On March 25 2009 the Fourth Commercial Court of Barcelona rejected Sanofi-Aventis Societé Anonyme, Sanofi Aventis SA and Bristol-Myers Squibb SA's preliminary injunction petition against various pharmaceutical laboratories for the alleged infringement of European Patent EP454511, validated in Spain as ES2119764.

EP454511 was filed by Sanofi on March 20 1991 (during the prohibition on patenting chemical and pharmaceutical products in Spain), and was granted by the European Patent Office on June 17 1998 (after the Agreement on Trade-Related Aspects of Intellectual Property Rights Agreement came into force in Spain).

In September 1997, with the patent still pending, Sanofi filed a special set of 22 process claims for Spain, which was subsequently validated in Spain.

Eight years after the patent was granted, Sanofi (like other patent holders) tried to add 19 product claims to the Spanish version of the patent (Claims 23 to 41).

Nevertheless, the Spanish Patent and Trademark Office (SPTO) rejected Sanofi's petition on the grounds that it is not possible to add new product claims to a patent once it has been granted. Consequently, it did not publish the revised translation of the patent. The SPTO's decision has been challenged by Sanofi before the Contentious Administrative Chamber of the Madrid High Court of Justice.

Thus, after the granting of various marketing approvals of Irbesartan's generic medicaments, Sanofi requested the adoption of preliminary measures against the holders of such approvals to prohibit the sale of the medicaments.

First, Sanofi alleged the infringement of product claims 23 to 29 and 36, despite the fact that these claims had been rejected and had not published by the SPTO.

Second, it alleged the infringement of claims 1 to 10 and 17 of the patent. Sanofi submitted no evidence on the defendants' manufacturing processes of Irbesartan, but simply invoked the reversal of the burden of proof according to Article 61.2 of the Patents Act.

With regard to Sanofi's first allegation, the courts had already pronounced in analogous cases (losartan, Atorvastatin and Quetiapine), rejecting the patent holders' actions because they were based on product claims which were ineffective and thus unenforceable against third parties, as they had not been published by the SPTO.

Following the last decision of the Barcelona Court of Appeal on October 2 2008 in the losartan Case, the court pronounced that product claims rejected by the SPTO could not be enforced against third parties as they must be published for them to be effective.

In light of the evidence provided on the patent's process claims, the court concluded that the defendants' Irbesartan-manufacturing processes fell outside the scope of protection of such process claims, literally, as well as under the doctrine of equivalents.

In the specific case of a group of defendants, the court verified that their Irbesartan manufacturing process is not only different from the one patented by Sanofi (eg, the starting compounds and chemical reactions), but also took into account that it is a new and inventive process, which has been granted a European Patent.

Therefore, the court rejected the preliminary injunction requested and ordered that the plaintiffs pay the costs of proceedings. As expected, Sanofi has filed an appeal against the court's decision.

For further information on this topic please contact Yvonne Sastre at Grau & Angulo by telephone (+34 93 202 34 56), by fax (+34 93 240 53 83) or by email ([email protected]).