Securing a series of wins in a patent dispute involving the rare disease treatment Soliris®

On behalf of Samsung Bioepis, Lee & Ko’s Intellectual Property Practice Group prevailed in patent invalidation and infringement actions relating to Soliris®, paroxysmal nocturnal hemoglobinuria treatment, thereby enabling Samsung Bioepis to launch its biosimilar on an earlier schedule.

Soliris® is a rare disease treatment developed by Alexion Pharmaceuticals (“Alexion”), a U.S. pharmaceutical company, and is an extremely expensive drug with annual costs borne by each patient reaching KRW 500 million (approx. USD 363,100).  Alexion, the patentee, held two registered patents for Soliris®, of which the composition patent expired in 2015, with only the use patent remaining at the time of the suit.  Last June, Samsung Bioepis preemptively filed an invalidation action against the use patent, and in response, Alexion filed a patent infringement suit against Samsung Bioepis.

Lee & Ko argued that the priority claim of the asserted patent should be denied and that there was a lack of novelty and inventive step.  The Intellectual Property Trial and Appeal Board (the “IPTAB”) agreed and invalidated Alexion’s patent.  Alexion appealed the decision to the IP High Court, which affirmed the IPTAB’s decision, again siding with Lee & Ko’s arguments.  With Alexis deciding not to file an appeal with the Supreme Court, the determination on the patent invalidity became final and conclusive.  Samsung Bioepis also won in the patent infringement suit on the ground that the filing of the suit amounted to an abuse of patent rights based on an invalid patent.

Based on these wins, Samsung Bioepis obtained market approval for Epysqli®, a biosimilar of Soliris®, from the Ministry of Food and Drug Safety in January 2024 and successfully launched the product in Korea in April.