Bayer successfully defend Nexavar patent in the second instance

Generic drug manufacturers selling copycat products for Bayer's cancer drug Nexavar in Germany could now face damages claims. In a recent ruling, the German Federal Court of Justice has largely upheld an important Bayer patent and thus overturned a first-instance decision.

The dispute concerns Bayer’s patent EP 23 05 255, which expired in December 2022. The patent protects the compound of a tosylate (a type of salt) of the active ingredient sorafenib. It forms the basis of Bayer’s drug Nexavar, which is used to treat various types of cancer, including kidney, liver cell and thyroid cancer.

After the Federal Patent Court declared the patent invalid in September 2021, several generic drug manufacturers launched their products on the German market. However, following the latest decision by the Federal Court of Justice, these companies could face possible damages claims from patent holder Bayer.

Long fight

Since summer 2021, Bayer has battled to prevent the market entry of generic versions of its lucrative cancer drug. The originator drug company filed for a preliminary injunction against Zentiva, Ratiopharm (Teva), Hexal, Mylan, Betapharm, Stada and its subsidiary Aliud Pharma. The Regional Court Munich granted Bayer a temporary preliminary injunction until the end of September 2021, when the Federal Patent Court was to rule on validity.

On 29 September 2021, the Federal Patent Court handed down its ruling in a nullity suit brought by Ratiopharm and Stada. When the judges invalidated EP 255 for lack of inventive step (case ID: 3 Ni 12/20 and 3 Ni 13/21), the temporary PI expired and several generics companies launched their products.

Nevertheless, Bayer argued at the Regional Court Munich that the Federal Patent Court’s judgment in the nullity suit was wrong. The originator applied for a second PI against the generic drug manufacturers.

Damages claims could follow

In the meantime, Zentiva, Stada and Ratiopharm had filed an appeal against the first temporary PI. The appellate judges clarified that, following the German principle of separation, they would not examine inventive step. As such, they would not overrule the Federal Patent Court’s nullity decision. This decision led to Bayer withdrawing its application for the temporary as well as the second PI.

Bayer then appealed the Federal Patent Court’s nullity ruling. In its judgment a few days ago, the Federal Court of Justice upheld the patent in a slightly amended form (case ID: X ZR 83/21).

Negotiations or even disputes over damages claims for the period between the market launch of the generics and the expiry of EP 255 at the end of 2022 are now likely to follow.