Introduction

In a final judgment of May 20 2016 the Supreme Court dismissed AstraZeneca's extraordinary appeals and confirmed the nullity in Spain of a European patent regarding sustained release formulations of quetiapine, which protected the blockbuster anti-psychotic drug commercialised by AstraZeneca as Seroquel Prolong®.

AstraZeneca was the holder of European patent 0 907 364 (EP'364), which designated Spain, among other countries. This patent claimed a sustained release formulation comprising quetiapine and a gelling agent.

Since 2011 court proceedings have taken place in several EU countries regarding the validity of this patent (eg, Spain, the United Kingdom, Germany and the Netherlands).

The recent Supreme Court judgment confirms the previous decision of the Barcelona Court of Appeal, which revoked the patent due to lack of inventive step, thus setting aside the first-instance decision by which the validity of the patent had been upheld.

First-instance decision

In July 2011 Accord Healthcare SLU and Sandoz Farmacéutica SA filed an action for the revocation in Spain of the EP'364 patent due to lack of inventive step.

In a July 9 2012 decision Barcelona Commercial Court No 2 dismissed the action, upholding AstraZeneca's main arguments as follows:

  • At the patent's priority date (May 31 1996) the skilled person would not have been motivated to develop a sustained release formulation of quetiapine. At that time there was no concluding evidence of the therapeutic efficacy of quetiapine as it had not yet been commercialised as a drug.
  • The chemical and physical properties of quetiapine (high water solubility, high first-step metabolism, high adherence to plasmatic proteins and insufficient occupation of D2 receptors) made it an unsuitable compound for sustained release formulation. Hence, the skilled person would have ruled out this solution.

Appeal decision

Accord and Sandoz appealed the first-instance judgment, alleging as follows:

  • At the priority date of the patent the skilled person was motivated to develop a sustained release formulation of quetiapine, as the specification of EP'364 itself explicitly acknowledged. The advantages of sustained release formulations were well known, including improvement of patient compliance, which was already desirable in the treatment of psychiatric disorders in general, and particularly in the treatment of schizophrenia.
  • During the court proceedings AstraZeneca provided no evidence regarding:
    • the alleged chemical and physical properties of quetiapine;
    • whether these properties were known to the skilled person at the priority date; and
    • why the abovementioned properties would have dissuaded the skilled person from developing a sustained release formulation of quetiapine.

Further, other than high water solubility, the alleged characteristics of quetiapine were not mentioned in the EP'364 patent.

After examining all the evidence, the Barcelona Court of Appeal found that all the EP'364 patent claims lacked inventive step, and declared the patent invalid.

In line with Accord and Sandoz's arguments, the appeal court first considered that at the priority date (May 31 1996) the skilled person would have been motivated to develop a sustained release formulation of quetiapine, as the specification of EP'364 acknowledged.

The appeal court also observed that there was no evidence that some of the chemical and physical properties of quetiapine alleged by AstraZeneca were actually known at the priority date. In any event, the court concluded that these properties would not have dissuaded the skilled person from developing a sustained release formulation of quetiapine with a gelling agent.

Thus, the appeal court applied the so-called 'problem and solution approach', and found that the EP'364 patent lacked inventive step.

Supreme Court decision

AstraZeneca appealed the appeal decision to the Supreme Court on two grounds: a procedural infringement and a substantive infringement of law and jurisprudence.

The alleged procedural infringement related to the motivation of the decision and the assessment of the evidence deployed in the proceedings. The Supreme Court dismissed AstraZeneca's arguments, finding that the appeal judgment was not illogical, but duly motivated. In particular, the Supreme Court held that the Barcelona Court of Appeal had properly applied the problem and solution approach to judge the inventive step. In addition, the Supreme Court concluded that the assessment of the evidence made by the appeal court was reasonable, and thus did not require review.

The Supreme Court also dismissed the substantive infringement of law and jurisprudence alleged by AstraZeneca. In this regard, the Supreme Court explained that the inventive step analysis performed by the appeal court did not violate any rule on how to combine prior art documents or the definition of a 'skilled person'.

Comment

The Supreme Court's decision is final and cannot be further appealed. Therefore, the EP'364 patent has been definitively revoked in Spain. Parallel litigations led to the same result in other European countries. For instance:

  • the UK Patent Court revoked the patent at first instance (2012) and on appeal (2013);
  • the German Federal Patent Court held the patent invalid in a decision (2012), later confirmed by the Federal Court of Justice (2015); and
  • the Court of Appeal of The Hague revoked the patent in the Netherlands (2014).

For further information on this topic please contact Miguel Gil at Grau & Angulo by telephone (+34 91 353 36 77) or email (m.gil@gba-ip.com). The Grau & Angulo website can be accessed at www.gba-ip.com.

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