Patent Term Extensions

In Australia the application of the Patent Term Extension provisions of the Patents Act 1990 have been construed narrowly so that PTEs are applicable to only certain types of pharmaceutical patents.

PTEs were introduced in 1998, pursuant to the Intellectual Property Laws Amendment Act 1998 amended the Patents Act 1990 to provide for an extension of up to 5 years for a standard patent that claims a pharmaceutical substance.

Judicial interpretation of a pharmaceutical substance has been a fraught exercise, and a recent decision of the Federal Court of Australia (Commissioner of Patents v AbbVie Biotechnology Ltd [2017] FCAFC 129) has now ruled on the applicability of PTEs to Swiss-style claims.

In this article we discuss the Court's decision (that the Swiss-style claims cannot be the subject of PTEs in Australia) and consider the earlier judicial rulings which demark the boundaries of PTEs in Australia.

Background to PTEs

Section 70 - Extending a patent term

In order to obtain a PTE, the following requirements must be met:

a) section 70(2): the patent must, in substance, disclose and claim a pharmaceutical substance per se, or a pharmaceutical substance when produced by recombinant DNA technology;

b) section 70(3):

• goods containing or consisting of that pharmaceutical substance must be included in the Australian Register of Therapeutic Goods (ARTG); and
• the first regulatory approval for that pharmaceutical substance must have occurred more than 5 years after the date of the patent; and

c) section 70(4): the term of the patent must not have been previously extended.

Provided the requirements of the Act are satisfied, the term of the patent (in its entirety) may be extended.

Time for applying

Under section 71(2), an application for a PTE must be made during the term of the patent and within 6 months after the latest of the following dates:

• the date the patent was granted;
• the date of commencement of the first inclusion in the ARTG of goods that contain, or consist of, any of the pharmaceutical substances referred to in section 70(3);
• the date of commencement of the extension of term provisions (27 January 1999).

Pharmaceutical substance "per se"

The issue that has caused controversy in the construction of the Australian PTE provisions is the meaning of pharmaceutical substance "per se".

The meaning of pharmaceutical substance "per se" was comprehensively discussed by the Full Federal Court decision in Alphapharm Pty Ltd v H Lundbeck A/S [2015] FCAFC 138. This decision upheld the findings of the Federal Court in H Lundbeck A/S v Alphapharm Pty Ltd [2009] FCAFC 70.

Background

This case related to the Lundbeck Australian patent no 623144 which contains claims to the pharmaceutical substance escitalopram (the (+)-enantiomer of the compound citalopram):

Claim 1: (+)–1-(3-dimethylaminopropyl)–1-(4’-fluorophenyl)–1,3-dihydroisobenzofuran–5-carbonitrile and non-toxic acid addition salts thereof.

Citalopram is the subject of the Alphapharm Australian patent no 509445 and is a racemic mixture of the two enantiomers escitalopram and (-)-citalopram in equal proportion.

The issue in this appeal was whether escitalopram satisfied the requirement of pharmaceutical substance "per se" pursuant to section 70(2)(a).

Meaning of pharmaceutical substance "per se"

Alphapharm argued that Lundbeck’s patent was a claim in respect of the isolated or pure enantiomer (limited by a requirement of purity of manufacture), and it was not a claim to a pharmaceutical substance per se.

The Federal Court held at [65]:

the task is to construe the words of claim 1. Those words describe a product or substance. They do not suggest in any way that the product or substance must be isolated from other products or substances. There is nothing in claim 1 to suggest that the (+)-enantiomer is disclosed with a degree of purity. The racemate is no more than a mixture of the two enantiomers. Each of those two compounds is present in the racemate and can be separated. Further, at the relevant time, the relevant hypothetical skilled addressee was aware that the racemate contained both compounds and that the two compounds could be separated.

This decision was upheld on appeal by the Full Federal Court in Alphapharm Pty Ltd v H Lundbeck A/S [2015] FCAFC 138. Bennett , Nicholas and Yates JJ held at [92]:

The term “pharmaceutical substance per se” simply means the pharmaceutical substance “in itself”…

…it is clear that the claim describes a pharmaceutical substance per se. The substance was… a new chemical entity. The racemate and the (+)-enantiomer had different physico-chemical interactions manifested in different pharmacodynamics and pharmacokinetics… The claim is to (+)-citalopram, irrespective of how it is produced. The isolated (+)-enantiomer plainly qualifies as a pharmaceutical substance per se and the primary judge was correct in concluding that it satisfies s 70(2)(a) of the Act.

This decision gives important context to the most recent Full Federal Court decision of Commissioner of Patents v AbbVie Biotechnology Ltd [2017] FCAFC 129, in which the proper interpretation of the term ‘pharmaceutical substance’ for the purpose of interpreting section 70(2)(b) was considered in the context of PTEs for Swiss Style Claims.

The Abbvie decision

No patent extensions for Swiss Style Claims in Australia

After the Administrative Appeals Tribunal of Australia (AATA) decision in AbbVie Biotechnology Ltd v Commissioner of Patents [2016] AATA 682, patentees were hopeful of wider grants of PTEs in Australia. The…