Freeze dried generics frozen in their extended tracks

Freeze dried generics frozen in their extended tracks

Freeze dried generics frozen in their extended tracks

Pharmacia Italia S.p.A v Mayne Pharma Pty Ltd and
Pharmacia Italia S.p.A. v Interpharma Pty Ltd [2006] FCA 305 (29 March 2006, Weinberg J)

In February 2006 in an article titled “Freeze-dried generics frozen in their tracks”, we reported on two separate Federal Court decisions relating to a patent owned by Pharmacia Italia S.p.A. (Pharmacia). In those decisions, the court found infringement by Mayne Pharma Pty Ltd (Mayne) and granted an injunction against Interpharma Pty Ltd (Interpharma).

The parties were recently back in the Federal Court arguing over the effect of an extension of term to the patent. The primary issue in both proceedings was whether the Patent, and claim 1 in particular, claimed a ‘pharmaceutical substance per se’ and was therefore eligible for an extension under section 70 of the Patents Act 1990.

The Court found that claim 1 did disclose a pharmaceutical substance per se even though the claim included process elements. The Court held that the references to the various process components were not to be regarded as seeking to protect ‘process’. They simply marked out the basis upon which the new and inventive substance can be distinguished from other prior art, and enable the scope of the protection to be more accurately understood. The decision shows that claims including process elements may nevertheless be eligible for extension of term under Australian law.

Claim 1

Claim 1 states as follows.

A sterile, pyrogen-free, anthracycline glycoside solution which comprises a physiologically acceptable salt of an anthracycline glycoside dissolved in a physiologically acceptable aqueous solvent therefore at an anthracycline glycoside concentration of from 0.1 to 50 mg/ml, which has not been reconstituted from a lyophilisate and the pH of which has been adjusted [to] from 2.5 to 5.0 solely with a physiologically acceptable acid.

Pharmaceutical substance per se – the parties’ arguments

Mayne submitted that claim 1 contained the following process components, and therefore was not a claim to a pharmaceutical substance per se:

  1. the product of claim 1 must be made by a process other than by reconstitution from a lyophilisate (in a vial immediately prior to administration);
  2. the salt of the active ingredient must have been dissolved in an aqueous solvent;
  3. the product must be made by a process of adjustment of the pH into a range of between 2.5 and 5.0; and
  4. that adjustment must solely have been done with a physiologically acceptable acid.

According to Mayne, it was not any anthracycline glycoside solution that would infringe claim 1, but only a solution obtained in accordance with the process integers of that claim. Interpharma’s arguments largely mirrored those made by Mayne. However, in one respect they went further and we discuss this below.

Pharmacia submitted that claim 1 was a claim in relation to a pharmaceutical substance per se. In simple terms, it argued that the injectable ready-to-use solution was a mixture of substances which had particular characteristics, enabling the substance to be readily defined, and differentiated from other pharmaceutical substances that were not within the protection of the Patent.

Pharmaceutical substance per se – the Court’s conclusion

Weinberg J analysed the decisions of the Full Court and Heerey J at first instance in Boehringer Ingelheim International GmbH v Commissioner of Patents (Boehringer), including Heerey J’s analysis of the history behind the current mechanism for extending the term of pharmaceutical patents, which led Heerey J to make the following comments:

Broadly speaking, a claim in relation to a pharmaceutical substance can be made in three ways:
(i) a new and inventive product alone;
(ii) an old or known product prepared by a new and inventive process;
(iii) an old or known product used in a new and inventive mode of treatment.

What is clear in Section 70 is that only the first type of claim to a pharmaceutical product is to be subject to extension rights.

According to Weinberg J the question came down to:

Is claim 1, when read sensibly, and as a whole, properly to be understood as a claim to a new and inventive substance, or are the various references to process elements in that claim, upon which Mayne relied, sufficient to take it outside the ambit of a ‘pharmaceutical substance per se’?

The matter must largely be one of impression, and degree. Reasonable minds may differ as to whether the legitimate boundaries of a ‘pharmaceutical substance per se’ have been crossed.

His Honour concluded that when claim 1 is read fairly, and not perversely, and when it is read as a whole, it states a claim to a new and inventive substance, and not to a novel process or method. The references to the various process components (listed above), when understood in context, are not to be regarded as seeking to protect ‘process’. They simply mark out the basis upon which the new and inventive substance can be distinguished from other prior art, and enable the scope of the protection to be more accurately understood.

