28 February 2011

Anti-histamine Inventive… But Not Novel, Says Federal Court!

Albany Molecular Research Inc v Alphapharm Pty Ltd [2011] FCA 120 (18 February 2011)

A Judge in the Federal Court of Australia has found patent claims directed to an anti-histamine drug known by the non-proprietary name of fexofenadine to be lacking in novelty, and yet to involve an inventive step.

Many Australian practitioners have long thought that the scheme of the Australian Patents Act 1990, and specifically section 7, allows for the possibility that a claim could fail the test of novelty prescribed by subsection 7(1), and yet pass the test for inventive step that is separately prescribed in subsections (2) and (3).  While this is interesting to contemplate as an academic exercise, as a practical matter there is generally no need to devote significant effort to assessing inventive step once a want of novelty has been established.  Certainly this is the view of a majority of patent examiners at IP Australia, who are inclined to open objections with statements such as ‘…claim 1 lacks novelty (and does not involve an inventive step) in light of D1, which discloses…”.

But clearly this view is not shared by Justice Jessup of the Federal Court of Australia who, to be fair, no doubt felt somewhat constrained by certain precedential appeal decisions of the full bench of the court.

REGIOISOMERS

We have stated before on this blog that chemistry is not really our subject, so we hope that readers more knowledgeable in this area will bear with us.

This case involves regioisomers, which are a type of structural isomer – so Wikipedia tells us – also known as positional isomers.  Isomers are essentially groups of chemical compounds that have exactly the same chemical formula, but different geometric structures.  We have previously had cause on this blog to write about stereoisomers (see here), which are molecules that have not only the same chemical formula, but also exactly the same sequence of bonded atoms – it is only when their three-dimensional structure is examined that they can be seen to be distinguishable from one another.

Regioisomers are also molecules that have the same chemical formula, but they differ in the order in which the constituent atoms are bonded together.  Specifically, one or more functional groups change position on a parent structure.  Compounds that include benzene (i.e. aromatic compounds) can have many regioisomers, because functional groups, or substituents, can be located in a number of positions on a benzene ring.

Relevantly, it is often the case that a synthesis reaction intended to produce a particular compound which exists in the form of different isomers will necessarily result in a mixture of the different isomers, not all of which will be useful or desirable.

THE DISPUTE

Albany Molecular Research Inc (‘AMR’) is the patentee of Australian patent no. 699799, which essentially claims fexofenadine compounds, and more particularly one specific pharmaceutically-effective regioisomer of those compounds.  Alphapharm Pty Ltd, along with a number of other parties (collectively ‘the respondents’), manufacture and sell generic pharmaceutical products in which the active ingredient is fexofenadine hydrochloride.  It was not disputed that if the claims of AMR’s patent were valid, then the respondents’ products would infringe.

THE PRIOR ART

The primary prior art documents pertinent to AMR’s invention were a series of prior US patents, collectively known as ‘the Carr patents’, after one of the inventors.  The Carr patents disclose methods of synthesising compounds, which include fexofenadine, however they do not disclose any method of obtaining the desired fexofenadine regioisomer in a substantially pure form, isolated from two other undesired regioisomers.

THE ALLEGED INVENTION

The AMR patent specification discloses, and claims, various methods to prepare the desired fexofenadine regioisomer in a substantially pure form or, as Justice Jessup puts it at paragraph [13] of the decision, ‘compounds which are unembarrassed by the presence of meta regioisomers.’

However, claims to the methods were not principally in dispute.  The patent also includes claims directed to the resulting substantially pure compounds themselves (‘compound claims’).

The ultimate question in the case, therefore, was whether a claim to a compound can be valid when the compound is known in the prior art, but not known to exist, or have been produced, in an isolated form.

In other words… is the discovery or invention of a method to prepare and isolate a known compound – for the first time – sufficient to support a claim to the isolated compound per se?

TWO VIEWS ON NOVELTY

1. Only an enabling prior disclosure of the compound anticipates
AMR’s position in relation to novelty was that the compound claims are not anticipated, because the Carr patents do not provide an enabling disclosure in the sense required in Hill v Evans [1862] EngR 365; (1862) 1A IPR 1, i.e.

