Australia: Federal Court delivers significant judgment allowing launch of generic CRESTOR (rosuvastatin)


Justice Jagot of the Federal Court of Australia has found three patents protecting AstraZeneca's CRESTOR (rosuvastatin) product invalid.

The revocation of the low dose HeFH and cation patents, subject to any appeal by AstraZeneca, opens the door for the many generic pharmaceutical companies with ARTG registrations (including those not party to the proceedings) to launch rosuvastatin products.

AstraZeneca has not yet announced an appeal against the judgment, but has issued a press release saying it is considering all legal options.

Of particular interest to originators and generics alike is the approach of the Court to the question of the "starting point" for the purposes of assessing inventive step. We consider this, and some other aspects of the decision, below.


Rosuvastatin is a blockbuster statin, with total Australian annual sales of approximately $350 million.

An API patent, ie, a patent protecting the rosuvastatin chemical compound, was never filed in Australia. AstraZeneca does own a number of secondary Australian patents relating to rosuvastatin, including those asserted in this proceeding.

The generic parties, Apotex, Watson and Ascent, each attempted to launch generic versions of rosuvastatin in April 2012. AstraZeneca was awarded injunctions in late 2011 and early 2012 restraining the launch of these generic rosuvastatin products.

ARTG registrations for rosuvastatin products are also held by several other pharmaceutical companies.

Summary of the case

AstraZeneca asserted the following three patents against Apotex, Watson and Ascent.

  • AU200023051 (low dose patent), relating to the use of a 'low dose' (most importantly, doses of 5 or 10mg) of rosuvastatin to treat hypercholesterolemia,
  • AU2002214165 (HeFH patent), relating to the use of rosuvastatin to treat the condition heterozygous familialhypercholesterolemia (HeFH), a genetic condition that is characterised by hypercholesterolemia, and
  • AU200051842 (cation patent), relating to a pharmaceutical formulation of rosuvastatin and an inorganic salt having a multivalent cation.
    Each of these patents is a 'secondary' patent.

Her Honour held that each of the three patents was invalid and liable to revocation. Her Honour also considered whether the patents would have been infringed if they were valid, and if a number of grounds for revocation asserted by the generics were not made out. A summary of Her Honour's conclusions is as follows:

Patent Grounds for revocation made out Infringed? (had the patent been valid)
Low dose patent Lack of entitlement (wrong inventor named); novelty; inventive step Only with respect to 5 and 10mg dosages; infringement by supply of other dosages not proven by AstraZeneca on the evidence
HeFH patent Lack of novelty; inventive step; manner of manufacture (invention disclosed on face of patent) Not proven by AstraZeneca on the evidence.
Cation patent Novelty (as a result of invalid priority date claim); inventive step Yes (except for Apotex's products that do not contain titanium dioxide and ferric oxide)

Our note focuses on the reasons the asserted claims of each patent were found invalid on the grounds of lack of inventive step and novelty.

Inventive step

One of the key conclusions that Jagot J reached, relevant to the validity of each of the patents in suit, was the way in which the Court was to consider whether an invention claimed in a patent possesses an "inventive step". As this issue was of importance to each of the patents, it was considered before issues specific to those patents.

To be valid, a patent must possess an "inventive step". Under the Patents Act, an invention is considered to involve an inventive step unless it would have been obvious to a person skilled in the art of the relevant patent in light of the "common general knowledge" at that time, either separately from or together with prior art information (eg, a publication that would have been located through a literary search) that would have been available to them.

An important issue in a number of recent pharmaceutical patent cases has been whether knowledge of the pharmaceutical compound in issue can be assumed as part of the starting point for an invention if knowledge of that compound is not part of the "common general knowledge".

This is a significant issue relating to the validity of many pharmaceutical patents. It is particularly relevant to 'secondary' patents filed after disclosure of the pharmaceutical compound itself. Many of these patents are filed before the pharmaceutical has been marketed, and so it is relatively unlikely the compound will form part of the common general knowledge. A much higher hurdle is faced by a patent challenger if the relevant compound is not available as part of the "starting point" for the invention.

Jagot J held that the inventions identified in each of the patents in suit presupposed the existence of rosuvastatin. Knowledge of rosuvastatin was not, in view of the patents, part of the invention. This resulted in a lower threshold for the generic parties to demonstrate that each of the patents in suit lacked an inventive step (in which they were successful).

