On March 4 2013 Section 28 of the Madrid Court of Appeal confirmed that inventions consisting of the use of a known substance for the treatment of a known disease, where the novelty lies only in the dosage regime, can be patented provided that the novelty and inventiveness requirements are met. In assessing the fulfilment of these two requirements, the court annulled a patent held by Merck for the use of finasteride for the oral treatment of androgenic alopecia in dosages of between approximately 0.05 milligrams (mg) and 1mg.


In 2007 Actavis, AE Tiefenbacher and Industrial Farmacéutica Cantabria filed a nullity action against Merck before the Madrid courts, claiming the revocation of patent ES2.105.774 (EP724.444). This patent referred to a method for treating androgenic alopecia with 5-alpha-reductase inhibitors and, in particular, claimed the use of finasteride for the preparation of a medicament for oral administration wherein the dosage amount was between 0.05mg and 1mg.

In 2009 Merck filed an infringement and preliminary injunction claim against Actavis and Industrial Farmacéutica Cantabria before the Barcelona courts on the basis of patent ES2.105.774. Although initially granted, the preliminary injunction claim was rejected by the court, which considered that the patent failed to comply with the inventive step requirement. This decision was ultimately confirmed by Section 15 of the Barcelona Court of Appeal by a court order issued on January 24 2011.

On request by the parties, the nullity and infringement proceedings were consolidated before the Madrid courts. On February 16 2011 the court of first instance rejected the patent infringement claim, admitted the nullity claim and declared Merck's patent to be null and void. In its decision, the court relied on the previous decision issued by the Barcelona Court of Appeal and stated that "a dosage regime is patentable, provided certain requisites are met, among them the requisite of inventive step". In addressing compliance with this requirement, the court found that the dosage regimen that was claimed in the patent failed to provide any unexpected technical effect and, therefore, did not meet the inventive step requirement.

Merck appealed the decision.


On March 4 2013 the Madrid Court of Appeal confirmed that the use of finasteride for the treatment of androgenic alopecia had already been disclosed by Merck's previous patent EP285.382, and that oral administration was also covered by that patent. Therefore, the court considered that it was only the dosage regime that differentiated the contested patent from the prior art documents.

After analysing the different versions of Section 54 of the European Patent Convention and decisions issued by the European Patent Office in relation thereto,(1) the court stated that the "specific use" that is expressly mentioned in the new wording of Section 54 does not necessarily have to refer to the treatment of a different disease, but can also refer to a dosage regime. However, novelty and inventive step must be strictly analysed in order to avoid 'evergreening' practices (methods by which rights holders use the law and related regulatory processes to prolong their patent royalties, particularly with regard to 'blockbuster' drugs).

In this regard, when the dosage regime represents only a selection within the teachings already disclosed in the prior art, the requirements of selection patents must be met in order to comply with the novelty requirement. Similarly, the dosage regimen must provide a specific technical effect when compared with the prior art in order to meet the inventiveness requirement.

In the case at hand, the appeal court found that Merck's patent failed to meet the inventiveness requirement because the dosage regimen of between approximately 0.05mg and 1mg as claimed in the patent provided no specific technical effect. The effectiveness of low dosages of finasteride in the oral treatment of androgenic alopecia had already been disclosed, and the two prior art papers asserted by Merck as 'teaching away' evidences could not be considered as such. Those papers raised doubts about the way in which finasteride worked, but did not exclude its efficacy in the treatment of androgenic alopecia. The need to conduct further tests in order to find the specific lowest possible dosage that maintains the efficacy of the product was only part of the general good practice in the field.


The Madrid Court of Appeal has confirmed the relevance of decisions already issued by the European Patent Office with regard to dosage patents, despite the fact that they are not binding. This judgment confirms the patentability of dosage regimes provided that they always comply with the novelty and inventiveness requirements, which must be strictly assessed in order to avoid evergreening practices.

For further information on this topic please contact Beatriz Diaz de Escauriaza at Bird & Bird by telephone (+34 91 790 6000), fax (+34 91 790 6011) or email (beatriz.diaz.escauriaza@twobirds.com).


(1) G 5/83, T 4/98, T 1020/03, G2/08.

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