In a judgment published on 15 September 2026 (but delivered on 27 August 2026), the Federal Court of Australia found that Pfizer had failed to establish that Samsung Bioepis’ production of Brenzys®, biosimilar to Pfizer’s Enbrel® (etanercept), infringed Pfizer’s Australian patent AU2005280034. In addition, the Judge determined that all but one of the asserted claims of the patent was invalid for lack of inventive step.
The patent at issue (which expired on 26 August 2025) related to large scale production of therapeutic polypeptides (such as etanercept) in a cell culture medium. Key to the non-infringement finding was the Judge’s view that Pfizer had failed to establish that Samsung Bioepis’ culture process resulted in cells that reached between 20% to 80% of the maximum viable cell density that would be achieved if initial growth phase culture conditions were allowed to continue, rather than being altered to a subsequent production phase (as required by the claims of the patent).
The decision comes over four years after Pfizer first filed the infringement proceedings in May 2022 against Samsung Bioepis and other respondents (including MSD, Organon and Arrow Pharmaceuticals). Those proceedings followed an action for preliminary discovery decided in 2017, which permitted Pfizer to obtain documents from the respondents in order to determine whether to commence proceedings against them for patent infringement.
It is not yet known whether Pfizer will appeal the decision.
Samsung Bioepis’ Brenzys® was the first biosimilar etanercept approved in Australia in July 2016 and was PBS listed in April 2017. Other etanercept biosimilars approved and launched in Australia are Biocon/Alphapharm’s Nepexto® (approved September 2020, PBS listed July 2025) and Sandoz’s Enbrel® (approved November 2017, PBS-listed October 2025).