An Illinois state judge declared a mistrial Wednesday in a lawsuit alleging that Boehringer Ingelheim's over-the-counter Zantac caused a man to develop prostate cancer. The Cook County Circuit Court jury could not reach a unanimous verdict in Martin Gross's case after signaling they were deadlocked.

Jury Struggles to Reach Consensus

The jury, which had been deliberating since Friday afternoon, indicated several times that they were struggling to fully side with either the plaintiff or Boehringer. Their final note, received around 1 p.m., revealed an 8-4 split and stated they couldn't be swayed without additional evidence.

The two-week trial focused on claims that Boehringer ignored warnings that Zantac's active ingredient, ranitidine, was breaking down into the toxic compound NDMA, leading to Gross's prostate cancer diagnosis in 2016.

 Zantac Cancer Trial : Previous Zantac Cancer Trial Outcomes

Gross's jury is the third in Cook County to hear a Zantac cancer case. Earlier this week, a jury rejected plaintiff Carrie Joiner's colorectal cancer claims against GlaxoSmithKline. In May, both GlaxoSmithKline and Boehringer prevailed as co-defendants in Angela Valadez's similar lawsuit.

These cases are part of a larger wave of litigation against GSK and other drugmakers following the U.S. Food and Drug Administration's September 2019 warning about NDMA in Zantac. The FDA ordered the removal of all ranitidine products from the market in April 2020.

Gross’s Claims Against Boehringer

At trial, Gross argued that internal communications from Boehringer indicated the company should have known about the carcinogenic impurity in its heartburn medication well before the FDA’s warning. Gross's counsel cited a 2007 email from a Boehringer executive questioning why some Zantac tablets were darkening after two years, a phenomenon later linked to ranitidine degradation.

Kenzo Kawanabe, Gross’s attorney, stated that Boehringer conducted tests in 2010 but never determined a definitive cause for the discoloration. It wasn't until after the federal recall that Boehringer's risk assessment revealed a high risk of NDMA in Zantac.

 Zantac Cancer Trial : Boehringer's Defense

Boehringer's counsel, Ursula Henninger, argued that Gross's claims lacked scientific support. She emphasized that no evidence ties Zantac discoloration and degradation to NDMA production or that Zantac is a recognized risk factor for prostate cancer. Henninger pointed out Gross's other risk factors, including age, race, weight, and smoking history.

Henninger also refuted the claim that Boehringer could have detected NDMA in Zantac earlier, asserting that the technology used to find NDMA in 2019 did not exist before then.

Broader Zantac Litigation Landscape

Litigation against GSK and other Zantac manufacturers continues in state and federal courts nationwide. The Judicial Panel on Multidistrict Litigation consolidated several personal injury cases in the Southern District of Florida in February 2020. The MDL judge dismissed all claims against Pfizer, GlaxoSmithKline, Boehringer Ingelheim, and Sanofi in December 2022, citing insufficient scientific evidence that ranitidine causes cancer.

Despite a major settlement agreement by Sanofi to resolve approximately 4,000 claims, thousands of lawsuits remain pending in Delaware. Superior Court Judge Vivian L. Medinilla is reviewing expert testimony challenges similar to those that led to the Florida case dismissals.

Legal Representation

Gross is represented by Kenzo Kawanabe, Sean Grimsley, Abigail Hinchcliff, and Samara Hoose of Olson Grimsley Kawanabe Hinchcliff & Murray LLC. Boehringer is represented by Ursula Henninger, Cory Hohnbaum, and Christopher Eby of King & Spalding LLP.