Invalidity finding on rosuvastatin patents upheld on appeal

In a decision handed down on 12 August 2014, AstraZeneca has lost its appeal to the Australian Full Federal Court regarding the invalidity finding for two patents protecting its cholesterol medication, Crestor™ (rosuvastatin).   It was further ordered that an interlocutory application be dismissed and for AstraZeneca to pay 80 % of the respondents’ costs.

Background

Initially, three patents were challenged by Apotex Pty Ltd, Watson Pharma Pty Ltd and Ascent Pharma Pty Ltd.  They claimed the use of rosuvastatin to treat hypercholesterolemia (AU2000023051; the -051 patent) and heterozygous familial hypercholesterolemia (AU2002214165; the -165 patent), as well as rosuvastatin in a pharmaceutical formulation (AU2000051842; the -842 patent).   Watson, Ascent and Apotex (‘the generic parties’) each proposed to supply generic versions of the rosuvastatin product in tablet form.  The proposed launch resulted in AstraZeneca alleging infringement of each of the three rosuvastatin patents.  In response, the generic parties each alleged that the claims on which AstraZeneca relied to assert infringement were invalid and should be revoked.

Decision at first instance

Apotex Pty Ltd v AstraZeneca AB (No 4) [2013] FCA 162

In March 2013, a single judge of the Federal Court of Australia found the three patents protecting rosuvastatin to be invalid and liable to be revoked.

It was concluded that all the claims of the -051 patent were invalid and the patent should be revoked. The claims on which AstraZeneca relied to assert infringement of the -165 and -842 patents were also found to be invalid and liable to revocation.  Finally, the judge ordered that the generic parties be released from any undertakings that they had given and interlocutory injunctions by which they were bound.  Further details for the decision at first instance can be found here.

Basis of the Appeal

Astrazeneca AB & Anor v Apotex Pty Ltd [NSD603/2013]

AstraZeneca filed an appeal against this decision in April 2013, challenging most of the primary judge’s key findings.  AstraZeneca’s appeal included arguments that the judge erred in finding the -051 and -842 patents invalid for lack of novelty and lack of inventive step .  An appeal was not submitted in relation to the -165 patent.  This patent was subsequently revoked.

In a further attempt to have the court reconsider the revocation of the patents, AstraZeneca also filed an interlocutory application seeking to amend its notice of appeal to encompass the ‘Raising the Bar’ law changes, implemented early last year.

Outcome

Astrazeneca AB & Anor v Apotex Pty Ltd [2014] FCFCA 99

In a decision handed down on 12 August 2014, all five judges of the Full Federal Court dismissed the appeal by AstraZeneca in relation to both patents.   While the court disagreed with the lack of novelty finding for the -051 patent, it upheld the primary judge’s decision concerning obviousness.  The court agreed with the primary judge’s finding that the claims of the -842 patent lacked novelty and further found that the claims were also invalid for lack of fair basis.

The court also dismissed the interlocutory application and was critical of AstraZeneca for not identifying its intentions to rely on the law changes earlier.

Infringement of the -051 patent was also considered, in relation to the 20 mg tablet which could result in the consumer ‘splitting’ the tablet to obtain a 10 mg dosage.  The court found at [444] that ‘the more difficult it is for the patentee to establish that there is a likelihood of widespread infringing use, the more difficult it should be for the patentee to obtain injunctive relief in the broad terms restraining any supply of the relevant product’.  It was therefore found that while some consumers may partake in an infringing use, it would not be sufficient to justify the grant of an injunction.

It is not yet known whether there will be an appeal against this decision.  However, an appeal to Australia’s highest court, the High Court, would require special leave of that court to proceed.

If you have any specific enquiries about the rosuvastatin decision in Australia, please contact Paul Jones or Debra Tulloch.

This article was written by Dr Ellen Reid.