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29 October 2014BiotechnologyAshley Roughton

HGS: where are we now with SPCs?

The dispute between Eli Lilly and Human Genome Sciences (HGS) over the patenting of the neutrokine-α protein and an antibody specific to it, belimumab, is continuing to the English Court of Appeal.

HGS was the owner of a patent which claimed the neutrokine-α protein and, in certain non-specific terms, the antibody. Eli Lilly failed to have HGS’ patent declared invalid. It then transpired that HGS might apply for a supplementary protection certificate (SPC) and that Eli Lilly might apply for a marketing authorisation for a product whose active ingredient is belimumab. In a pre-emptive strike, Eli Lilly sought a declaration that any application on the part of HGS for an SPC for belimumab would fail. The bases for such an argument were (i) that Eli Lilly would “own” its marketing authorisation and nobody else could rely upon it; and (ii) the patent was too vague and did not identify belimumab with enough specificity. The first argument was rejected by the judge as the SPC regulation is open about such things. The second point was of more interest.

The English Patents Court asked the Court of Justice of the European Union (CJEU) to explain what was meant by the word “protected”. Did it mean that a patent protected something even if it was not mentioned specifically in terms of its structure but was described in more oblique terms, such as being any antibody which has specificity to anything claimed in another claim?

The science

A cytokine is a signalling protein which enables communication between neutrophils (which are a certain kind of lymphocyte or phagocyte) and other cells in the body. One such cytokine is tumour necrosis factor (TNF), so called because when it was discovered it played a part in mediating tumour necrosis. It was later discovered that it has many more functions than that, but in immunology names stick so TNF it is. TNF can be a bad thing; it can, during cancer, cause severe weight loss that can end up killing the patient. A neutralising agent such as an antibody may, conversely, and in the correct clinical circumstances, be no bad thing.

The patent

The patent claimed a lookalike protein which was similar to TNF as well as, in claim 13 of the European patent, an antibody which bound to it or part of it. What was claimed was an antibody which bound specifically to a defined protein. There was no description of what the heavy chains, the light chains or the antigen binding sites, often called complementary determining regions (CDRs), of the antibodies might look like from a biochemical perspective. In one sense there might be no need—show me an antigen and I will show you an antibody.

The claim, not disputed by HGS, that there was no structural definition of the antibody, was correctly made. The real issue in the case was whether that claim was such as to render any resultant SPC invalid. The question therefore is: was a functional claim, a claim as to the required binding characteristics of the molecule, enough to generate protection in a patent sense for any antibody falling within claim 13? The answer is far from straightforward and relates to the policy objective of SPCs.

Interpreting the SPC regulation

A medicinal product is, in effect, any medicine: a substance or combination of substances for the prevention, treatment or diagnosis of disease. A product is narrower: it is anything which contains one or more of the active ingredients of a medicinal product. Marketing authorisations are granted for medicinal products and not products. An important principle in the SPC world is that the SPC protects a product and does not extend a patent. That means that the beneficiary of an SPC cannot, after expiry, sue all and sundry for infringement; he or she can only sue those who try to market that specific product.

Therefore, in some senses an SPC is narrower than its antecedent patent and in some senses it is wider as it “protects” a product that the patent may never have envisaged. However, this latter wide aspect of the SPC is of little comfort to the beneficiary of an SPC as an extended patent would have protected that product anyway. To put the debate in a slightly more colloquial way: the question is whether an SPC is a narrow form of patent extension or whether it is something different which feeds upon the antecedent patent but which has a life of its own, with its own rules of infringement and so on.

Put this way, one can see that one camp might suggest that an infringement test is the key and the other camp might say no: it is either the specific test in the SPC regulation or the specific subject matter test that is the key. Infringement may play a part in the specific subject matter test but it is only a part of the overall process.

In essence, the specific subject matter test requires the question “is the product specified in the claim?” to be answered. The controversy over what is meant by the word “specified” is of some significance. The operative word which cries out for understanding was the word “protected” as in a patent which “protects” a product.

"An important principle in the SPC world is that the SPC protects a product and does not extend a patent. That means that the beneficiary of an SPC cannot, after expiry, sue all and sundry for infringement."

In a straightforward scenario, a medicinal product may contain a number of ingredients, such as stabilisers, colourants, excipients (whether as bulking or facilitating agents) and, importantly, the active ingredient itself. And one question which may arise is: “How is that active ingredient defined?” There is nothing in the SPC regulation that says whether a structural formulation or a functional description will do, as there is nothing in UK domestic law which requires a claim to be structure-orientated.

The CJEU

Justice Warren referred the question to the CJEU, asking whether there was any steadfast requirement to a structural claim. The CJEU answered this question in two parts. In the first part of the answer, on whether the use of a functional definition may alone be sufficient in a patent claim, it said: “Article 3(a) of [the SPC] regulation... does not, in principle, preclude an active ingredient [being defined by reference to its function if] it is possible to reach the... conclusion on the basis [that]... those claims, [properly construed]... relate, implicitly but necessarily and specifically, to the active ingredient in question.”

So the controversy moved from a construction of the word “protected” to “relate”, but even then the answer was lucid enough to give the referring court sufficient guidance.

The second part of the answer, that addresses whether different parties could apply for marketing authorisations on the one hand and SPCs on the other, is more problematic and, it is believed, is what fuelled Eli Lilly’s contention that the CJEU had found in its favour when it said:

“In the light of the objective of [the SPC] regulation… the refusal of an SPC application for an active ingredient which is not specifically referred to... [in] a patent... [or] relied [up]on in support of such an application may be justified—in circumstances such as those in the main proceedings and as observed by Eli Lilly—where the... patent [proprietor] has failed to take any steps to carry out more in-depth research and identify his invention specifically, [where, as a result,]... it [is] possible to ascertain clearly the active ingredient… In such a situation, if an SPC were granted to the patent [proprietor]..., even though—since he was not the holder of the [authorisation]... granted for the medicinal product developed from the specifications of the... patent—the... patent [proprietor]... had not made any investment in research relating to that aspect of his original invention, [then] that would undermine the objective of [the SPC] regulation..., as referred to in recital 4 in the preamble thereto.”

What the CJEU said was this: that an SPC application will be refused where the active ingredient is not specifically referred to in the antecedent patent but only if the patent proprietor has failed to take any steps to carry out more in-depth research and identify his invention specifically so that the active ingredient can be ascertained clearly.

If, as the CJEU appears to say, the research expenditure which the SPC system is designed to protect was not carried out by the patent proprietor then why (it asks rhetorically) should the proprietor get a free benefit? Antibody and vaccine claims are routinely added on without any additional work.

However, Justice Warren did explain his position in some detail—that the SPC, if applied for, would have been validly granted—by saying that the research expenditure issue was one for the national court to examine and he ascertained that HGS did indeed carry out the necessary research which was sufficient and of sufficient detail to warrant protection by the SPC system.

Ashley Roughton is a barrister and co-author of The Modern Law of Patents, now running into a third edition. He can be contacted at: ashley@roughton.net