Does the mere naming of a chemical compound destroy novelty?

It is well established in Australia that a claim will lack novelty if each essential feature is disclosed in a prior art document. What remains less clear, however, is the level of disclosure required to destroy novelty, particularly in chemical cases.

Enablement 
Traditionally, the requirement that the disclosure "enable" the skilled person to put the invention into practice was clear: "the antecedent statement must be such that a person of ordinary knowledge of the subject would at once perceive, understand, and be able practically to apply the discovery without the necessity of making further experiments and gaining further information before the invention can be made useful" (English Court of Chancery in Hill v Evans, approved by the Australian High Court in Olin Corporation v Super Cartridge).

More recently, a potentially inconsistent line of authority has developed, which casts doubt on the enablement requirement where the relevant claim relates to a chemical compound: "[w]here the prior publication discloses exactly what is claimed, there is anticipation" (Full Court obiter in H Lundbeck v Alphapharm, applied by the same judges in Apotex v Sanofi-Aventis).

Albany Molecular Research v Alphapharm
The apparent tension between these lines of authority is set to come under the judicial spotlight again. Albany Molecular Research, Inc (AMR) filed a notice of appeal from the decision in Albany Molecular Research v Alphapharm.

Figure 1: Fexofenadine (para regioisomer) 



Figure 2: Corresponding meta regioisomer
 

The dispute centres on the isolated compound fexofenadine (Figure 1). In the most significant aspect of the first instance decision, Justice Jessup considered whether claims to a substantially pure compound lack novelty. It was not in dispute that the closest prior art disclosed the isolated compound. However, Jessup found that the prior art did not disclose an effective means of preparing the isolated compound. After extensive consideration of expert evidence, Jessup was satisfied that following the instructions set out in the examples of the prior art would lead to a mixture of fexofenadine and the meta regioisomer (Figure 2), not isolated fexofenadine.

The validity of the relevant claims pivoted on whether, given these findings of fact, the claims were novel.

Jessup felt that he was bound by the law as expounded in Lundbeck and Apotex, notwithstanding the High Court decision in Olin Corporation. In siding with the closest factual precedent, Jessup held that "the disclosure of a compound by exact naming in the prior art is sufficient, of itself, to constitute anticipation". It is not necessary to prove that the prior art enables the manufacture of the claimed compound. The judge's reasoning leads to the unusual result that although the relevant claims are inventive, they lack novelty. Jessup’s orders revoking the relevant claims of AMR’s patent have been stayed pending the appeal decision.

Patent Office position 
Interestingly, Australian patent examiners do not appear to be following the decisions in Lundbeck, Apotex and AMR, as no reference is made to any of them in the relevant section of the examiner’s manual. The manual asserts that the definition of "enabling disclosure" in chemical situations is "one sufficient in the case of a claim to a chemical compound to enable those skilled in the art to make the compound", citing the 20th-century English authority Pall Corp v Commercial Hydraulics, which is consistent with the traditional Hill v Evans approach. However, it is not clear whether the absence of references to more recent Australian authority is deliberate, as the section of the manual has not been updated in five years.

Relevance to pharmaceutical patent applicants
The AMR decision has particular relevance for chemical and pharmaceutical companies operating in Australia, and implications for the novelty of some chemical compound claims. As the law and Patent Office practice stand, originator companies with compound claims accepted by the Patent Office may find it difficult to defend third-party novelty attacks in opposition or court proceedings, particularly where prior art enablement is at issue. It is likely to be a number of years before the available avenues of appeal from the first instance AMR decision are exhausted and a higher degree of legal certainty is restored.