• Home
  • Latest
  • Fortune 500
  • Finance
  • Tech
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
FinanceBayer
Europe

Bayer had its worst day ever as shares sunk to the lowest in over a decade on $1.5bn Roundup verdict and drug failure

By
Tim Loh
Tim Loh
and
Bloomberg
Bloomberg
Down Arrow Button Icon
By
Tim Loh
Tim Loh
and
Bloomberg
Bloomberg
Down Arrow Button Icon
November 20, 2023, 5:43 AM ET
Bill Anderson, chief executive officer of Bayer AG
Bill Anderson, chief executive officer of Bayer AG.Krisztian Bocsi—Bloomberg/Getty Images

Bayer AG suffered its biggest drop ever, losing about €7.6 billion ($8.3 billion) in market value, after major legal and drug-development setbacks that raise pressure on its new leader to outline a turnaround plan.

The German pharma and agriculture company stopped the main study of its top experimental medicine due to a lack of efficacy and lost a key US trial against its weed killer Roundup. The shares fell as much as 19% in Frankfurt trading to the lowest level in more than a decade. 

The events raise the stakes for Bill Anderson, who took over as chief executive in June and said this month he’s weighing a breakup of the pharma and agriculture conglomerate. 

Anderson joined as Bayer confronts a thicket of challenges after the $63 billion takeover of Monsanto turned sour and its pharma unit faces patent expirations for some key treatments.

The German company said Sunday it had ended a late-stage test for the anti-thrombotic drug asundexian — a therapy billed as a potential blockbuster — due to a lack of efficacy. 

“Asundexian was the pearl of Bayer’s pharma pipeline,” said Markus Manns, a portfolio manager at Union Investment and a shareholder. Bayer should have found a partner to share development costs and risks with, he said. 

Roundup Verdicts

The announcement came two days after Bayer’s Monsanto unit was ordered by a Missouri jury to pay more than $1.5 billion to three former Roundup users who blamed their cancers on the controversial product in one of its largest trial losses over the herbicide.

Monsanto has been hit with a recent spate of jury verdicts finding Roundup contains carcinogens. The more than $1.5 billion verdict is one of the largest damage awards handed down against a US corporate defendant this year.

Bayer said it will appeal the verdicts and insists the product is safe. Two years ago, the company set aside as much as $16 billion to resolve more than 100,000 cases over Roundup’s health impact. 

The conglomerate now faces a second wave of lawsuits. The legal risks could complicate Anderson’s efforts to spin off the agriculture division, if he opts for that path, Sebastian Bray, an analyst with Berenberg, said in an email.

Bayer is currently in another Roundup trial before a state court jury in Philadelphia involving a man who blames the weed killer for his cancer. The jury is still hearing evidence and closing arguments in the case aren’t expected until later this month or in early December, according to lawyers involved in the case.

Another case is scheduled to start in California in December, with at least three other cases slated to begin in Philadelphia in coming months.

Aging Drugs

The experimental drug that failed, asundexian, was intended to help drive growth after current best-selling medicines Xarelto and Eylea lose their patent protections in coming years.

An independent panel found the treatment underperformed the standard of care when it came to preventing stroke and systemic embolism in patients with a form of abnormal heart rhythm called atrial fibrillation.

The indication represented about €4 billion of the estimated €5.5 billion in peak sales for the drug, Thibault Boutherin and colleagues at Morgan Stanley said in a note Monday. They called the study decision “a meaningful negative.” 

Bayer will continue another study with asundexian for preventing strokes, though the market opportunity is smaller, the analysts noted. It will also need to decide whether to move forward with a test in elderly patients, they said.

