Amgen and its PCSK9 rivals Sanofi and Regeneron have been battling over U.S. patents for years, but this week Amgen scored a win in Germany—and it's the sort of win the company would like to duplicate in the U.S.

A German court in Düsseldorf ruled Sanofi and Regeneron’s Praluent infringes an Amgen patent and granted Amgen's request for an injunction to push its rivals' drug off the market. Now, Amgen can post a bond for the injunction to go into effect.

In a statement, Amgen said it intends to enforce the decision and is "committed to facilitating a smooth transition to Repatha." The company is prioritizing "continuous care" for patients and isn’t immediately seeking removal of Praluent stock in hospitals and pharmacies.

Sanofi and Regeneron said they’re disappointed and "continue to believe that patients and physicians should have a choice of cholesterol-lowering therapies in order to achieve optimal lipid-lowering for patients." The partners said they believe the "law and facts support our positions."

The loss comes amid a yearslong patent battle in the U.S. Amgen initially scored an injunction way back in 2016, and the following year an appeals court tossed the ban. More recently, in February, Amgen convinced a jury in California its patents are valid. Sanofi and Regeneron argue Amgen has "overly broad" patent claims.

Afterward, Sanofi and Regeneron said they planned to pursue every legal avenue to invalidate the Amgen patents, starting with a motion to overturn the jury verdict. 

Hundreds of millions of dollars are at stake. Repatha sales last year reached $358 million in the U.S. and $192 million in the rest of the world. Praluent hasn’t been as successful commercially, growing to €261 million ($293 million) in global sales last year.

The companies launched their PCSK9 cholesterol drugs back in 2015 to great fanfare, but the meds never lived up to early commercial expectations. Payers clamped down on access due to list prices of around $14,000 per year. This year, the companies cut their prices dramatically in a bid to bolster access.