Sanofi agrees to settle antitrust case in US over diabetes drug Lantus

By Reuters News20:37 (UTC), 28 October 2026 Updated

By Nate Raymond

BOSTON, Oct 28 (Reuters) - Sanofi SASY.PA has reached a tentative settlement to resolve long-running claims by drug wholesalers that the pharmaceutical company used an improper patent listing to suppress competition to its diabetes treatment Lantus.

Lawyers for a group of drug purchasers told a federal judge in Boston in a filing on Tuesday that they had reached an agreement in principle to resolve the antitrust case, which had been set for trial in January.

The plaintiffs included the three largest US drug wholesalers, Cencora COR.N, Cardinal Health CAH.N and McKesson MCK.N, along with other purchasers including FWK Holdings and Meijer. They alleged Sanofi's conduct forced them to pay inflated prices for medications.

Terms of the settlement are confidential, Sanofi said in a statement on Wednesday.

"Importantly, we have reached this agreement without any concession of liability, and we continue to maintain that any claims Sanofi’s conduct delayed competition for Lantus SoloStar pens are without merit," Sanofi said.

Thomas Sobol, a lawyer for the plaintiffs at Hagens Berman Sobol Shapiro, did not respond to a request for comment.

The lawsuit was filed in 2016 as a proposed class action but was restructured in 2022 to become a joint action by individual purchasers, with plaintiffs lawyers citing unique attributes of the market for the treatment for the tactical shift.

The plaintiffs claimed Sanofi abused the process for listing patents in the US Food and Drug Administration's Orange Book, a database of brand-name drug patents.

Under the Hatch-Waxman Act, a brand-name drug company has the right to sue a company that applies to make a generic version of a drug if an active patent is listed in the Orange Book as covering it, and the FDA is automatically blocked from approving the generic for 30 months once the patent is asserted.

Sanofi first obtained approval from the FDA to market Lantus for management of diabetes in 2000.

The original patent on its active ingredient, insulin glargine, expired in 2014, and had Sanofi not submitted anything else for inclusion in the Orange Book, generic drugmakers could have sought FDA approval to sell their own versions as early as 2015.

But the plaintiffs alleged Sanofi erected a regulatory roadblock by unlawfully listing other patents in the Orange Book that did not meet the Hatch-Waxman Act's criteria, delaying full competition until at least 2020.

The case is In re Lantus Direct Purchaser Antitrust Litigation, US District Court for the District of Massachusetts, No. 16-cv-12652.

For the plaintiffs: Thomas Sobol and Kristen Johnson of Hagens Berman Sobol Shapiro

For Sanofi: John Majoras, Julie McEvoy and Rosanna McCalips of Jones Day

Sanofi loses bid to trim Lantus antitrust claims