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(Reuters) - A U.S. judge on Wednesday set aside a jury verdict that found Amgen Inc patents on its cholesterol drug Repatha were valid, handing a victory to Regeneron Pharmaceuticals Inc and Sanofi SA, which sells a rival drug.

The ruling from U.S. District Judge Richard Andrews in Wilmington, Delaware was the latest reversal of fortune in a long-running lawsuit in which Amgen is seeking to stop French drugmaker Sanofi and U.S. biotech Regeneron from selling their drug Praluent.

Repatha and Praluent won U.S. approval about two weeks apart in July of 2016. Both drugs dramatically lower “bad” LDL cholesterol by blocking a protein known as PCSK9 that prevents LDL removal from the blood. The injected drugs were later shown to also cut the risk of heart attacks.

The judge, in setting aside the jury’s verdict reached in February, said some patent claims by Amgen relating to antibodies targeting PCSK9 were invalid because they did not sufficiently disclose the Thousand Oaks, California-based company’s claimed innovations.

“It has been our longstanding belief that all of Amgen’s asserted U.S. PCSK9 patent claims are invalid, and we are pleased that today’s decision reaffirms this,” Sanofi and Regeneron said in a statement.

California-based Amgen said in a statement that it disagreed with aspects of the court’s decision and will seek review by the appellate court.

“Protecting intellectual property is critical to our business since it allows for our investment in the research and development of new medicines,” Amgen said. “Consequently, we are disappointed with today’s decision, and we look forward to presenting our case to uphold the jury’s verdict.”

Despite initial forecasts for multibillion-dollar sales, restrictions placed by insurers on use of the potent but expensive drugs have severely limited patient access and sales.

Repatha had worldwide sales of $152 million in the second quarter of 2019, while Regeneron reported Praluent sales of $73.7 million for the period.