In particular, Weinberg J held that:

  1. the reference to a ‘sterile, pyrogen-free, anthracycline glycoside solution’ was nothing more than a description of the broad characteristics of the solution in question;
  2. the use of the verb ‘dissolved’ did not, in context, describe a process that is said to be new and inventive, but merely links the therapeutically significant substance (or active ingredient) with the solvent which, when taken together, go to make up the overall product; and
  3. the further references in claim 1 to the concentration to be achieved, the fact that the substance has not been reconstituted from a lyophilisate, and the fact that the pH has been adjusted solely with a physiologically acceptable acid, though certainly having elements of process about them, are not, when understood in context, to be regarded as seeking to protect ‘process’. They simply mark out the basis upon which the new and inventive substance can be distinguished from other prior art, and enable the scope of the protection to be more accurately understood.

Weinberg J further held that when construing a claim, in order to determine whether the requirements set out in paragraph 70(2)(a) are satisfied, it is appropriate to have regard to the reason why any reference to process has been included in the claim as formulated. There is a difference between seeking to protect a process (which can be the subject of a patent, but cannot be the subject of an extension), and merely referring incidentally to some elements of process, that are not themselves novel, in order to better describe the new and inventive substance.

Importantly His Honour concluded that the approach argued by Mayne and Interpharma would deprive the section of much of its force. It would deny a patentee of a pharmaceutical substance the right to have the protection afforded by its patent extended, in the face of sound economic and policy reasons embodied in the legislation as to why, in the limited cases therein set out, such extension ought to be possible.

Pharmaceutical substance – Interpharma’s additional argument

Interpharma seems to have argued that claim 1 did not define a ‘pharmaceutical substance’ let alone a ‘pharmaceutical substance per se’. Interpharma called as an expert witness Dr Geraldine Anne Elliott, Director of Research and Development of Imaginot Pty Ltd, a company engaged in the development of orally administered drug delivery systems. Dr Elliott had a PhD and an MBA, was a registered pharmacist and had previously been responsible for Mayne’s injectable product development program which included a number of projects on anthracycline glycosides. Those projects involved the development of stable formulations of lyophilisates.

Dr Elliott considered that the ‘physiologically acceptable salt of an anthracycline glycoside’ described in claim 1 was a pharmaceutical substance as this was the compound that exerts a therapeutic effect in the body, in this case a cytotoxic effect against cancer cells. However, neither the ‘physiologically acceptable aqueous solvent’ nor the ‘physiologically acceptable acid’ for pH adjustment had any cytotoxic pharmacological action. They were pharmacologically inert ingredients in the solution, necessary to stabilise the product, and prevent degradation of the anthracycline glycoside, but were not themselves ‘pharmaceutical substances’.

Mayne expressly declined to adopt Interpharma’s submission that Pharmacia’s product was not, relevantly, a ‘pharmaceutical substance’. Mayne confined its submission to contending that the product was not a ‘pharmaceutical substance per se’, essentially because it encompassed elements of process.

Pharmacia’s counsel cross-examined Dr Elliot at length on this issue and pointed out that the Patent Office Manual of Practice and Procedure (which Heerey J had referred to in Boehringer) stated:

In the case of such mixtures or compounds the test of whether or not a substance is a pharmaceutical substance applies to the mixture or compound as a whole, not to an individual component of the mixture or compound.

When Dr Elliott’s attention was drawn to what the Manual said about the meaning of ‘pharmaceutical substance’, and what both Heerey J and the Full Court had said about that matter in Boehringer, she remained ‘doggedly of the view that her position was correct, and what was said elsewhere was of little consequence’. She regarded the Manual as leading to ‘confusion in terms of understanding what is the active component, and rejected its essential tenor’.

Pharmaceutical substance – the Court’s conclusion on Interpharma’s argument

Weinberg J rejected Dr Elliot’s evidence and found that her view that the introduction of any non-active ingredient into a product prevents it from being a pharmaceutical, did not accord with the law as authoritatively determined in Boehringer and could not be reconciled with Heerey J’s approval of the Manual, and its analysis of the concept of a pharmaceutical substance (which was generally accepted as correct by the Full Court). Her approach would effectively mean that section 70 had almost no function to perform as almost every pharmaceutical product will consist of a combination of individual substances, some of which may be intrinsically therapeutic (active ingredients), while others serve different, albeit essential, roles. To restrict the capacity to extend a patent to those unlikely cases where every component of the compound is itself therapeutically useful would be to deprive the section of any real utility, and largely defeat the purpose of its enactment.