Specifying a therapeutic effect in a product claim may not be helpful in overcoming an objection of inventive step, according to a recent EPO Board of Appeal decision. In the case in question, GlaxoSmithKline had applied for a patent on vaccines against Human Papillomavirus (HPV). The EPO’s examining division had refused the application in February 2009 on the ground, in particular, of lack of inventive step under Article 56 EPC. GSK appealed the decision and the Board of Appeal’s decision was handed down in December 2014 (T 1493/09).

At appeal, claim 1 of the main request read:

A vaccine composition comprising VLPs [virus-like particles] containing L1 proteins or functional L1 protein derivatives from HPV16, HPV18, HPV 31 and HPV 45 genotypes wherein the immune response generated by the vaccine is at a level in which the protective effect of each VLP type is still seen and wherein the vaccine composition comprises an adjuvant which is an aluminium salt.

Meanwhile, claim 1 of the auxiliary request further specified “for use in the prevention or treatment of a disorder related to HPV infection”. Claim 1 of the auxiliary request therefore differed from claim 1 of the main request only by being a second medical use claim by specifying the therapeutic effect of the vaccine composition.

In applying the problem-solution approach for assessing inventive step of the claims, the Board of Appeal considered that the difference between claim 1 of the main request and the closest prior art (D8) was that the vaccine of claim 1 comprises VLPs containing L1 proteins from HPV serotypes 31 and 45. It was noted that the wording of claim 1 did not preclude the presence of further L1 proteins, such that a vaccine also comprising L1 VLPs from HPV serotypes 6 and 11 (as disclosed in D8) falls within the scope of claim 1 of the main request.

The Board of Appeal considered that the technical effect of this difference was that the vaccine composition of claim 1 provides protection against HPV serotypes 31 and 45 in addition to those present in the vaccine composition of D8. The Board of Appeal therefore held that the problem to be solved was the provision of an effective vaccine against HPV, especially providing broad protection against cervical cancer.

The Board of Appeal went on to hold that claim 1 of the main request lacked inventive step under Article 56 EPC over D8 alone, or in combination with D10.

The Board of Appeal then turned to the auxiliary request, in respect of which the applicant had argued that the second medical use claim format specifically requires the vaccine to be for use in the prevention or treatment of a disorder related to HPV infection. The applicant thus argued that this claim type sets a higher bar with respect to evidence of the efficacy of the vaccine. However, the Board considered that the wording of claim 1 of the main request already implied that the claimed composition is an effective vaccine for the treatment of HPV-related disorders, and that this effect had already been taken into account when evaluating the inventive step of the main request. Consequently, the Board held that the assessment of inventive step of claim 1 of the main request was applicable to claim 1 of the auxiliary request, and, therefore, that claim 1 of the auxiliary request also lacked inventive step under Article 56 EPC.

In conclusion, it appears that a change of claim category, from product to second medical use, may not always be helpful in overcoming an objection of lack of inventive step, although it remains useful for overcoming an objection of lack of novelty. In particular, it appears that, as the problem-solution approach of the EPO requires that the technical effect of a claimed invention is identified and considered, reciting a technical effect in a claim may add nothing to the claim for the purpose of inventive step. Thus, while specifying the technical effect may help draw the examining division’s attention to the problem solved, and may help to exclude interpretations of the claim for which the technical effect does not occur, practitioners should note that such an amendment may not always be successful in providing an inventive step.