Following on from our earlier article on patent term extension (PTE) for pharmaceutical substances, three related decisions issued by the Australian Patent Office provide guidance on the requirements and potential pitfalls when seeking an extension of term.

Criteria for eligibility and necessary document

As noted in our previous article, as set out by section 70 of the Patents Act 1990, a patent is eligible for PTE i) where the claims of the patent encompass:

  1. Pharmaceutical substance(s) per se; or
  2. Pharmaceutical substance(s) produced by recombinant DNA technology

and ii) where that pharmaceutical substance is included in goods which have received regulatory approval at least five years following the effective date of the patent.  The PTE application must be made in the "prescribed manner" which includes providing evidence to show that the goods containing the substance are currently included in the Australian Register of Therapeutic Goods (ARTG) and being made within six months of the earliest inclusion of the pharmaceutical substance in the ARTG, or grant of the patent whichever is later.

Background to Decisions

The three PTE applications were made by iCeutica Pty Ltd for the Australian Patents 2014208310, 2013273795 and 2010239080 in relation to the product Zorvolex®.  Zorvolex® contains the substance diclofenac (2-(2,6-dichloroanilino)phenylacetic acid) and is used as an anti-inflammatory and analgesic.  The applications in question all rely on similar subject matter in relation to pharmaceutical compositions of diclofenac as nanoparticles formed by the process of dry milling diclofenac, with a surface stabiliser and grinding compound.  Each case is discussed briefly below.

Case #1:  iCeutica Pty Ltd [2018] APO 77 – Not the first inclusion to the ARTG

Following the PTE application for Australian Patent No. 2013273795, a deficiency notice was issued outlining two grounds for refusal.  The first ground for refusal considered that the pharmaceutical substance per se did not 'in substance' fall within the scope of the claims.  The second ground for refusal was on the basis that the PTE application was not timely filed.  The Deputy Commissioner considered that the matter could be decided on this ground and that it was not necessary to consider the first ground. However, he did provide commentary.

The definition of a pharmaceutical substance in the Act is as follows:

"a substance (including a mixture or compound of substances) for therapeutic use whose application (or one of whose applications) involves:

a) a chemical interaction, or physico-chemical interaction, with a human physiological system; or

b) action on an infectious agent, or on a toxin or other poison, in a human body;

but does not include a substance that is solely for use in in vitro diagnosis or in vitro testing."

The Examiner of the PTE application alleged that claims encompassing a "mixture of substances", which included (i) nanoparticle of diclofenac, ii) lactose monohydrate and iii) sodium lauryl sulfate, were not considered to be for a "pharmaceutical substance" per se as the latter two integers ii) and iii) were considered to be by-products of the dry milling process and "separate physical integers" not directly involved in a physico-chemical interaction within the human body.

However, consistent with a number of earlier decisions to which the Deputy Commissioner referred, he found that the mixture of a surface stabiliser, nanoparticle of diclofenac and millable grinding compound should be considered a pharmaceutical substance per se, even though not all components are achieving a "physico-chemical interaction in the human body".

The second ground for refusal alleged that the application was not made within 6 months of the first inclusion of the goods in the ARTG.  The second ground for refusal was based on section 71(2)(b) of the Act, which states:

"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 subsection 70(3)..."

While the product Zorvolex® (containing the active ingredient diclofenac) was included in the ARTG, the Deputy Commissioner disputed that it was the earliest first inclusion of a pharmaceutical substance encompassed by the claims in the ARTG.  Relevantly, claim 16 of Australian Patent No. 2013273795 recites:

"A nanoparticle composition comprising a surface stabiliser and nanoparticles of a solid biological active compound selected from the group consisting of: diclofenac, olanzapine, raloxifene and fenofibrate; dispersed in a millable grinding compound selected from the group consisting of:  NaCl and lactose."

The Deputy Commissioner noted that Lipidil® was included in the ARTG 10 years prior to Zorvolex® and contains fenofibrate and additives including sodium lauryl sulfate and lactose monohydrate.  As such, Lipidil® was considered in substance to fall within the scope of claim 16 and was considered to be the earliest inclusion in the register of goods containing a pharmaceutical substance falling within the scope of the claims.  Thus, the PTE application was refused.