Recent Federal Court cases have differed in the approach taken to this aspect of determining the presence or absence of an inventive step. On Jagot J's reasoning, it is a case-specific matter to determine by reference to the specification. Applying Jagot J's reasoning, it may become relatively easier to revoke patents on the base of a lack of inventive step if they express a problem to be solved in relation to a particular pharmaceutical (which is common for secondary pharmaceutical patents).

Low dose patent


The low dose patent was found to lack novelty when compared with documents referred to as the 471 patent and the Watanabe article.

The 471 patent, filed by Shionogi, is an 'API patent'. The 471 patent discloses a class of compounds suitable for treating hypercholesterolemia. The claimed class of compounds potentially included millions of different compounds including rosuvastatin. However, rosuvastatin was identified and given as a specific example of a compound suitable for treating hypercholesterolemia. The patent also disclosed a range of dosages for administration. The doses claimed in the low dose patent fell within these ranges. Therefore, the invention claimed in the low dose patent was disclosed in the 471 patent.

Jagot J contemplated that other compounds falling within the general class that were not specifically identified may not have been disclosed, however, given the very specific identification of rosuvastatin, that was not relevant.

The Watanabe article disclosed that rosuvastatin had greater activity than known statins pravastatin and lovastatin, and therefore greater potency in treating hypercholesterolemia. Watanabe did not expressly disclose the 5 to 10mg dosage range. However, Jagot J held that the skilled addressee of the low dose patent, armed with common general knowledge would have arrived at the claimed doses. The Watanabe article therefore disclosed the invention claimed in the low dose patent.

Lack of inventive step

Jagot J considered the relevant invention to be the discovery of a dosage range of a compound and that this invention was made on the assumption that the existence and nature of rosuvastatin was known. On this basis, her Honour held that the invention lacked an inventive step as it amounted to no more than the identification of a conventional starting dose for a compound within a known class for a known purpose.

Jagot J also held that, even if her view of the invention was incorrect, the low dose patent lacked an inventive step when compared with the 471 patent and the Watanabe article. The disclosure in both of these documents would have led the skilled addressee as a matter of course to try the claimed invention in the expectation "it might well produce a useful alternative to or a better result than currently achieved in the field". The existence of 11 (according to AstraZeneca) other potential statin candidates at the priority date did not detract from this conclusion.

HeFH patent


The HeFH patent was found to lack novelty by reason of each of the following prior art disclosures:

  • A SCRIP article that reported a study had recommended an aggressive approach to treatment of HeFH using statins, by reference to atorvastatin and simvastatin. The SCRIP article suggested that other "superstatins" in development, including rosuvastatin, could also fill the role.
  • An open label extension study under which patients were prescribed rosuvastatin. This trial was preceded by a clinical trial comparing the effects of rosuvastatin and atorvastatin in patients with HeFH.
  • The low dose patent, and a number of other publications, which disclosed use of rosuvastatin to treat hypercholesterolemia generally although not HeFH specifically. These were novelty destroying as the person skilled in the art would have therefore understood it could be used to treat HeFH.

Lack of inventive step

Her Honour considered the claimed invention to lie in using rosuvastatin (which was assumed to exist) as a method to treat HeFH. Her Honour also found that even if the invention didn't require the assumption of rosuvastatin's existence, rosuvastatin was part of the relevant common general knowledge for the HeFH patent. Given knowledge of the existence of rosuvastatin (either as an assumption on which the invention was based or through the common general knowledge), it was obvious to use rosuvastatin to treat HeFH.

Cation patent

Priority date problems

The cation patent claimed a priority date from a United Kingdom patent application (priority application) filed in January 2000. The generic parties successfully challenged the priority claim.

The cation patent had been significantly amended during the course of Australian prosecution, such that it was not entitled to claim priority from the United Kingdom patent.

The priority application related to a pharmaceutical composition of rosuvastatin and a tribasic phosphate salt in which the cation is multivalent. This composition was said to have advantageous stability. The priority application contained no reference to pharmaceutical formulations that did NOT include tribasic phosphate. However, none of the claims of the cation patent is limited to a composition containing a tribasic calcium phosphate salt – in fact, such a composition is expressly excluded from the claims. The cation patent was therefore not eligible to claim priority from the priority application.

