The US District Court for the District of New Jersey has upheld two of Amgen’s patents for its top-selling drug Enbrel (etanercept) in a ruling against Sandoz, which has been seeking to launch its copycat version Erelzi.

First developed by Immunex, which Amgen acquired in 2002, Enbrel is a tumor necrosis factor (TNF) blocker for treating autoimmune diseases such as rheumatoid arthritis, plaque psoriasis, psoriatic arthritis, ankylosing spondylitis and polyarticular juvenile idiopathic arthritis. The drug, which has been available since 1998, achieved sales of $4.8 billion in 2018.

According to Reuters news agency, US District Judge Claire Cecchi dismissed comments from Sandoz that Enbrel’s active ingredient patents — which expire in 2029 — should not have been granted because the ingredients exist in other patents.

Commenting on the court’s decision, Amgen’s chairman and CEO Robert Bradway, said: “We are pleased with today's decision recognizing the validity of these patents.  Protecting intellectual property is critical to incentivize innovation and the large investments in research and development that are required to bring new medicines to patients and fully develop their therapeutic potential for patients.”

Sandoz said it will appeal. “Sandoz respectfully disagrees with the court’s ruling, which prevents us from launching an additional treatment option for patients with autoimmune and inflammatory diseases,” said Carol Lynch, president and head of Sandoz’s North American division. “We will appeal this decision, and look forward to presenting our case to the Federal Circuit and bringing Erelzi to US patients as soon as possible.”

Elrezi was the first biosimilar etanercept to get approval from the US Food and Drug Administration (FDA). However, since that approval in August 2016, Sandoz said it has not been able to launch its biosimilar version due to the legal proceedings with Amgen.

Amgen also filed another complaint in May 2019 in the District Court of New Jersey against Samsung Bioepis relating to the South Korean group’s Enbrel biosimilar, called Eticovo. The lawsuit alleges infringement of five Enbrel patents.