Bayer Wins Procedural Round in mRNA Patent Fight as FDA Fast-Tracks Lynkuet

Delaware judge lets Bayer's mRNA patent cases against Pfizer, BioNTech and Moderna proceed; FDA grants Priority Review to Lynkuet.

A federal judge in Delaware has refused to throw out Bayer's patent lawsuits against Pfizer, BioNTech and Moderna, keeping the company's challenge over mRNA technology alive in the United States. Judge William Bryson ruled against the vaccine makers, who had sought an early dismissal of the cases.

Bayer filed the suits in January 2026, alleging that the three rivals infringed a patent held by its Monsanto subsidiary when producing their COVID-19 vaccines. The stabilization technology at the heart of the dispute dates back to the 1980s, when it was originally developed for agricultural use in crops. Bayer contends the competitors' shots rely on that same mechanism without authorization.

Defense Arguments Rejected at Early Stage

Pfizer, BioNTech and Moderna had pushed for a judicial dismissal to halt the litigation before it gathered pace. Bryson found that, at this early procedural stage, the companies had neither demonstrated the patent was invalid nor shown that their vaccines did not infringe it. Spokespeople for the defendants declined to comment immediately after the ruling became known.

The three vaccine developers argue that their own manufacturing processes operate in a fundamentally different way from Monsanto's historical technology. Moderna has added a further line of attack, claiming the patent in question covers merely a natural phenomenon — a law of nature that cannot be patented.

The judge's decision does not amount to a ruling on the merits of the patent claims. It is a procedural step only. Market observers expect a substantive resolution in the main proceedings could stretch over several years, with outcomes ranging from courtroom trials to out-of-court licensing deals.

FDA Grants Priority Review for Lynkuet

On the pharmaceutical front, Bayer has secured a faster path to an expanded approval in the US. The Food and Drug Administration has granted Priority Review to Lynkuet, whose active ingredient is elinzanetant, for an additional indication: treating moderate to severe vasomotor symptoms in women undergoing endocrine therapy for hormone receptor-positive breast cancer. The application rests on clinical data from the Phase III OASIS-4 trial.

Priority Review shortens the FDA's standard review timeline, and is typically reserved for therapies that offer meaningful advantages over existing treatments. For Bayer, the designation marks a significant step in late-stage development and a boost for its medicines division. Hot flashes and night sweats weigh heavily on patients' quality of life, underscoring the need for effective options.

Portfolio Moves Keep Pace

The regulatory news lands alongside a string of operational changes. Bayer sold its cancer drug Stivarga to Grünenthal on September 21, having closed a capital solution for its contraception business on September 16 — both part of a push to concentrate on strategic core areas.

Elsewhere, the company is pressing ahead in consumer health and agricultural innovation. On Wednesday it launched a new mono-material blister in Germany for its stomach remedy Talcid, with a gradual roll-out across eleven European markets planned through 2027. Leaps by Bayer, the group's venture unit, led a financing round at biotech firm Robigo on September 17.

To shore up its capital structure, Bayer placed hybrid bonds totaling EUR 2 billion on Wednesday. The notes carry a total term of 30 years.

Shares Extend Their Advance

The courtroom win lent modest support to the stock. Bayer shares rose 1.3% yesterday to close at EUR 50.80, continuing a recovery that has lifted the DAX-listed group by 37% since the start of the year. In today's trading the stock changed hands at EUR 50.74, up 1.2%.

Beyond the operational pharma business, investors remain focused on the legal front in the US. Roughly two weeks ago, a hearing began in a Missouri court on approval of the Roundup settlement, with a ruling still pending after proceedings opened. The proposed deal is intended to draw a permanent line under the long-running legal uncertainty hanging over the agricultural business.