After more than a year of signaling that settlement was likely, Sanofi-Aventis US LLC and Sanofi US Services Inc. have struck agreements in two Connecticut lawsuits claiming that the blockbuster heartburn medication Zantac and its generic equivalents degraded into a cancer-causing compound.

Notices filed Thursday in the Waterbury Judicial District confirm that the French drugmaker reached settlements in principle in both cases — one involving six plaintiffs and the other involving 10 plaintiffs. Terms of the accords remain under wraps. The filings state that the cases will be withdrawn once the settlements are formalized.

A Legal Fight Over Innovator Liability

The lawsuits revolved around a contentious legal theory known as innovator liability, which seeks to hold brand-name manufacturers accountable for injuries allegedly caused by generic versions of their drugs. Plaintiffs argue that because the big pharmaceutical companies control the warning labels, they should bear responsibility regardless of which pill a consumer actually took.

Last year, Sanofi told Judge W. Glen Pierson that a ruling on innovator liability would help steer talks toward resolution. In August 2023, Pierson ruled that Sanofi could be sued in Connecticut courts, but left the thorny liability issue unresolved, saying it would need to be addressed later in litigation.

Sanofi Maintains Its Position

Throughout the proceedings, Sanofi has stood firm on its defense. The company has consistently argued that there is “no reliable scientific evidence” linking Zantac to cancer.

Still, the drugmaker has been pursuing settlements nationwide. In April 2024, Sanofi said it was working to resolve around 4,000 similar cases across the U.S. The Connecticut deals mark a notable step in that broader effort.

Other Drugmakers Under Pressure

Sanofi is not alone in facing claims tied to Zantac. GlaxoSmithKline (GSK) reached its own settlements in June this year to resolve its portion of the same Connecticut cases.

The plaintiffs in the Connecticut suits are represented by Brenden P. Leydon of Wocl Leydon LLC. Sanofi is represented by Joseph W. Martini and Armel L. Jacobs of Spears Manning & Martini LLC.

A Nationwide Litigation Landscape

The Connecticut settlements are only part of a sprawling wave of litigation testing the boundaries of liability in pharmaceutical law. With thousands of cases pending in courts nationwide, the Sanofi Zantac cancer suit continues to be a bellwether for how courts — and companies — will navigate allegations that strike at the intersection of medicine, science, and corporate accountability.