Enabling disclosure no longer required to anticipate a patent claim

A recent decision of the Australian Federal Court has cast doubt on the widely-accepted notion that a “paper anticipation” is insufficient to invalidate a patent claim.

In Albany Molecular Research Inc v Alphapharm Pty Ltd [2011] FCA 120, Albany sued Alphapharm (amongst other generics manufacturers) for infringement of Australian Patent No. 699799. This patent claimed fexofenadine hydrochloride in substantially pure form – and also pharmaceutical compositions and methods of treating allergic conditions using such compounds.

Alphapharm was allegedly selling antihistamine products comprising the claimed compounds.

In response, Alphapharm counter-claimed for revocation of AU 699799, on grounds including novelty and obviousness.

The decision in relation to both novelty and obviousness is considered somewhat controversial. Both arguments relied on the same two prior art documents that described, inter alia, fexofenadine and methods for its synthesis. What the prior art lacked, however, was an enabling disclosure as to how one could obtain fexofenadine in substantially pure form. Thus, there was a mere “paper anticipation”, which, Albany contended, should have resulted in the counter-claim being thrown out.   The Court nonetheless rejected such arguments.

Jessup J, sitting alone, felt bound by recent decisions of the Full Federal Court (eg Lundbeck v Alphapharm Pty Ltd [2009] FCAFC 70; and Apotex v Sanofi Aventis [2009] FCAFC 134), which were factually similar to the present case. His Honour held that the “disclosure of a compound by exact naming in the prior art is sufficient, of itself, to constitute anticipation”, at [36].

As suggested above, this decision would appear ripe for Appeal based on the proposition that Lundbeck and Apotex were applied incorrectly – a possibility alluded to earlier in his Honour’s judgment.   His Honour then went on to consider whether the claims were obvious – in other words, whether fexofenadine in substantially pure form was obvious over fexofenadine, per se, based either on the teaching of the prior art, or the routine abilities of one nominally skilled in the art. It was held that the prior art did not teach a means of preparing fexofenadine in a substantially pure form – and that, on evidence, such compounds could not have been obtained by mere routine. The judge found that the synthetic method described in the patent (ie wherein the substantially pure fexofenadine hydrochloride was isolated from two undesired regioisomers that are by-products of the synthetic methods otherwise described) would not have been obvious to one of ordinary skill in the art in Australia.  His Honour thereby concluded that claims to substantially pure fexofenadine, whilst lacking in novelty, were indeed inventive.

This proposition is something of a misnomer and in our opinion further tempts Appeal in that it appears to have moved Australian law out of kilter with most other major jurisdictions.   On 13 April 2011, in a largely unsurprising development, Albany appealed the decision.

The matter will now be heard by the Full Bench of the Federal Court.   We will continue to monitor developments in this case. For completeness, we note that the ground of “false suggestion” was also raised in relation to the actions of Albany’s predecessor in title during initial prosecution before the Australian Patent Office. Watch this space.