Join us at the Fortune Workplace Innovation Summit May 19–20, 2026, in Atlanta. The next era of workplace innovation is here—and the old playbook is being rewritten. At this exclusive, high-energy event, the world’s most innovative leaders will convene to explore how AI, humanity, and strategy converge to redefine, again, the future of work. Register now.
About the Authors
By Tim Loh
See full bioRight Arrow Button Icon
By Bloomberg
See full bioRight Arrow Button Icon

Latest in Finance

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025

Most Popular

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Fortune Secondary Logo
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • Future 50
  • World’s Most Admired Companies
  • See All Rankings
Sections
  • Finance
  • Fortune Crypto
  • Features
  • Leadership
  • Health
  • Commentary
  • Success
  • Retail
  • Mpw
  • Tech
  • Lifestyle
  • CEO Initiative
  • Asia
  • Politics
  • Conferences
  • Europe
  • Newsletters
  • Personal Finance
  • Environment
  • Magazine
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
  • Group Subscriptions
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • Facebook icon
  • Twitter icon
  • LinkedIn icon
  • Instagram icon
  • Pinterest icon

© 2026 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.


Latest in Finance

workers
AIdisruption
A Yale economist says AGI won’t automate most jobs—because they’re not worth the trouble
By Nick LichtenbergApril 4, 2026
2 hours ago
MUSCAT, OMAN - Locals visit Muscat Anchorage near the Strait of Hormuz on March 30, 2026 in Muscat, Oman. Several Chinese-owned vessels were reportedly able to transit the Strait of Hormuz today, the day after U.S. President Donald Trump said Iran would allow 20 ships to cross through the vital waterway. (Photo by Elke Scholiers/Getty Images)
EnergyIran
Iran’s military may be decimated, but it’s winning the energy war as it controls who gets cargoes through the Strait of Hormuz
By Jordan BlumApril 4, 2026
3 hours ago
rick steves holds american flag
PoliticsTaxes
Travel guru Rick Steves is happy to pay more taxes
By Catherina GioinoApril 3, 2026
10 hours ago
Checking a bag on United Airlines now costs $10 more as Iran war sends jet fuel costs up nearly 100% in major hubs
Travel & LeisureAir Travel
Checking a bag on United Airlines now costs $10 more as Iran war sends jet fuel costs up nearly 100% in major hubs
By Rio Yamat and The Associated PressApril 3, 2026
11 hours ago
At least one crew member still missing after Iran shoots down 2 U.S. aircraft while Trump says ‘it’s war’
PoliticsIran
At least one crew member still missing after Iran shoots down 2 U.S. aircraft while Trump says ‘it’s war’
By Sam Mednick, Konstantin Toropin, Seung Min Kim and The Associated PressApril 3, 2026
11 hours ago
Best certificates of deposit (CDs) for April 2026
Personal FinanceCertificates of Deposit (CDs)
Best certificates of deposit (CDs) for April 2026
By Glen Luke FlanaganApril 3, 2026
14 hours ago

Most Popular

Google CEO Sundar Pichai says we’re just a decade away from a new normal of extraterrestrial data centers
Innovation
Google CEO Sundar Pichai says we’re just a decade away from a new normal of extraterrestrial data centers
By Fortune EditorsApril 3, 2026
24 hours ago
Gen Z fled San Francisco for Texas and Florida. Now they’re turning ‘welcomer cities’ into the next big tech towns
Real Estate
Gen Z fled San Francisco for Texas and Florida. Now they’re turning ‘welcomer cities’ into the next big tech towns
By Fortune EditorsApril 2, 2026
2 days ago
The Walmart billionaires next door: Quiet backlash is brewing against the heirs who remade the retailer’s hometown
Magazine
The Walmart billionaires next door: Quiet backlash is brewing against the heirs who remade the retailer’s hometown
By Fortune EditorsApril 3, 2026
1 day ago
Major 4-day workweek study suggests that when we work 5 days we spend one doing basically nothing
Success
Major 4-day workweek study suggests that when we work 5 days we spend one doing basically nothing
By Fortune EditorsApril 2, 2026
2 days ago
Current price of oil as of April 3, 2026
Personal Finance
Current price of oil as of April 3, 2026
By Fortune EditorsApril 3, 2026
21 hours ago
Current price of silver as of Friday, April 3, 2026
Personal Finance
Current price of silver as of Friday, April 3, 2026
By Fortune EditorsApril 3, 2026
21 hours ago