Bayer’s Dual Narrative: A Blockbuster Drug Candidate Emerges as the Supreme Court Weighs Billions in Liability

Bayer battles $10B+ Roundup litigation at Supreme Court while its pharma division posts promising Phase III data for stroke drug Asundexian.

The Leverkusen-based conglomerate is living two very different lives this spring. On one hand, its pipeline is throwing off some of the most encouraging clinical data in years. On the other, the company is locked in a legal battle that could reshape the entire landscape of pesticide litigation in the United States.

On Monday, the US Supreme Court began oral arguments in Durnell v. Monsanto, a case that pits federal regulatory authority against state tort law. The plaintiff, a Missouri man who developed non-Hodgkin lymphoma after years of exposure to the weedkiller Roundup, was awarded $1.25 million by a lower court. Bayer appealed, and the justices agreed to hear the case because the federal appeals courts are deeply split on the central legal question.

That question is deceptively simple: does federal law, as administered by the Environmental Protection Agency, preempt state-law claims when the EPA has declined to require a cancer warning on a product? The Third Circuit says yes, siding with Bayer. The Ninth and Eleventh Circuits say no. The Supreme Court’s decision, expected by the end of June, will settle the matter nationwide.

Bayer has an unexpected ally in the courtroom. The Trump administration, through the Solicitor General, filed a brief supporting Monsanto’s position and secured time to argue during the hearing. On the other side stand consumer advocacy groups and the Make America Healthy Again movement.

The financial stakes are staggering. Roundup-related litigation has already cost Bayer more than $10 billion, and the company’s provisions for future claims stand at nearly €11.8 billion. Of the 28 cases that have gone to trial since 2015, plaintiffs prevailed in 11, according to Bayer’s 2025 annual report.

Alongside the Supreme Court strategy, Bayer is pursuing a parallel settlement track. A Missouri judge has given preliminary approval to a $7.25 billion deal designed to resolve both existing and future glyphosate-exposure claims. Affected individuals have until June 4, 2026, to opt out.

CEO Bill Anderson, who took the helm in mid-2023, has pledged to significantly reduce the mass-tort burden by the end of 2026. A favorable Supreme Court ruling would be his most powerful tool — it would gut the legal theory underpinning thousands of pending cases and send a signal far beyond Roundup alone.

A pipeline that’s finally delivering

While the legal drama unfolds in Washington, Bayer’s pharmaceutical division is producing results that offer a counter-narrative. In April, the company published full Phase III data for Asundexian in the New England Journal of Medicine. The drug, a Factor XIa inhibitor, reduced ischemic strokes by 26 percent compared with placebo — without increasing bleeding risk. It is the first FXIa inhibitor to successfully complete a Phase III trial, and the FDA has granted it Fast Track designation. Analysts see genuine blockbuster potential in secondary stroke prevention.

Bayer’s kidney drug Kerendia (finerenone) is also expanding its reach. The European Commission has approved it for a new indication: heart failure with left ventricular ejection fraction of 40 percent or more. Roughly half of the 15 million Europeans living with heart failure fall into that category. The drug generated €829 million in sales last year, and Bayer sees long-term peak revenue of €3 billion annually. A fifth successful Phase III trial, FIND-CKD, showed that finerenone slows disease progression in non-diabetic chronic kidney disease, and Bayer plans to submit those data to regulators.

The oncology drug Nubeqa grew 57 percent to €2.4 billion. Management has flagged 2026 as the last year of significant headwinds from patent expirations on Xarelto and Eylea.

Cash burn and market sentiment

The pharmaceutical progress is unfolding against a strained financial backdrop. Bayer expects to spend roughly €5 billion on litigation-related payouts this year alone, which will push free cash flow into negative territory — between minus €1.5 billion and minus €2.5 billion.

The stock reflects the uncertainty. Shares trade at around €38.45, roughly 22 percent below the 52-week high of €49.17. Over the past seven days, the stock has shed more than 7 percent. Yet over a 12-month horizon, it has still gained nearly 68 percent — a reminder that investors have been betting on a resolution.

The Supreme Court’s decision in June will determine whether that rally rests on solid ground. If the justices side with Bayer, the legal theory that has fueled the mass tort wave collapses. If they do not, the company will face years more of litigation, with the $7.25 billion settlement serving as the floor — not the ceiling — of its exposure.