While the patentee directed the Deputy Commissioner's attention to claim 27 which only recites the biological active compound of diclofenac, the Deputy Commissioner held that the Act "does not allow a patentee to select a claim" in this fashion, as this would allow a patentee to simply use the most recent ARTG registration as a strategy to extend the term of a patent covering various other pharmaceutical substances.

The case highlights that patentees must be aware that the earliest "first inclusion in the ARTG" extends to any pharmaceutical substance that falls within the scope of the patent claims.  Therefore, where patent claims encompass multiple "pharmaceutical substances", an earlier approval for goods containing one of those substances can lead to an inability to gain a PTE on the basis of a later approval involving a different substance or indeed the same substance.  In cases where the scope of the claim may encompass goods having an earlier approval date, a patentee may elect to amend the claims to be focused to the goods being relied on for PTE, however such amendments should be timely filed in view of the deadline for filing the PTE application.

Case #2:  iCeutica Pty Ltd [2018] APO 78 – Requirements for evidence

In this case, the first ground for refusal of PTE for Australian Patent No. 2010239080 was similarly based on the pharmaceutical substance per se not "in substance" falling within the scope of the claims.  Similar to the previous case, the Deputy Commissioner was satisfied that the pharmaceutical composition comprises a pharmaceutical substance.

The second ground of refusal alleged that there was insufficient evidence to show that Zorvolex® possessed the necessary dissolution as recited in the granted claims.  In particular, [claim 1 recites a dissolution rate of diclofenac acid such that at least 91% by weight, is released by 45 minutes].

Despite opportunity, the patentee provided only "a hearsay statement, which was not in declaratory form" that Zorvolex® has the requisite dissolution profile. As such, the Deputy Commissioner was not convinced (to the requisite level, i.e. on the balance of probabilities) that Zorvolex® has the dissolution profile recited by claim 1.  Thus, the application for PTE was refused.

The Deputy Commissioner's position was based on regulation 6.8 which states:

"(2) For paragraph 71(1)(c) of the Act, the application must be accompanied by information showing that goods containing, or consisting of, the substance are currently included in Australian Register of Therapeutic Goods.

(3) The application must also be accompanied by information identifying the substance, as it occurs in those goods, in the same way (as far as possible) as the substance is identified in the complete specification of the patent."

In many instances an Applicant may elect to narrow their claims during prosecution by including "technical features" provided by the invention.  However, if an application for PTE is made, there must be evidence to show that the goods in the ARTG possess such "technical features", in order to be eligible for extension of term.

Case #3:  iCeutica Pty Ltd [2018] APO 76 – Specific dosage range and size requirements

In the final case, the first intention to refuse the PTE for Australian Patent No. 2014208310 was again based on the ground that the pharmaceutical substance per se does not in substance fall within the scope of the claims.  In the present case, however, the claims were directed to a specific amount of diclofenac and with a specific particle size, raising questions as to the role of such features when considering a pharmaceutical substance per se.  Claim 1 of the patent reads:

'A unit dosage form of a pharmaceutical composition containing 18mg or 35mg of diclofenac, wherein the median particle size of the diclofenac determined on a particle volume basis, or the average particle size determined on a particle number basis, is less than or equal to 5000 nm.'

The Deputy Commissioner considered that the physico-chemical interaction is caused by diclofenac in conjunction with its particle size and that the quantity specificed is not merely a convenient selection but is selected so as to achieve the physico-chemical interaction. He was therefore satisfied that the unit dosage form was a pharmaceutical substance per se. It was further found that the quantity of diclofenac in Zorvolex®'s product description is limited to either 18 or 35mg, that the median particle size was 200-800nm and that the goods in the ARTG contained or consisted of the pharmaceutical psubstance which was in substance disclosed and falling within the scope of the claims. Consequently, the PTE application in this case was successful.

Conclusions:

  • These cases confirm that pharmaceutical compositions comprising an active ingredient and other components (excipients), which themselves do not provide a physico-chemical interaction within the human body, can be eligible for PTE.
  • An application for PTE must be based on the broadest reading of the claim set as a whole. This should be borne in mind when considering divisional applications.  The claims of the patent to be extended which cover more than one active ingredient should also be cross-checked against any goods entered into the ARTG to determine what registered goods are encompassed by the claims.
  • Evidence may be required to show that any necessary technical features included in a claim are evident in the goods entered in the ARTG.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.