It's confirmed: Amarin loses Vascepa patent appeal, putting generics defense on life support

Amarin's blockbuster hopes for fish oil derivative Vascepa came to a crashing halt in March after a district judge struck down its key patents, just months after a major new FDA approval. Amarin put all its hopes into a successful appeal—but those chances now appear slim after another negative ruling.

The U.S. Court of Appeals for the Federal Circuit on Thursday upheld a lower court's ruling that patents protecting Amarin's purified fatty acid pill Vascepa from generic challengers were invalid based on obviousness, according to court filings. 

Amarin's share price plummeted in March on the heels of that initial ruling. The setback came as a shock, given Vascepa's blockbuster potential after an FDA label expansion in December touting its heart-helping benefits in patients with abnormally high triglyceride levels. 

The appeals hearing, which opened Wednesday, immediately appeared to swing against Amarin, given the selection of three judges analysts believed would pose a roadblock to a successful challenge.

SVB Leerink analysts forecast to clients in a Wednesday note that two of the judges wouldn't "be in the upper half of the 12 possible active judges most likely to side with Amarin." Cantor analyst Louis Chen—a notable bull for Vascepa's appeals chances—called the panel's composition a "net neutral" for Amarin. 

In a statement, Amarin said it was looking over its legal options and planned to file for an "en banc" session before a 12-judge appeals panel within 30 days. The drugmaker expects to continue promotional efforts for Vascepa and is seeking additional global regulatory approvals. 

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Amarin's loss will open the door for three challengers in the initial patent suit to launch their generic versions of Vascepa immediately.

One of those copycats, a version from Hikma Pharmaceuticals, notched an FDA approval in May, setting the generics maker up to launch at risk as Amarin's appeal made its way through court.

Amarin struck a deal in June with Apotex, one of the generics companies not party to the patent case, to put off its Vascepa generic until 2029 if Amarin won its appeal.

RELATED: Amarin spurns would-be marketing partners to launch Vascepa in Europe on its own

Without its U.S. patents, Amarin would be forced to lean on sales abroad, particularly in Europe where the company is still awaiting regulatory approval.

In August, Amarin announced it would launch Vascepa in Europe without more established marketing partners, despite receiving multiple proposals. Amarin expects an EU regulatory decision in early 2021 and has already hired a commercial head, Karim Mikhail, who joined from his own commercial consultancy founded in 2018.

Amarin plans to hire a core commercial team of around 12 this year and then add country-by-country sales teams as it builds out approvals and reimbursement. Its initial focus would be on larger EU countries, President and CEO John Thero said in an earnings call with investors at the time.