…the prior knowledge of an invention to avoid a patent must be knowledge equal to that required to be given by a specification, namely, such knowledge as will enable the public to perceive the very discovery, and to carry the invention into practical use. (Quoted at paragraph [17].)

Further authority for this position relied upon by AMR included Acme Bedstead Co Ltd v Newlands Brothers Ltd [1937] HCA 63 and Olin Corporation v Super Cartridge Co Pty Ltd [1977] HCA 23.  With regard to this last High Court ruling, Justice Jessup himself concluded (at [19]) that ‘[i]f Olin stood alone and were directly applicable to the facts of the present case, clearly it would have to be followed.’
2. Any prior disclosure of the compound anticipates
The respondents’ position in relation to novelty was that once a specific compound has been disclosed in the prior art, then it is no longer novel, and therefore cannot be patented.

For this proposition, the respondents relied upon recent judgments of the Full Court of the Federal Court of Australia in H Lundbeck A/S v Alphapharm Pty Ltd [2009] FCAFC 70 (which was previously discussed on this blog), and Apotex Pty Ltd v Sanofi-Aventis [2009] FCAFC 134.  As summarised by Justice Jessup (at [15]):

In Lundbeck …: “Where the prior publication discloses exactly what is claimed, there is anticipation”.  That was not the situation in Lundbeck itself, but it was in Apotex, in which case the court held that the disclosure of a particular enantiomer in the prior art anticipated a later patent which claimed that enantiomer, notwithstanding that a compound consisting only of that enantiomer had never, apparently, been made.

DECISION ON NOVELTY – ‘EXACT NAMING’ ANTICIPATES

Clearly, Justice Jessup was faced with two distinct, and arguably incompatible, lines of authority between which he had to choose.  On the one hand, Acme Bedstead and Olin are decisions of the High Court of Australia while, on the other, Lundbeck and (especially) Apotex are very much on-point to the facts of this case.  Both represent binding precedent on a single judge in the Federal Court.  In the end, the close relevance of the subject matter of Lundbeck and Apotex won out (at [36]):

In the view I take of the law as expounded in Lundbeck and Apotex, the disclosure of a compound by exact naming in the prior art is sufficient, of itself, to constitute anticipation.  As a single Judge of the court, I do not believe I am in any position to consider the consistency of these Full Court judgments with earlier authority, however high.  That authority was within the jurisprudence to which Bennett J gave extensive consideration in Lundbeck.
The prior disclosure was not enabling
Notwithstanding that he had already reached a conclusion on novelty on the above grounds, Justice Jessup went on to consider an alternative argument advanced by the respondents – essentially being that the Carr patents did indeed provide an ‘enabling disclosure’ of the invention defined by the compound claims.  This argument comes down to what the relevant skilled addressee would have understood, and been led to do as a matter of course, by following the teachings of the prior art. 

As Justice Jessup put it (at [38]):

What would be perceived and understood, and what could be practically applied (see Hill v Evans) are, of course, questions to be approached from the perspective of the skilled addressee.  … the parties called organic chemists of some standing in their profession to opine on these questions.  AMR called Prof Christopher Easton, Distinguished Professor at the Research School of Chemistry, Institute of Advanced Studies, Australian National University; [the respondents] called Prof David Black, Professor of Organic Chemistry at the University of New South Wales, … Prof Bruce Wild, Emeritus Professor in the Research School of Chemistry at the Australian National University; and … Dr Alan Robertson, Chief Executive Officer and Managing Director of Pharmaxis Ltd.

Following over 100 paragraphs of discussion of the evidence provided by these eminent experts, Justice Jessup concluded that the Carr patents did not disclose an effective means of preparing substantially pure fexofenadine, stating (at [151]) that:

…if I am wrong about the law as established in Lundbeck and Apotex, I would hold that the invention, so far as claimed in the claims which are presently relevant, was not anticipated by [the Carr patents].

