The ongoing saga of Lundbeck's fight for its patent on the widely used anti-depressant Lexapro has culminated in an extraordinary decision by the Patents Office (Alphapharm Pty Ltd, Sigma Pharmaceuticals (Australia) Pty Ltd, Apotex Pty Ltd, Sandoz Pty Ltd v H Lundbeck A/s  APO 36). This case has seen Lundbeck secure an extension of time of some 121 months to file a section 70 application in order to extend the term of one of its patents.
The fact an extension of term has been granted is not in itself unusual. The Commissioner has previously granted an extension of time in relation to section 70 applications. What places this decision in the realm of the extraordinary is the length of the extension, probably the longest extension ever granted by the Patents Office. This is combined with the fact that the decision to grant the extension was made at a time when the relevant patent had already expired and when there was a number of generic entrants, some of which have been listed on the PBS for more than two years.
The patent in issue is Lundbeck's patent number 623144 entitled '(+)-enantiomer of citalopram and the process of the preparation thereof'. The (+)-enantiomer salt (escitalopram oxalate) is marketed by Lundbeck under the brand name Lexapro.
THE EXTENSION OF TERM PROVISIONS
Section 70 of the Patents Act 1990 (Act) outlines the requirements for an application for an extension of term of a pharmaceutical substance.
Further, the Act sets out the timing requirements for filing an application under section 70. It provides that an application for an extension of term must be made during the term of the patent and within six 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 pharmaceutical substances reference to in subsection 70(3); or
- the date of commencement of this section.
LUNDBECK'S ORIGINAL EXTENSION OF TERM WAS INVALID
The patent has been subject of numerous legal challenges, not only to an extension of term that was previously granted by the Patents Office but also to the validity of the patent itself. These challenges ultimately culminated in a special leave application to the High Court, which was refused on 11 December 2010.
Although the validity of the patent had been upheld on 11 June 2009, the Full Federal Court1 held that the extension of term of the patent that had been granted originally had been referenced to the wrong pharmaceutical and, consequently, the register was rectified to remove the previously granted extension of term.
The Full Federal Court found that Lundbeck's pharmaceutical Citalopram, which is marketed under the brand name Cirpamil, necessarily contained the '(+)-enantiomer of citalopram' as it is a racemate salt (ie it existed as a mixture of (+)-citalopram and (-)- citalopram). Consequently, for the purposes of section 70 and 71 of the Act, the 'first goods included on the ARTG that contained, or consisted of' (+)-citalopram was Cipramil. Cipramil was first registered on the ARTG on 9 December 1997. As Lundbeck's original extensionof- term application was referenced to Lexapro (the (+) enantiomer of citalopram) and filed on 22 December 2003, the Full Federal Court1 held that the application was out of time and that the extension should be removed.
LUNDBECK'S SECOND APPLICATION FOR AN EXTENSION OF TERM
As a consequence of the removal of the extension of term, the patent expired on 13 June 2009. However, on 12 June 2009, one day prior to the expiry of the patent, Lundbeck filed a second extension-of-term application in relation to the patent based on Cipramil together with an extensionof- time application under section 223 of the Act.
The applications were opposed by four parties, who had launched generic products on the expiry of the original patent term.
Section 223 of the Act allows an extension of time to do a 'relevant act'. The opponents argued that Lundbeck could not seek an extension of time in relation to a section 70 application. Regulation 22.11(4) specifically excludes the following act for the purposes of section 223:
'Filing, during the term of a standard patent as required by subsection 71(2) of the Patents Act, an application under section 70 (1) of the Act for an extension of term of the patent.'
Although the hearing officer acknowledged that there was at least an argument that, when read literally, the regulation excluded an extension-of-time application in relation to an extension-of-term application, the hearing officer found that the regulation should be construed in a purposive manner that allowed an extension of time application to be filed 'during the term of the patent'.
As Lundbeck had filed its extension-of-term application a day prior to the patent expiring, it was entitled to have its section 223 request determined.
