Lundbeck’s patents protecting their blockbuster Cipralex® have been subject to invalidation actions around the globe for already quite some years. Cipralex® is an antidepressant drug which contains as the active substance Escitalopram, the (S)-enantiomer of the racemic mixture (citalopram) marketed amongst others as Cipramil®.

Cipramil® was protected in the Netherlands by NL 192.451 C, filed 1977, and by SPC 970031 which expired in 2002. Lundbeck applied for a European patent application in 1989 for seeking patent protection of Cipralex®. This patent application was eventually granted as EP 347.066 B1 (expired in 2009). The corresponding SPC 300155 will expire in 2014. One could say that Lundbeck has had protection for the same drug for more than 35 years.

The validity of EP 347.066 B1 and SPC 300155 has been litigated in the Netherlands as from 2008. EP 347.066 B1 has two independent claims, i.e. claim 1 which is directed to the product Cipralex® per se, and claim 6 which is directed to a method for the stereoselective synthesis of Cipralex®.

The Dutch Patents Court decided in 2009 that claims 1 and 6 were not valid. The Dutch Patents Court held claim 1 novel but lacked inventive step (over established case law of the European Patent Office) and claim 6 obvious over Lundbeck’s US 4,650,884 in combination with the common general knowledge.

Lundbeck appealed. The Dutch Court of Appeal decided in January 2012 over the case and partly overruled the decision of the Dutch Patents Court. It was confirmed that claim 1 was novel but not inventive. However, claim 6 was considered unobvious and valid. As regards to the SPC, the Dutch Board of Appeal decided that it was valid in as far as it is based on the product as obtained by the process according to claim 6. Accordingly, Cipralex® made by other methods would not infringe the SPC.

Lundbeck filed an appeal at the Dutch Supreme Court in February 2012. The Oral Hearing took place in November. Friday 7 June 2013 the Supreme Court rendered its decision.

With respect of claim 1, the Supreme Court held that the Court of Appeal erred in deciding that escitalopram was novel but not inventive in view of citalopram.

An applicant who invents a novel and inventive method for preparing a new product is in principle entitled to have a patent directed to the method as well as to the product per se. If, however, there was another obvious method (or methods) available at the priority date by which the same product could have been obtained, the applicant would not be entitled to a product claim. According to the Supreme Court, in invalidity proceedings it is up to a third party to prove that such another obvious method was indeed available.

Before the Court of Appeal it was alleged that such another obvious method was available which was supported by experimental and expert evidence. However, the Court of Appeal did not assess this evidence. The Supreme Court ruled that the Court of Appeal should have considered this evidence and should have determined whether the allegation that this other method was available at the priority date was sufficiently substantiated. The case is now remitted to the Court of Appeal to decide on this issue. The Court of Appeal must therefore also decide whether the SPC is valid or not.

The Supreme Court did not criticise the findings of the Court of Appeal regarding claims 6 and 7.

NLO is representing its clients in collaboration with attorneys-at-law from BarentsKrans, The Hague.

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