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Construction of ‘’Swiss’’ medical use claims
In Ranbaxy (UK) Ltd v AstraZeneca AB, the England and Wales High Court
considered the scope of “Swiss” medical use claims. This important decision
clarifies how these types of claims can be infringed.
Background: “Swiss” Claims
The European Patent Convention (EPC) expressly excludes methods of treatment from
being patentable. The reason for this is that healthcare professionals should not be
prevented by patents from treating patients. This exclusion is a major difference between
the European and U.S. patent systems.
New and inventive pharmaceuticals are patentable, provided they are novel and inventive
in their own right. Under the original EPC, the first medical use of a known compound is
also patentable, using a claim worded “Compound X for use in therapy.”. However the
original EPC only included the first medical use under this provision.
An early decision (G5/83) of the Enlarged Board of Appeal of the European Patent Office
(EPO) considered the claim form that might protect a further inventive therapeutic use of a
compound. It decided that the wording “Compound X for the manufacture of a
medicament for [the therapy]” would be valid. This is known as a “Swiss” claim, and
under the original EPC was used to patent a second medical use of a known
pharmaceutical.
The Claims
AstraZeneca owned a patent (EP1020461) which contained a “Swiss” claim to the use of
high purity magnesium esomeprazole for the inhibition of gastric acid secretion.
Proposed Importation
AstraZeneca was the only supplier of esomeprazole in the UK. Ranbaxy sought a
declaration that their generic product for the inhibition of gastric acid secretion would not
infringe the patent.
Ranbaxy’s product was to be imported into the UK. Neither side disputed that one of the
starting materials for the product was magnesium omeprazole with the claimed purity, or
that Ranbaxy’s final product (which it wanted to import into the UK) did not have the
claimed purity.

Construction of ‘’Swiss’’ medical use claims
Construction of “Swiss” claims

The court considered whether, either:
 Ranbaxy infringed, because their product was the direct product of a process which
 magnesium esomeprazole to make a medicament; or,  Ranbaxy did not infringe, because their product did not contain magnesium
The UK courts construe a patent claim by asking what meaning a skilled person would
have given to the terms in the claim, in the context of the patent.
The High Court judge decided that the teaching of the whole specification was to the
production of pure esomeprazole and its’ use in the inhibiting gastric acid secretion. As a
result, the judge interpreted the “Swiss” of claim as directed to the use of the pure
magnesium esomeprazole in the manufacture of a medicament, which medicament
contains the active ingredient at that level of purity.
The High Court declared that Ranbaxy would not infringe the “Swiss” claim, because the
product it intended to import did not have the claimed purity.
This case provides interesting guidance on the scope of “Swiss” medical use claims
in the UK. The courts will construe these claims as covering a medicament,
containing the claimed active ingredient, packaged for use in the claimed therapy.
The EPC 2000 came into force in 2007. This updated European Patent Convention
allows the previous “first medical use” claim form to protect any subsequent
medical uses of a known pharmaceutical. We recently reported anwhich stated that “Swiss” claims are redundant under EPC 2000. We wait
to see if the UK court interprets “Swiss” claims and the new “medical use” claims
as having the same scope.

Source: http://forresters.co.uk/media/179586/ranbaxy_v_astrazeneca.pdf