Regeneron-Sanofi Get Favorable Ruling Against Amgen in Court

Regeneron Pharmaceuticals, Inc. REGN and partner Sanofi SNY announced that the U.S. District Court for the District of Delaware ruled in their favor in the ongoing litigation for PCSK9 inhibitor Praluent’s (alirocumab) patent against rival Amgen, Inc. AMGN, which sells its own PCSK9 inhibitor, Repatha.

The court determined that Amgen's asserted patent claims for antibodies targeting PCSK9 (proprotein convertase subtilisin/kexin type 9) are invalid based on lack of enablement.

The latest ruling overturned portions of an earlier jury verdict upholding the validity of three claims. In February 2019, a jury determined that two other asserted Amgen patent claims are invalid. As a result, Regeneron and Sanofi have successfully invalidated all five asserted Amgen patent claims. 

Both companies have been involved in a longstanding duel regarding Praluent and Repatha, whereby Amgen is trying to prevent the manufacture, use and sale of Praluent claiming infringement of patents.

Nevertheless, the latest ruling bodes well for Regeneron and Sanofi. Regeneron’s shares have lost 23% in the year so far compared with the industry’s  decline of 2.4%.


We note that both Praluent and Repatha inhibit the protein known as PCSK9, which lowers the liver's ability to remove "bad" cholesterol (LDL-C) from the blood. Praluent was developed by Regeneron and Sanofi under a global collaboration agreement and invented by the former using its proprietary VelocImmune technology. Though both drugs were approved in 2015, the uptake has been disappointing as these are expensive. The companies have been striving hard to capture market share and secure deals with health insurers and pharmacy benefit managers.

Amgen's Repatha has captured a significant market share in certain jurisdictions. Repatha also received regulatory approval for cardiovascular risk reduction before Praluent in certain jurisdictions, including the United States. In a bid to improve access, Sanofi and Regeneron announced a 60% cut in the U.S. list price of Praluent earlier this year. Last year, Amgen too had taken similar action.

Zacks Rank & A Stock to Consider

Regeneron currently carries a Zacks Rank #3 (Hold).

A better-ranked stock in the biotech space is Alexion Pharmaceuticals, Inc. ALXN, which carries a Zacks Rank #2 (Buy). You can see the complete list of today’s Zacks #1 Rank (Strong Buy) stocks here.

Alexion’s earnings estimates have been revised 4.2% upward for 2019 and 2.1% for 2020 over the past 60 days.

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