SPC protection for second medical uses post-Brexit - UK Court of Appeal clarifies test

The Court of Appeal has clarified that Brexit has not changed the test to determine whether supplementary protection certificate (SPC) protection is available for second medical use products. In Merck Serono the Court of Appeal upheld the Hearing Officer’s decision to refuse an SPC application based on a patent for the use of a product to treat multiple sclerosis (MS) where the product contained the same active ingredient as earlier marketing authorisations, for the treatment of a different disease. 

Factual background

In 2018, Merck Serono applied for an SPC for cladribine, relying on (i) a patent relating to the use of cladribine for treating MS; and (ii) a marketing authorisation (MA) for Mavenclad for the treatment of MS, containing cladribine as an active ingredient. The Hearing Officer refused the application under Article 3(d) of Regulation (EC) No. 469/2009 (SPC Regulation) as there were already two existing MAs for products containing cladribine as an active ingredient (for the treatment of hairy cell leukaemia).

Legal background and issue

Article 3(d) SPC Regulation requires that the SPC application must be based on the first authorisation to place the active ingredient on the market. The assimilated version of the SPC Regulation that applies in the UK post-Brexit is the same in substance. Early CJEU case law adopted a literal interpretation of the provision, dismissing applications based on marketing authorisations for new uses of the active ingredient (Pharmacia Italia C-31/03, Yissum C-202/05). In response to a reference from the English Court of Appeal, the CJEU departed from its restrictive literal interpretation in Neurim (C-130/11), on the basis that a fundamental objective of the SPC Regulation is to ensure sufficient protection to encourage pharmaceutical research and that the travaux préparatoires (Explanatory Memorandum COM (90) 101 final) supported the idea of giving SPCs for patents on new therapeutic uses of known products. The CJEU in Neurim ruled that therapeutic use could play a role in the analysis of whether or not the active ingredient in the product had already been the subject of a marketing authorisation. Neurim was the subject of much criticism for the uncertainty it created in the interpretation of the relevant provisions of the SPC Regulation and the resulting lack of harmonisation by national patent offices and ultimately the CJEU returned to its more narrow, pre-Neurim interpretation of Article 3(d) in Santen (C-673/18), ruling that:

 “a marketing authorisation cannot be considered to be the first marketing authorisation … where it covers a new therapeutic application of an active ingredient… and that active ingredient … has already been the subject of a marketing authorisation for a different therapeutic application”.

Application to the facts

The Court of Appeal had already decided to follow Santen over Neurim in a decision last year (Newron Pharmaceuticals v The Comptroller [2024] EWCA Civ 128), albeit on a different set of facts and considering Article 3(b). However, it had decided Santen was correctly decided. The Court therefore considered that it was bound by Newron to apply Santen. Indeed paragraph 4(2) European Union (Withdrawal) Act 2018 (Relevant Court) (Retained EU Case Law) Regulations (SI 2020/1525) provides that :

(2) A relevant court is bound by retained EU case law so far as there is post-transition case law which modifies or applies that retained EU case law and which is binding on the relevant court.

Even if it was not bound by Newron, Lewison LJ considered that it would not have been appropriate to depart from Santen under domestic rules of precedent. The judge summarised the case law regarding the situations when the Court of Appeal may depart from an earlier decision. While Lewison LJ acknowledged that the power to depart should be sparingly used, the judge noted that criticism by academics, judges or practitioners, the interpretation of international application in other jurisdictions, a change of circumstances since the earlier decision and a finding that an earlier decision defeats the purpose of a provision were all factors to take account in the assessment of whether or not to depart from an earlier decision. Few, if any of these factors applied in the Merck Serono case and so even if the Court had not been bound by Newron, it would not have been appropriate to depart from the CJEU’s decision in Santen.

How likely are UK courts willingly depart from established EU case law?

Arnold LJ noted in his judgment that the assimilated version of the SPC Regulation had not been amended in the course of Brexit, indicating that the will of Parliament remains that SPC legislation should continue to be harmonised with the EU. Therefore the UK court should interpret the legislation in line with the CJEU unless convinced the CJEU’s interpretation is wrong. This is an interesting insight into how willing higher courts in the UK may be to depart from EU case law predating Brexit's implementation when it comes to interpreting assimilated versions of EU instruments which have not in substance been amended. We anticipate more willingness to depart in cases where CJEU case law has been inconsistent or unpredictable in its interpretation of an EU instrument. 

Merck Serono v The Comptroller-General of Patents, Designs, and Trade Marks [2025] EWCA Civ 45