• Amgen plans to enforce a court-granted injunction prohibiting sales in Germany of Sanofi and Regeneron’s cholesterol drug Praluent, which competes with Amgen’s rival Repatha. 
• The Dusseldorf Regional Court on July 11 ruled in favor of Amgen, finding Praluent infringed on an Amgen patent covering antibodies which bind to PCSK9, a protein that’s targeted by both Praluent and Repatha to lower LDL cholesterol for certain patients.
• Amgen and partners Sanofi and Regeneron are locked in litigation in the more valuable U.S. market as well. In February, a federal jury upheld the validity of two patents held by Amgen and the companies await a decision from an injunction hearing held in Delaware court in June.

The court battle between Amgen and Sanofi and Regeneron predates the U.S. approval of both Repatha (evolocumab) and Praluent (alirocumab) in 2015. 

But, as the German court decision signals, the effects of the long-running legal battle could start to become apparent. 

Neither drug has enjoyed strong commercial success, but Repatha has outperformed Praluent in recent quarters. Sales of Praluent totaled $41 million outside of the U.S., although it’s not clear how much of that came from the German market.

Both Amgen and the team of Sanofi and Regeneron have reduced the price of their respective drugs in the U.S. in a bid to lift sluggish sales.

Praluent currently remains on the market in Germany, according to a statement from Regeneron, which noted Amgen needs to post a bond for an injunction to go into effect. 

For its part, Amgen said it would work to ensure a smooth transition to Repatha for patients currently taking Praluent, and that it would not seek to remove existing stocks of Praluent at pharmacies and hospitals. 

“We are disappointed in this decision, 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,” Regeneron said in a statement. 

While the market for PCSK9 inhibitors only just crossed $1 billion in annualized sales, Wall Street analysts still see potential for multi-billion dollar product sales over time. Currently, Repatha and Praluent are the only two PCSK9-blocking drugs available, although The Medicines Company hopes to win a U.S. approval for its experimental medicine inclisiran. 

An injunction against Praluent might also be a possibility in the U.S, where Amgen has won a federal jury verdict. Sanofi and Regeneron plan to seek a new trial, however, potentially extending the legal fight.