Bayer shares plunge by more than 20% after trial of potential blockbuster drug halted

Bayer lost a fifth of its market value at one point Monday, after the German pharmaceutical and agricultural group said it had ended a late-stage test for the anti-thrombotic drug asundexian due to a lack of efficacy.

News of the disappointing trial for the hoped-for blockbuster treatment came just two days after Bayer’s XE:BAYN Monsanto unit was ordered by a Missouri jury to pay $1.56 billion to three former users of the group’s Roundup herbicide, which the litigants blamed for their cancer.

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