SEOUL (Reuters) - A unit of healthcare conglomerate Johnson & Johnson filed a lawsuit to block a copy of its rheumatoid arthritis drug Remicade made by South Korea’s Samsung Bioepis Co Ltd from being sold in the United States.

A Johnson & Johnson building is shown in Irvine, California, U.S., January 24, 2017. REUTERS/Mike Blake

Janssen Biotech Inc, in a suit filed to the U.S. District Court of New Jersey dated Wednesday, seeks a preliminary or permanent injunction to block Samsung Bioepis’ biosimilar of Remicade from sale and argues the South Korean firm violated three of its patents.

“We have filed a lawsuit against Samsung to investigate whether their biosimilar infliximab infringes on our manufacturing process patents for Remicade,” Janssen told Reuters in a statement on Friday.

Remicade is Johnson & Johnson’s biggest selling drug, with U.S. sales of about $5 billion a year.

“We are confident we do not infringe Janssen’s patents,” Samsung Bioepis told Reuters in a statement, adding it believes Janssen is trying to delay the market entry of its Remicade copy.

“We will take all necessary measures against Janssen’s attempts to violate patient rights and deny patient access to effective, lower cost treatment options.”

Janssen’s lawsuit comes about a month after Samsung, an unlisted subsidiary of contract drug maker Samsung BioLogics Co Ltd, said it got U.S. Food and Drug Administration approval to sell its biosimilar of Remicade, which is marketed as Renflexis in the United States.

Analysts say biotech makers face increasing competition from firms such as Samsung Bioepis, which make biosimilar copies of Remicade and other drugs and sell them for cheaper. The IMS Institute for Healthcare Informatics say biosimilars could save healthcare systems in the United States and Europe’s top 5 markets as much as 98 billion euros ($108.79 billion) by 2020.

Samsung Bioepis, part of South Korea’s top conglomerate Samsung Group [SAGR.UL], develops copies of complex biotech drugs and has found early success in beating rivals to market with its versions of some of the world’s top selling drugs.

Its Remicade biosimilar is already selling in the European Union, while its biosimilar of Amgen’s rheumatoid arthritis drug Enbrel is also selling there.

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