Lack of novelty as a result of deferred priority date

Despite being unable to claim the priority date from the priority application, Jagot J held that the cation patent was not novel when compared to the priority application (as well as a number of related AstraZeneca patents validly claiming priority from it). These documents contained essentially the same disclosure as the cation patent.

Jagot J accepted AstraZeneca's argument that the cation patent claimed a pharmaceutical composition of rosuvastatin with a tablet coating comprising titanium dioxide and ferric oxide (inorganic salts in Jagot J's opinion with multivalent cations). Such a composition was disclosed in the priority application.

Lack of inventive step

Jagot J held that at the priority date, coatings containing titanium dioxide and ferric oxide were commercially available and commonly used (even if a compound being formulated had no stability issues). Her Honour held that there was therefore no invention in applying such a coating to a known compound. As the invention was found to presuppose knowledge of rosuvastatin, it was therefore not inventive to add such a coating to it. It was also accepted by her Honour that rosuvastatin was known by the deferred priority, and so similarly, it was not inventive to add a coating.

A copy of Jagot J's decision can be found here: Apotex Pty Ltd v AstraZeneca AB (No 4) [2013] FCA 162.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

To print this article, all you need is to be registered on

Click to Login as an existing user or Register so you can print this article.

Some comments from our readers…
“The articles are extremely timely and highly applicable”
“I often find critical information not available elsewhere”
“As in-house counsel, Mondaq’s service is of great value”

Mondaq Advice Centre (MACs)
Up-coming Events Search
Font Size:
Mondaq on Twitter
Register for Access and our Free Biweekly Alert for
This service is completely free. Access 250,000 archived articles from 100+ countries and get a personalised email twice a week covering developments (and yes, our lawyers like to think you’ve read our Disclaimer).
Email Address
Company Name
Confirm Password
Mondaq Topics -- Select your Interests
 Law Performance
 Law Practice
 Media & IT
 Real Estate
 Wealth Mgt
Asia Pacific
European Union
Latin America
Middle East
United States
Worldwide Updates
Check to state you have read and
agree to our Terms and Conditions

Terms & Conditions and Privacy Statement (the Website) is owned and managed by Mondaq Ltd and as a user you are granted a non-exclusive, revocable license to access the Website under its terms and conditions of use. Your use of the Website constitutes your agreement to the following terms and conditions of use. Mondaq Ltd may terminate your use of the Website if you are in breach of these terms and conditions or if Mondaq Ltd decides to terminate your license of use for whatever reason.

Use of

You may use the Website but are required to register as a user if you wish to read the full text of the content and articles available (the Content). You may not modify, publish, transmit, transfer or sell, reproduce, create derivative works from, distribute, perform, link, display, or in any way exploit any of the Content, in whole or in part, except as expressly permitted in these terms & conditions or with the prior written consent of Mondaq Ltd. You may not use electronic or other means to extract details or information about’s content, users or contributors in order to offer them any services or products which compete directly or indirectly with Mondaq Ltd’s services and products.


Mondaq Ltd and/or its respective suppliers make no representations about the suitability of the information contained in the documents and related graphics published on this server for any purpose. All such documents and related graphics are provided "as is" without warranty of any kind. Mondaq Ltd and/or its respective suppliers hereby disclaim all warranties and conditions with regard to this information, including all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement. In no event shall Mondaq Ltd and/or its respective suppliers be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use or performance of information available from this server.

The documents and related graphics published on this server could include technical inaccuracies or typographical errors. Changes are periodically added to the information herein. Mondaq Ltd and/or its respective suppliers may make improvements and/or changes in the product(s) and/or the program(s) described herein at any time.


Mondaq Ltd requires you to register and provide information that personally identifies you, including what sort of information you are interested in, for three primary purposes:

  • To allow you to personalize the Mondaq websites you are visiting.
  • To enable features such as password reminder, newsletter alerts, email a colleague, and linking from Mondaq (and its affiliate sites) to your website.
  • To produce demographic feedback for our information providers who provide information free for your use.

Mondaq (and its affiliate sites) do not sell or provide your details to third parties other than information providers. The reason we provide our information providers with this information is so that they can measure the response their articles are receiving and provide you with information about their products and services.

If you do not want us to provide your name and email address you may opt out by clicking here .

If you do not wish to receive any future announcements of products and services offered by Mondaq by clicking here .

