The Australian Patent Office has recently re-affirmed in Ono Pharmaceutical Co., Ltd. et al  APO 43 that a request for a pharmaceutical patent term extension (PTE) must be based on the earliest first regulatory approval of a product falling within the scope of the claims, irrespective of whether that product is owned by the patentee or a third-party. As this consideration varies from that of other jurisdictions, it is crucial for pharmaceutical patentees in Australia to be aware of the practical implications of this decision.
The statutory framework
The Patents Act 1990 has provisions for an extension of patent term of up to five years for eligible pharmaceutical patents. The legal requirements for a pharmaceutical patent to satisfy the eligibility criteria include the following:
1. A pharmaceutical substance per se and/or a pharmaceutical substance produced by a process involving recombinant DNA technology must in substance be disclosed in the patent specification and fall within the scope of its claims.
2. The pharmaceutical substance must be included on the Australian Register of Therapeutic Goods (ARTG) before the 20-year patent term expiry.
3. The period between the effective filing date of the patent and the first regulatory approval date of the pharmaceutical substance must be at least 5 years.
The first regulatory approval date is defined as the date of commencement of the first inclusion in the ARTG of the pharmaceutical substance. A PTE application must be made during the patent term, and within 6 months of the patent grant date or commencement date of the first inclusion in the ARTG of the pharmaceutical substance, whichever is the latest.
Immune checkpoint inhibitors, such as PD-1 inhibitors, inhibit a cancer cell’s ability to evade the immune system. Australian Patent No. 2011203119 (Patent), in the name of Ono Pharmaceutical Co., Ltd. and E. R. Squibb & Sons, L.L.C. (Patentee), covers monoclonal antibodies that bind to PD-1 and discloses a method of inhibiting tumor growth in vivo using anti-PD-1 antibodies. Cancer immunotherapy drugs such as Pembrolizumab (KEYTRUDA) and the Patentee’s own Nivolumab (OPDIVO) are considered to be a significant scientific advance in developing cancer immunotherapy regimes.
KEYTRUDA and OPDIVO obtained regulatory approval in Australia on 16 April 2015 and 11 January 2016, respectively. The Patentee contended that there were two interpretations of the legislative requirements for PTE, and submitted two separate requests for PTE of their Patent. The first request was based on the regulatory approval date of KEYTRUDA and the second request on the regulatory approval date of OPDIVO.
As the OPDIVO-based PTE would provide a slightly longer extension term, the Patentee requested this request to be considered first and, if denied, the KEYTRUDA-based PTE request be considered. The Patentee had missed the deadline to file a PTE application based on KEYTRUDA, and so the KEYTRUDA-based PTE request had to be accompanied by an extension of time request.
The Delegate agreed to stay consideration of the KEYTRUDA-based PTE and the extension of time requests. The Delegate issued a deficiency notice regarding the OPDIVO-based PTE request, stating that the pharmaceutical substance of KEYTRUDA per se fell within the scope of the Patent claims and that the PTE request should have been filed within the period calculated from the date of first inclusion of KEYTRUDA on the ARTG. The Patentee requested to be heard.
This decision considered the OPDIVO-based PTE application.
Submissions and considerations
The Patentee submitted that the OPDIVO-based PTE application must be considered over the KEYTRUDA-based PTE application because “the purpose of the extension of term provisions was to restore the time lost to patentees prior to gaining marketing approval, and compensate the patentee for the additional time, expense and difficulty in developing and commercialising a “new drug”.” Furthermore, in the Patentee’s opinion, a non-liberal construction of this beneficial and remedial legislation might deem the OPDIVO-based PTE application invalid and that would be “manifestly absurd or unreasonable”.
The Delegate disagreed with the Patentee stating that “the scheme of the Act does not limit consideration to only those substances developed by the patentee and this position is not manifestly unreasonable”. The Delegate agreed that there was some level of ambiguity in the legislation as to whether the relevant pharmaceutical substance to be considered with respect to a PTE application must belong to the patentee or to a third-party.
The Delegate further referred to the finding in G.D. Searle LLC  APO 31, which had concluded that the reference to ‘earliest first regulatory approval date’ recognized that a patent might cover more than one pharmaceutical substance and a PTE request must be based on the earliest of the approval dates that apply to the patent. The Patentee challenged the correctness of this interpretation of ‘earliest first regulatory approval date’ but this was not persuasive.
It was concluded that the provisions of the PTE are to incentivize the development of ‘new’ drugs and the Patentee’s OPDIVO drug is ‘effectively the same substance’ as the third-party’s KEYTRUDA drug. In the Delegate’s opinion, allowing the OPDIVO-based PTE application would open the gates for a large number of PTE requests for ‘old drugs’, and create a situation where patentees could obtain relatively longer patent terms in comparison with the allowed statutory term for an ‘old’ drug by delaying their product inclusion on the ARTG. Therefore, the Delegate decided that the ‘earliest first regulatory approval date’ to be considered was that of the KEYTRUDA drug, which fell within the scope of the Patentee’s claims, and the Patentee’s OPDIVO-based PTE application was refused.
This decision re-affirms that a PTE for a patent claiming more than one pharmaceutical substance will be determined based on the ‘earliest first regulatory approval date’ of the substance falling within the scope of the claims, which was first registered on the ARTG, irrespective of whether the patentee owns this substance. This decision emphasizes the importance for patentees to be aware of the pharmaceutical substances, and their respective regulatory approval dates, that are within the scope of their patent claims.
Australian law differs from those of other jurisdictions in their consideration of PTE requests. It would be prudent to bear in mind that a novel and inventive, patented pharmaceutical substance can lose its ability to obtain a PTE based on its own inclusion in the ARTG, if another pharmaceutical substance considered to be ‘effectively the same substance’ and falling within the patent’s scope was included in the ARTG earlier, in which case, the PTE request will be determined based on the ARTG inclusion date of the other pharmaceutical substance, even if it is owned by a third-party.