The question of how long originators of a new pharmaceutical medication should hold their patent monopoly has been extensively debated and, with the competing interests of originators and generic pharmaceutical manufacturers, remains an important issue. Special provisions already exist in Australian law allowing holders of a pharmaceutical patent to apply for an extension of the normal 20 year term of their patent. These provisions take into account the additional time needed for clinical trials and regulatory approval before the invention can be marketed. However, the deadline for applying for an extension of term is not straightforward, and the application must be carefully timed.
A recently published decision of the High Court of Australia (Alphapharm Pty Ltd v H Lundbeck A-S  HCA 42) has clarified when the law affords the Commissioner of Patents the power to grant an extension of time in which to make for an application for an extension of term of a pharmaceutical patent.
In Australia, the term of pharmaceutical patents can be extended for up to five years. Subsection 71(2) of the Patents Act 1990 states:
An application for an extension of the term of a standard patent 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 Australian Register of Therapeutic Goods of goods that contain, or consist of, any of the pharmaceutical substances referred to in subsection 70(3);
- the date of commencement of this section.
Citalopram is a racemic mixture of the (-)-enantiomer and the (+)-enantiomer (escitalopram) of a chemical compound and is used as an anti-depressant marketed as “CIPRAMIL”. This mixture was the subject of a patent originally filed by Lundbeck in 1977. In 1989, Lundbeck filed a patent application for only the “(+)-enantiomer of citalopram and process for the preparation thereof” (“the escitalopram patent”) which was subsequently granted in August 1992. This (+)-enantiomer is called Escitalopram and also acts as an anti-depressant, marketed as “LEXAPRO”.
Escitalopram was added to the Australian Register of Therapeutic Goods (ARTG) on 16 September 2003 and Lundbeck applied for an extension of term for its patent in December 2003, within the 6 month timeframe required. However Alphapharm (a generic pharmaceuticals manufacturer) argued against granting the extension because citalopram itself was added to the ARTG on December 1997.
Alphapharm reasoned that as citalopram contained escitalopram, the first inclusion into the ARTG of escitalopram should also be December 1997, and that the application for extension of term was therefore made after the deadline of six months from inclusion on the register. Alphapharm was initially successful in having the extension of term application denied.
Extension of Time
The Patents Act 1990 contains provisions that confer on the Commissioner of Patents the power to grant an extension of time for completing ‘a relevant act’. For the Commissioner to grant an extension of time, it must be shown that the failure to complete the act was because of “an error or omission by the person concerned or by his or her agent or attorney” or “circumstances beyond the control of the person concerned”.
The day before the escitalopram patent was due to expire, Lundbeck submitted an application for an extension of its term, based on citalopram’s first inclusion in the ARTG, and an application for an extension of time. In short, having been prevented from acquiring an extension of term because the date of inclusion was ruled to be 1997 rather than 2003, Lundbeck sought a retrospective extension of the time in which they were permitted to make an application for an extension of term for the escitalopram patent on the basis that they did not know that its date of inclusion would be retrospectively ruled to have been 1997.
This extension of time request was for about 10 years and was initially allowed by the delegate of the Commissioner of Patents. Alphapharm opposed this decision through a series of court and tribunal hearings, but was unsuccessful, finally seeking leave to appeal to the High Court. This outcome was important to Alphapharm because once the 20 years of the escitalopram patent had passed it and other pharmaceutical manufacturers had launched their own generic version of escitalopram in the marketplace.
In relation to an extension of time, the Patent Act 1990 states:
The Commissioner must extend the time for doing a relevant act that is required to be done within a certain time if the act is not, or cannot be, done within that time because of an error or omission.
The term “relevant act” is defined in the Act as “an action (other than a “prescribed action”) in relation to a patent”. The Patent Regulations 1991states a “prescribed action” is “filing, during the term of a standard patent under subsection 71(2) of the Act, an application under subsection 70(1) of the Act for an extension of the term of the patent”. Alphapharm argued that the meaning of “relevant act” includes both time requirements set out in subsection 71(2) and, in effect, that the extension of time provisions are not available in relation to applying to extend the term of a patent. Alphapharm also argued that an extension of time for almost 10 years was unreasonable.
The High Court noted that there are two time requirements that must be satisfied; an application for an extension of term must be made during the term of the patent; and the application must be made within six months of the three dates in subsection 71(2). The High Court decided that the regulations only exclude the first requirement, of filing within the patent term, from the extension of time provisions and the provisions can still be used for the three dates in subsection 71(2). The extension of time provision can be used in conjunction with the extension of term as long as the application is filed before the patent expires. This decision confirms the earlier rulings of the Patent Office, the Administrative Appeals Tribunal and the Federal Court of Australia. It is notable, however, that the High Court decided the issue by a narrow majority highlighting the ambiguous nature of the statutory drafting in the relevant sections.
It is possible, assuming the relevant conditions are met, to apply late for an extension of term using the extension of time provisions as long as the requests are made prior to the expiry of the patent. This ruling will be a relief to originators but will make it more difficult for generic pharmaceutical manufacturers to optimise the timing of their entry to market.
This case also highlights the critical importance of staying vigilant with regards to the status of patents, and to the interplay of timescales relating to patent term, date of grant, and regulatory inclusion. A quality firm of patent and trade mark attorneys should be able to provide a rigorous and pro-active system of reminders to help you to ensure that none of these critical deadlines is missed.