The High Court of Australia will decide whether patent claims directed to a formulation are eligible for pharmaceutical patent term extension (PTE), having on 12 March 2026 granted leave to appeal the decision of the Full Federal Court in Otsuka Pharmaceutical Co Ltd v Sun Pharma ANZ Pty Ltd [2025] FCAFC 161.
Briefly, the Full Federal Court - in disagreeing with the decision of a single judge that PTE can be validly based on formulations - found that patent claims directed to formulations do not fall within the definition of “pharmaceutical substance” as required by Australia’s PTE provisions, taking the view that this term is limited to only an active pharmaceutical ingredient (API). Accordingly, Otsuka’s patent claims defining controlled release aripiprazole formulations were found ineligible for PTE and as a result, Otsuka’s product ABILIFY MAINTENA for use in the treatment of schizophrenia was only protected for the usual 20-year patent term. Our full commentary on the earlier decision of the Full Federal Court can be read here.
With all seven justices of the High Court granting leave to appeal, the apex court is expected to make a seminal ruling on what constitutes a “pharmaceutical substance”. We are set to learn whether the term covers only APIs or whether it can be extended to encompass new and advantageous formulations of known APIs, such as Otsuka’s controlled release formulation that allows monthly dosing, rather than daily.
An apparent important factor in the decision to hear the appeal is that the High Court has essentially never before considered modern PTE provisions. While PTE was central to the 2014 decision in Alphapharm Pty Ltd v H Lundbeck A-S [2014] HCA 42, that case was about whether to grant an extension of time for a late-filed PTE application. It is also noteworthy that Medicines Australia Limited, the Australian research-based pharmaceutical industry group whose members are innovator companies, and The Institute of Patent and Trade Mark Attorneys of Australia (IPTA), the representative body for Australian patent and trade mark attorneys, both made submissions to the High Court in support of the special leave application and have requested to be heard in the matter. Both groups are expected to argue for a broader meaning of “pharmaceutical substance” than asserted by the Federal Court.
We eagerly await the High Court’s decision (which is unlikely before 2027) and the resulting implications for new and existing PTEs. We will provide updates as the matter progresses. In the meantime, IP Australia has resumed considering PTE applications not impacted by the decision but has otherwise paused processing PTE applications relating to formulations. While advice from IP Australia notes that extension of time provisions can be utilised if the pause impacts an application, we are hopeful that the fee-free option open to Patent Office-caused delays will be available to clients.
