss, tolerated lower-dose infusions once the treatments were restarted a year later “without return of significant sensorineural hearing loss.”
March 2021
Study Finds 65% of Patients Had Hearing Issues After Tepezza Infusions
Endocrine Society published in March 2021 that 65 percent of Tepezza patients in a small study reported experiencing hearing symptoms, such as hearing loss or muffled hearing, after taking infusions of the thyroid eye disease treatment.
In a press release, Endocrine Society, the world’s largest and oldest collective of scientists and physicians devoted to researching and treating hormone-related conditions, said that although otologic symptoms were reported in 10 percent of patients in two clinical trials conducted prior to Tepezza’s FDA approval, the new study found that the rate of hearing issues in Tepezza patients “could be as high as 65 percent.”
Of the 17 patients with new hearing symptoms, Endocrine Society wrote, four had “new or worsening sensorineural hearing loss,” and three had eustachian tube issues whereby the channel running between the middle ear and back of the nose and throat stayed open.
January 2020
Tepezza Approved By FDA to Treat Thyroid Eye Disease
On January 21, 2020, the U.S. Food and Drug Administration (FDA) announced that it had approved Tepezza (teprotumumab-trbw) for the treatment of thyroid eye disease, making Tepezza the first drug approved by the agency to treat the rare, potentially debilitating condition.
In a press release, the FDA called Tepezza’s approval “an important milestone for the treatment of thyroid eye disease” and noted that there existed very few treatment options for TED given the relatively small portion of the population who suffer from the disease. Upon approval, Tepezza was given “orphan drug” designation, as the FDA’s Orphan Drug Program provides grants and other perks to companies to incentivize the development of treatments for rare conditions that impact less than 200,000 people or will most likely not be profitable for at least seven years.
According to the FDA, Tepezza was approved based on the results of two studies that included 170 patients with active thyroid eye disease. The patients were administered either Tepezza or a placebo, and 71 percent of patients in the first study and 82 percent of patients in the second study showed “a greater than 2 millimeter reduction” in eye protrusion in comparison to 20 percent and 10 percent, respectively, of those who received the placebo, the FDA states.
The FDA added that the most common adverse reactions experienced by patients included muscle spasms, nausea, hair loss, diarrhea, high blood sugar, fatigue, dry skin, headaches, an altered sense of taste, and hearing loss.
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