SECTION 223 CONSIDERATION
Pursuant to section 223 of the Act, in obtaining an extension of time an applicant must show that a relevant act was not done within a certain time because of:
- an error or omission by the person concerned or by his agent or attorney; or
- circumstances beyond the control of the person concerned.
The hearing officer found that there was a causative error that enlivened section 223 of the Act because Lundbeck had mistakenly thought that Cipramil was not a relevant good in relation to the patent. Further, the hearing officer found that Lundbeck continued to hold this belief until at least 11 June 2009 when the Full Federal Court handed down its decision. This is despite the fact that the Full Federal Court ultimately affirmed the first instance decision, which was issued on 24 April 2008.
As section 223 of the Act is a discretionary remedy, the hearing officer considered a number of discretionary factors and ultimately determined that the extension of time should be granted despite the fact that Lundbeck sought an extension of an unprecedented 121 months.
The discretionary factors that were considered include:
- Whether there had been unreasonable delay - The hearing officer referred to the Federal Court decision of Merck v Arrow in which it was held that an ARTG registered product that 'contained' the claimed product (even as an impurity) was sufficient for the purposes of section 70(3) of the Act. Although this decision was issued in November 2005, the Commissioner found that there was still uncertainty in the field and that given the decision had been undefended and given Lundbeck's strong belief that it would win its case on appeal, it was reasonable for Lundbeck to wait for the appeal process to be finalised. In any event, the Commissioner would not have been able to make a decision on an alternative section 70 application until the fate of the first extension was known. Therefore, the hearing officer was satisfied that the patentee did not cause any unreasonable delay.
- The patentee's interests - The hearing officer took into account the fact that if the patent were extended based on the ARTG registration of Cipramil, this would add an additional 3.5 years to the patent and the effective patent term would be 9.5 years. Consequently, the extended term would be closer to a 15-year effective patent term intended by the extension-of-term scheme introduced into the Act and would better compensate Lundbeck.
- Third-party interests - As outlined above, since the expiry of the original term of the patent on 13 June 2009, third parties commenced selling their generic escitalopram products and a number of those products had been listed on the PBS. A number of these parties opposed the section 223 application on the basis that the current situation would not have arisen if Lundbeck acted sooner, as they would have been able to delay the launch of their products until after the extension-of-term application had been determined. Instead, Lundbeck filed its section 223 application on the day prior to the expiry of the original term of the patent and the application was only advertised after the expiry of the patent on 23 July 2009. However, the hearing officer held that third parties entered the market as soon as the original term had expired to obtain a 'market advance' and this entry was a) within any potentially available statutory extension period and b) prior to the patentee exhausting all avenues of appeal. Consequently, the third parties launched in the face of a known commercial risk and the disadvantages of doing so could not be attributed to any delay occasioned by Lundbeck.
- Public interest - The opponents argued that there was a significant public interest against extending the term of a patent that had expired. Particularly, that this would force competitors from the market, which would significantly increase the cost of the drug. Although the Commissioner accepted that the cost of the drug was likely to increase, she noted that this would only be for a short time (being 3.5 years) and would always have been the case if the correct extension had been granted in the first place.
WHAT DOES THIS DECISION MEAN FOR PATENTEES WHO MAY HAVE REFERENCE THE WRONG PHARMACEUTICAL?
The practical effect of this decision is somewhat unclear. In her decision, the hearing officer clearly states that she could not have been able to make a decision on an alternative section 70 application until the fate of the first extension was known. Consequently, unless an extension-of-term application has been successfully challenged, the Commissioner is not able to determine an alternative section 70 application. This places a patentee in a predicament where an extension of term has been granted in relation to an inappropriate drug but the validity of the extension has not been challenged by any third party.
However, if an application for an extension of time to file an alternative section 70 application is not made immediately on becoming aware that the extension of term was based on an incorrectly referenced drug, an issue of unreasonable delay will arise. This is a disentitling factor when determining whether an extension of time will be granted.
In circumstances where the patentee has inadvertently referenced the wrong drug, it should carefully consider what steps should be taken to protect its interests.
This decision has been appealed and we will update you in relation to that appeal.
1Lundbeck A/S v Alphapharm Pty Ltd  FCAFC 70
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