Information Collection and Use

We require site users to register with Mondaq (and its affiliate sites) to view the free information on the site. We also collect information from our users at several different points on the websites: this is so that we can customise the sites according to individual usage, provide 'session-aware' functionality, and ensure that content is acquired and developed appropriately. This gives us an overall picture of our user profiles, which in turn shows to our Editorial Contributors the type of person they are reaching by posting articles on Mondaq (and its affiliate sites) – meaning more free content for registered users.

We are only able to provide the material on the Mondaq (and its affiliate sites) site free to site visitors because we can pass on information about the pages that users are viewing and the personal information users provide to us (e.g. email addresses) to reputable contributing firms such as law firms who author those pages. We do not sell or rent information to anyone else other than the authors of those pages, who may change from time to time. Should you wish us not to disclose your details to any of these parties, please tick the box above or tick the box marked "Opt out of Registration Information Disclosure" on the Your Profile page. We and our author organisations may only contact you via email or other means if you allow us to do so. Users can opt out of contact when they register on the site, or send an email to with “no disclosure” in the subject heading

Mondaq News Alerts

In order to receive Mondaq News Alerts, users have to complete a separate registration form. This is a personalised service where users choose regions and topics of interest and we send it only to those users who have requested it. Users can stop receiving these Alerts by going to the Mondaq News Alerts page and deselecting all interest areas. In the same way users can amend their personal preferences to add or remove subject areas.


A cookie is a small text file written to a user’s hard drive that contains an identifying user number. The cookies do not contain any personal information about users. We use the cookie so users do not have to log in every time they use the service and the cookie will automatically expire if you do not visit the Mondaq website (or its affiliate sites) for 12 months. We also use the cookie to personalise a user's experience of the site (for example to show information specific to a user's region). As the Mondaq sites are fully personalised and cookies are essential to its core technology the site will function unpredictably with browsers that do not support cookies - or where cookies are disabled (in these circumstances we advise you to attempt to locate the information you require elsewhere on the web). However if you are concerned about the presence of a Mondaq cookie on your machine you can also choose to expire the cookie immediately (remove it) by selecting the 'Log Off' menu option as the last thing you do when you use the site.

Some of our business partners may use cookies on our site (for example, advertisers). However, we have no access to or control over these cookies and we are not aware of any at present that do so.

Log Files

We use IP addresses to analyse trends, administer the site, track movement, and gather broad demographic information for aggregate use. IP addresses are not linked to personally identifiable information.


This web site contains links to other sites. Please be aware that Mondaq (or its affiliate sites) are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of these third party sites. This privacy statement applies solely to information collected by this Web site.

Surveys & Contests

From time-to-time our site requests information from users via surveys or contests. Participation in these surveys or contests is completely voluntary and the user therefore has a choice whether or not to disclose any information requested. Information requested may include contact information (such as name and delivery address), and demographic information (such as postcode, age level). Contact information will be used to notify the winners and award prizes. Survey information will be used for purposes of monitoring or improving the functionality of the site.


If a user elects to use our referral service for informing a friend about our site, we ask them for the friend’s name and email address. Mondaq stores this information and may contact the friend to invite them to register with Mondaq, but they will not be contacted more than once. The friend may contact Mondaq to request the removal of this information from our database.


This website takes every reasonable precaution to protect our users’ information. When users submit sensitive information via the website, your information is protected using firewalls and other security technology. If you have any questions about the security at our website, you can send an email to

Correcting/Updating Personal Information

If a user’s personally identifiable information changes (such as postcode), or if a user no longer desires our service, we will endeavour to provide a way to correct, update or remove that user’s personal data provided to us. This can usually be done at the “Your Profile” page or by sending an email to

Notification of Changes

If we decide to change our Terms & Conditions or Privacy Policy, we will post those changes on our site so our users are always aware of what information we collect, how we use it, and under what circumstances, if any, we disclose it. If at any point we decide to use personally identifiable information in a manner different from that stated at the time it was collected, we will notify users by way of an email. Users will have a choice as to whether or not we use their information in this different manner. We will use information in accordance with the privacy policy under which the information was collected.

How to contact Mondaq

You can contact us with comments or queries at

If for some reason you believe Mondaq Ltd. has not adhered to these principles, please notify us by e-mail at and we will use commercially reasonable efforts to determine and correct the problem promptly.