Tepezza Litigation Updates: Establishment of a Multidistrict Litigation

Tepezza Litigation: MDL Establishment and Updated FDA Warnings 

Significant advancements have transpired in the ongoing Tepezza litigation. 

Formation of an MDL: On June 2, 2023, the Judicial Panel on Multidistrict Litigation (JPML) mandated the formation of multidistrict litigation (MDL) concerning Tepezza. The JPML selected the Honorable Judge Thomas Durkin of the Northern District of Illinois to preside over the MDL, which, as of August 15, 2023, comprises 46 individual cases. 

FDA Warning Label Update: After this, on July 24, the U.S. Food and Drug Administration (FDA) revised the warning label guidelines for Tepezza, mandating the inclusion of a warning pertaining to the risk of hearing impairment or hearing loss. This update reflects concerns regarding the potential adverse effects associated with the medication. 

Plaintiffs’ Allegations: The plaintiffs have presented allegations suggesting that Horizon Therapeutics, the manufacturer of Tepezza, was cognizant of the substantial risks associated with the drug, particularly in relation to hearing loss and tinnitus, but did not adequately communicate these risks to the FDA prior to or following the drug’s approval, nor did they sufficiently update the drug’s labeling to inform healthcare providers and patients. They contend that this omission constitutes a “failure to warn” and also assert that the drug possesses inherent safety issues, aligning with the “design defect” theory of liability. 

Horizon’s Stance: Horizon Therapeutics has countered, asserting that the warnings provided upon FDA approval in 2020 were adequate and that the subsequently identified concerns regarding hearing loss and tinnitus were not substantial enough to warrant an immediate change to the drug’s labeling. 

Impact of FDA Label Change: The FDA’s decision to modify the label on July 24, 2023, to include the exact warnings regarding hearing loss and the necessity for vigilant physician monitoring that the plaintiffs argued should have been included initially, is noteworthy. The revised labeling now clearly states the risks of severe hearing impairment, potentially altering the landscape of ongoing and future claims associated with the drug’s use. 

The updated label is available for review at: Tepezza Prescribing Information. 

The change in labeling is likely to have a dual effect: it may limit new “failure to warn” claims post-July 24, 2023, and it is expected to prompt more thorough discussions between physicians and patients about the risks associated with Tepezza. Moreover, this amendment fortifies the position of individuals who used Tepezza prior to these warnings, challenging Horizon’s defense against “failure to warn” claims before the label change. 

Horizon’s legal strategy regarding these preemption defenses remains unchanged as the briefing period continues. Upcoming oral arguments will be pivotal in discerning Judge Durkin’s perspective on these preemption issues and Horizon’s approach considering the updated warning. 

Progress Toward Bellwether Plan: According to a Joint Status Report filed on July 24th, the involved parties have expressed their intention to convene and forge a path toward a mutually agreeable Bellwether/Briefing Plan. This plan will encompass motions to dismiss and the initial selection of bellwether discovery cases. The subsequent status conference is scheduled with Judge Durkin on August 31, 2023. 

Amgen’s Proposed Acquisition of Horizon: In a related development, Amgen has expressed an intent to purchase Horizon for $27.8 billion (about $86 per person in the US). The transaction was initially deferred due to a lawsuit filed by the Federal Trade Commission (FTC) aimed at blocking the acquisition. Following a settlement with the FTC, the companies are now progressing toward finalizing the acquisition. The outcome of this purchase is anticipated to have a significant influence on the Tepezza litigation and its potential resolution. 

Potential Claimant Pool: Current data indicates that the pool of potential claimants is relatively limited, with only 14,500 patients having undergone treatment with Tepezza, as stated on the official product website. The treatment involves a series of infusions over approximately five months. The smaller number of potential claimants may influence the average settlement amount in any prospective collective settlement arrangement.