US district court sides with Sanofi, Regeneron over Amgen in ongoing PCSK9 patent dispute

The US District Court for the District of Delaware on Wednesday overturned portions of a jury verdict reached in February that upheld the validity of three of five claims asserted by Amgen on two of its US patents for the PCSK9 inhibitor Repatha (evolocumab). Karen Linehan, general counsel for Sanofi, which together with Regeneron Pharmaceuticals markets the rival PCSK9 inhibitor Praluent (alirocumab), stated "it has been our longstanding belief that all of Amgen's asserted US PCSK9 patent claims are invalid, and we are pleased today's decision reaffirms this."

Sanofi and Regeneron noted that back in February, the jury had agreed with them for two of the five asserted claims, finding they were invalid based on lack of written description. "This means that Sanofi and Regeneron have successfully invalidated all five asserted Amgen patent claims," the companies stated.  

In Wednesday's decision, Judge Richard Andrews said some patent claims by Amgen relating to antibodies targeting PCSK9 were invalid because they did not sufficiently disclose the company's purported inventions.

Meanwhile, Amgen indicated that it disagreed with certain parts of the ruling and that it would seek a review by the appellate court. "Protecting intellectual property is critical to our business since it allows for our investment in the R&D of new medicines," Amgen said, adding "we look forward to presenting our case to uphold the jury's verdict."

Amgen initially filed a patent infringement lawsuit against Sanofi and Regeneron in 2014 after the drugmakers announced plans to seek FDA approval of Praluent. The agency approved Praluent in 2015 for certain patients with high cholesterol, followed by Repatha a month later. 

In 2017, the Delaware district court issued a permanent injunction barring Sanofi and Regeneron from marketing Praluent. The injunction was suspended shortly thereafter and eventually dismissed.

Sales of Repatha reached $152 million in the second quarter, while Praluent generated €66 million ($73 million) during the three-month period.  

For related analysis, see ViewPoints: Repatha reeling after patent loss.

To read more Top Story articles, click here.