Dutch court confirms limits on SPC protection for ‘second medical use’

The ruling concerns Merck's multiple sclerosis treatment Mavenclad and provides further confirmation of the continuing application of the Court of Justice of the European Union's (CJEU) decision in the Santen ruling in 2020. It also aligns with decisions reached in several other European countries.

Merck sought an SPC based on a patent covering the use of cladribine in the treatment of multiple sclerosis and the marketing authorisation granted for Mavenclad in 2017. An SPC allows a pharmaceutical company to effectively extend the period for which it can exercise monopoly rights over the sale of a medicinal product. However, cladribine had previously been authorised in medicines used to treat hairy cell leukaemia, including Leustatin and Litak.

The Dutch Patent Office rejected the application on the grounds that the Mavenclad authorisation was not the first marketing authorisation for the product within the meaning of Article 3(d) of the SPC Regulation.

Merck appealed to the District Court of The Hague, arguing that Mavenclad represented a new therapeutic use of cladribine that required extensive clinical development, including phase I, II, III and IV trials. The company argued that EU law should permit SPC protection for patented second medical uses and said that an earlier CJEU judgment, in the 2012 Neurim case, supported that interpretation.

The court dismissed the appeal. It found that, under the CJEU's ruling in the Santen case, a marketing authorisation granted for a new therapeutic use of a previously authorised active substance cannot qualify as the first marketing authorisation for the purposes of Article 3(d). Because cladribine had already been authorised in earlier medicines, the 2017 authorisation for Mavenclad could not support the grant of an SPC.

While the decision follows the established Santen approach, the wider debate is not yet settled. Earlier this year, the German Federal Patent Court referred questions to the CJEU on the application of the Santen doctrine where active ingredients are authorised for both veterinary and human medicinal products. In making the referral, the German court indicated that it considered the earlier Neurim approach the more persuasive interpretation where an active ingredient is first authorised for one category of medicinal product and later authorised for another.

The German referral has been described as a potential "Neurim reloaded" case and gives the CJEU an opportunity to revisit the relationship between the Neurim and Santen cases and to clarify whether, and if so in what circumstances, the reasoning in Neurim continues to have a role following Santen, according to experts at Pinsent Masons.

The District Court of The Hague declined to seek further guidance from the CJEU. It found Article 3(d) of the SPC Regulation sufficiently clear in light of its wording and existing case law. According to the court, existing case law, particularly Santen, permitted only one interpretation on the facts of the case. The court therefore rejected Merck's request for a preliminary reference, finding that neither SPCs granted for cladribine in some member states nor the German referral justified a different outcome.

Carly van der Beek, an expert in medicines regulation at Pinsent Masons, said: "This case demonstrates the continuing impact of Santen across Europe. By drawing a clear line under the broader approach taken in Neurim, the CJEU prioritised legal certainty and harmonisation. The Dutch court's ruling confirms that national courts continue to apply that approach strictly.”

"However, with fresh questions now pending before the CJEU on the relationship between Neurim and Santen, the boundaries of SPC protection for new uses of known active ingredients may remain a topic of debate."

Marthe Riewald, a life sciences patent litigation expert at Pinsent Masons, said: "The Dutch decision is consistent with the direction taken by courts and patent offices across Europe following Santen. That consistency is important for legal certainty and gives stakeholders greater predictability when assessing SPC rights and market entry opportunities across Europe."

Merck has pursued SPC protection for Mavenclad in several European countries, and the Dutch judgment follows refusals by patent authorities in some of those jurisdictions.

The decision is also relevant in the UK. In a post-Brexit case concerning the same product, the Court of Appeal considered for the first time whether it should depart from a CJEU ruling on SPCs. The court concluded that the case was not an appropriate vehicle for departing from Santen and refused Merck's application.

The ruling confirmed the UK's alignment with the CJEU's approach on this issue, although future divergence remains possible in an appropriate case. Separate proceedings involving cladribine are also continuing elsewhere in Europe.