A German court has dealt the first blow against CureVac amid the company's heated COVID-19 vaccine patent fight with fellow German mRNA specialist BioNTech.

The German Federal Patent Court ruled that one of eight CureVac patents involved in the litigation is invalid, the company said in a Tuesday release. The patent in question covers a process that improves the expression of mRNA in cells, Juve Patent reports.
The ruling came as a surprise to CureVac, which noted that the court in April issued a preliminary opinion in favor of the patent's validity.
Still, CureVac believes its "pioneering role in mRNA technology and continuing innovation in the field made essential contributions to safe and efficacious COVID-19 vaccines,” CEO Dr. Alexander Zehnder said in a statement.
The company will "continue to defend our claim for recognition and fair compensation and will take appropriate action by appealing this decision," Zehnder added.
CureVac’s appeal will be with the German Federal Court of Justice.
Meanwhile, CureVac is pressing its claims on seven other patent rights. In September, the Regional Court Düsseldorf moved to suspend action on four of CureVac’s patents involved in the lawsuit, a decision that CureVac believed played in its favor.
But investors didn't welcome that news, as CureVac's shares fell around 10% at the time.
The new ruling “sets the tone” for other decisions as the case was the first filed and is the furthest along, Evercore ISI analysts wrote in a note to clients. In addition, the analysts found this particular patent to be among the strongest involved in CureVac’s litigation.
After the latest patent invalidation, CureVac's shares were trading 26% lower on Tuesday.