INVENTIVE STEP

The conclusion on inventive step follows, to some extent, almost directly from the finding in relation to ‘enabling disclosure’.  On the basis of the same evidence, Justice Jessup stated (at [154]):

I do not accept that … a research group would have directly been led, as a matter of course, to try the [successful process] in the expectation that it might well provide a link in the synthetic chain for the production of fexofenadine …. Rather, I accept the submission made on behalf of AMR that … that example was much closer to what has been described as trying “each of numerous possible choices until one possibly arrived at a successful result, where the prior art gave either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful”…

Additional evidence was led by one group of respondents, to the effect that a research team in Canada had successfully synthesised fexofenadine in the late 1980’s or early 1990’s using a method that was allegedly obvious to at least one member of the team.  Justice Jessup rejected this evidence and line of reasoning on the basis that it fell far short of establishing that the synthesis method developed by the Canadian team would have been obvious at the time to the ordinary person skilled in the art in Australia.  Indeed, Justice Jessup pointed out that the evidence did not even establish that the Canadian research team considered the synthesis method to be obvious and not, for example, the result of some specific individual’s knowledge and specialist experience (see paragraph [160]).

The conclusion reached by Justice Jessup was, therefore – and despite having already found a lack of novelty – that (at [162]):

…I am not satisfied that the invention in suit would have been obvious to a person skilled in the relevant art in the light of the common general knowledge in Australia before the priority date.  It follows that the invention, so far as claimed in the product claims with which I am presently concerned, involves an inventive step.

OTHER ISSUES

The respondents’ also raised issues of lack of clarity (in relation to the phrase ‘substantial purity’), ‘manner of manufacture’ (i.e. the allegation that the claims did not define statutory subject matter) and ‘false suggestion’.  All of these were decided favourably to AMR.  Only the clarity issue holds any real additional interest, and so we may return to this in a subsequent article.

COMMENT

It appears to us that Justice Jessup has written this decision with a view to an appeal by AMR on the question of novelty.  Having found that the compound claims lacked novelty under the Lundbeck and Apotex standards, his honour could have stopped at that.  The greatest part of the decision is, in fact, taken up with discussion of the evidence relating to ‘enabling disclosure’, which Justice Jessup considered to be the ‘alternative case’ on novelty.  Of course, if the ruling on the primary case were to be overturned on appeal, then this part of the decision (which Justice Jessup himself highlighted as being pertinent if he were ‘wrong about the law as established in Lundbeck and Apotex’) would take on great importance.

Similarly, the ruling on inventive step – particularly in view of its apparent incongruousness – suggests a case ripe for appeal, notwithstanding that the Patents Act is structured in such a way that a finding of inventiveness without novelty is quite plausible.  In particular, the presence or otherwise of an inventive step is referenced to the knowledge of the ordinary person skilled in the art, while novelty is essentially an absolute test of prior disclosure (as was certainly the case here).  A novelty-destroying disclosure might be found anywhere, while a disclosure relevant to inventive step must be found in the common general knowledge in the relevant art, and/or those sources that would have been readily identified and considered by the skilled worker.

This is not, however, a case in which the anticipating prior art was outside the interest of the skilled person.  It was, rather, the closest relevant prior art for the purposes of assessing inventive step as well as novelty.  The fact that, in these circumstances, a claim could be found to be inventive, yet not novel, is an outcome quite likely to offend the sensibilities of a full bench of the Federal Court of Australia.  In the event of an appeal, it seems probable that the Full Court would seek to restore consistency by reversing either the novelty finding, or the inventive step finding.  There is High Court authority, in Acme Bedstead and Olin, to support a novelty finding (assuming Lundbeck and Apotex can be distinguished).  Reversal of the inventive step decision, however, may prove more difficult to justify, in the face of Justice Jessup’s detailed findings of fact.

For our own part, we do not think that it should be the law in Australia that the mere naming of a compound (or, indeed, any other invention) should be sufficient to anticipate a subsequent claim supported by an adequate disclosure of the means for putting the invention into effect.  Our understanding is that this is not consistent with the law in most other major jurisdictions.  Furthermore, taken to its logical conclusion, it would follow that even ‘disclosures’ of concepts in works of fiction might qualify as anticipating prior art.  Now that surely cannot be right?!

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