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In Australia, there have been several recent court and Patent Office decisions in which previously granted patent extensions of term were reduced by the court and the commissioner of patents in light of information brought to their attention. Moreover, these decisions have provided interpretation of aspects of Sections 70, 71, and 77 of the Patents Act 1990 relating to extensions of term of pharmaceutical patents.

Summary

When considering a patent extension of term application under Section 70, the first inclusion on the Australian Register of Therapeutic Goods (ARTG) includes both listed goods without marketing approval and registered goods. In respect of the timing of an application under Section 71, the application must be filed within six months of the first inclusion on the ARTG of goods that contain any of the substances which fall within the scope of the claims, including those listed by third-party sponsors. In calculating the length of the extension of term under Section 77, it is based on the earliest first regulatory approval date in relation to any of the substances which are disclosed in the complete specification and which fall within the scope of the claims, not necessarily the substance for which the extension is being sought. This has implications for patentees which list a substance on the ARTG and later find a different substance within the scope of their claims that is far more commercially valuable, as the date of the earlier inclusion will limit any extension for the superior compound. Bearing in mind the timing limitations, perhaps one way to avoid loss of extension of term under these circumstances would be to file divisional applications directed to specific compounds in order that they are not affected by the listing of other compounds disclosed in the specification. There now appears to be an obligation on the patentee to amend the extension of term application if they later become aware of relevant substances with an earlier first regulatory approval date. However, the Patent Office decisions have not been tested in court.

Recent decisions

Section 70 sets out the requirements in order to apply for an extension of term, including: 

  • goods containing, or consisting of, the substance must be included in the Australian Register of Therapeutic Goods; and 
  • the period beginning on the date of the patent and ending on the first regulatory approval date for the substance must be at least five years.

The decision of the Federal Court in Pfizer Corp v Commission of Patents ([2006] FCA 1176) and subsequently upheld by the Full Court of the Federal Court ([2006] FCAFC 190) provided guidance as to the scope of the “first regulatory approval date”. Four Pfizer patents had had their term extended by the commissioner of patents. However, on 23rd September 2005 the commissioner directed amendments to the Register of Patents to shorten the terms of the patents.

Regulation 6.9(2) of the Patents Regulations provides that an application for an extension must be accompanied by a certificate (or other information in the absence of a certificate) stating the date of commencement of the first inclusion in the ARTG that contain, or consist of, the substance. The extensions had been granted on the basis of when the pharmaceutical substances were included as registered goods. However, the pharmaceutical substances had previously been entered as listed goods.

The court held that, in respect of Section 70, the first inclusion on the ARTG includes listed goods without marketing approval. According to the court, the patentee has a choice as to which regulatory approval to obtain to enable it to exploit the patented pharmaceutical substance. Subject to the requirements of the Therapeutic Goods Act, the two options of inclusion in the ARTG as listed goods or inclusion in the ARTG as registered goods are both available to a patentee. Thus, the commissioner reduced the patent term extension in respect of the Pfizer patents to reflect extensions based on when the goods were first listed on the ARTG.

Section 71 (2) of the Patents Act relates to the timing of an application for a patent extension of term:

"An application for an extension of the term…. must be made… within six months after the latest of:

(a) the date the patent was granted; (b) the date of commencement of the first inclusion in the Australian Register of Therapeutic Goods of goods that contain, or consist of, any of the pharmaceutical substances referred to in Section 70(3); (c) the date of commencement of this section."

In re G D Searle LLC ([2008] APO 31(5th December 2008)) the Patent Office held that the timing of an application for a patent extension of term in relation to Section 71 (2)(b) of the act is not limited to the date of commencement of the first inclusion in the ARTG of goods of the patentee.

Searle filed an application for extension of term of Patent 680635 under Section 70, based on the substance darunavir. However, there was another substance (amprenavir) within the scope of the claims that had been included in the ARTG six years earlier and, as a consequence, the application for an extension of term was not made within six months of the commencement of the first inclusion in the ARTG of goods that contain a relevant pharmaceutical substance. Neither of these goods was sponsored by Searle.

At a subsequent hearing the delegate upheld the examiner’s opinion and, in reaching his decision, referred to Justice Bennett’s statement in Pfizer Corp in relation to Section 77 that:

Section 77 refers to the earliest first regulatory approval date. This recognizes that the patent may cover more than one pharmaceutical substance and provides the term of the extension is based on the earliest of the approval dates that apply to the patent.

According to the delegate, the act does not intend an application for extension to be made on the basis of one inclusion and the term of the extension calculated on the basis of another. As the application was found not to comply with Section 71, the application could not be accepted. The delegate decided to allow the patentee to make a new application based on amprenavir or any other earlier inclusion accompanied by an application for an extension of time under Section 223.

When a patentee files an application for an extension of term, they are not obliged to search the ARTG for all possible pharmaceutical substances covered by their patent and all possible first regulatory approvals, but can rely on the regulatory approvals of which they are aware. However, once aware that there is an earlier first regulatory approval, they have no option but to amend the application and, if necessary, make a request under Section 223.

Under Section 77 of the act the term of the extension of term is equal to the period beginning on the date of the patent and ending on the earliest first regulatory approval date (as defined by Section 70) in relation to any of the pharmaceutical substances referred to in Section 70(2), reduced (but not below zero) by five years.

In Pfizer Italia Srl ([2007] APO 2 (12th January 2007)) the Patent Office provided guidance on the meaning of “the earliest first regulatory approval date in relation to any of the pharmaceutical substances referred to in Section 70(2)”.

The patentee was granted an extension of term for Zavedos (idarubicin hydrochloride), which was subject to an ARTG registration on 19th August 1999. Later, solicitors for Pfizer Italia advised the commissioner of patents that Pfizer marketed a number of products, containing active ingredients other than idarubicin, which fell within the scope of the claims of the patent and each having an earlier first regulatory approval date. Pfizer attempted to argue that “the earliest first inclusion” in the ARTG must be read as a reference to the first entry in the ARTG in respect of any presentation of a therapeutic good that contains the pharmaceutical substance in question (idarubicin), as the substance can be entered a number of times in different formulations as distinct goods.

The delegate disagreed and held that the definition in Section 70(5) is given in relation to the substance and not the goods that contain it, and therefore each pharmaceutical substance can have only one first regulatory approval date. Moreover, Section 70(3)(b) refers to the regulatory approval date for the substance. Accordingly, a patent may disclose and include within the scope of its claims more than one pharmaceutical substance and, under Section 70(5), each pharmaceutical substance has only one first regulatory approval date. Therefore, the only reasonable interpretation of Section 77(1) is that it is intended that the term of the extension must be based on the earliest of the approval dates that may apply to the patent. Therefore, the term of the extension granted to Pfizer should have been zero and the term of the patent expired on 19th June 2006.

In Australia, the term of extension is not limited to a particular pharmaceutical substance per se, but applies to the entire patent for up to five years. Exploitation of a patent for a pharmaceutical substance or substances can commence when any part achieves regulatory approval.

Assuming the interpretations of the extension of term provisions behind these decisions are robust, pharmaceutical companies seeking an extension will now have to carefully manage the process of regulatory approval where several compounds fall within the scope of their patent claims, and be pro-active regarding infringing compounds listed by third-party sponsors.