Supreme Court Rules Dosage Regime Patent Obvious

Anna L Hatt | April 2019

This recent Supreme Court decision relates to obviousness of a dosage regime patent.  The case raised two principal questions.  The first relates to how the obviousness test applies to a dosage patent and the second concerns whether the Court of Appeal was entitled to reverse the first instance judgment on that question in the circumstances of this case. 

The appeal was dismissed and the patent revoked for obviousness.  The lead judgment was given by Lord Hodge, with the other judges agreeing.  The case affirms the existing approach of the lower courts to the question of inventive step in both the UK courts and in the jurisprudence of the EPO.

The patent

European Patent (UK) No.  1173181 was owned by ICOS and exclusively licensed to Lilly.   The patent related to the use of a dosage regime of tadalafil for male erectile dysfunction.

Actavis had applied to revoke the patent on various grounds, including obviousness, and Lilly had counterclaimed for infringement.   The patent was found not obvious at first instance on the basis that a 25 mg/day dose of tadalafil was obvious from a prior art document Daugan, but that the claimed 5 mg/day dose was not.   This conclusion was overturned by the Court of Appeal on the basis that the skilled team would have extended dosage response trials down to a 5 mg/day dose.  

The decision

Lord Hodge agreed with the Court of Appeal, summarising his reasoning as follows:

 

The task which the notional skilled team would undertake was that of implementing Daugan.  The target of the skilled team would be to ascertain the appropriate dose, which would usually be the lowest effective dose.  The skilled team would know of that target from the outset of its research.  The pre-clinical and clinical tests involved familiar and routine procedures and normally progressed to the discovery of the dose-response relationship in Phase IIb.  In this case the trial judge’s findings of what would have been the sequence of the tests, which did not depend upon hindsight, included the finding, which the evidence clearly justified, that the team, having found a therapeutic plateau, would be very likely to test lower doses and so come upon the dosage regime which is the subject matter of the patent… I am satisfied that the Court of Appeal was entitled to interfere with the trial judge’s assessment of obviousness and to hold that the 181 patent was invalid for lacking an inventive step.

Lord Hodge provided a non-exhaustive list of nine factors relevant to assessment of obviousness:

  1. Whether the invention was obvious to try with a reasonable prospect of success (referring to MedImmune Ltd v Novartis Pharmaceuticals UK Ltd [2012] EWCA Civ 1234)
  2. Whether the research was routine in nature
  3. The burden and cost of the research programme
  4. The necessity for and nature of value judgements by the skilled team in the course of research
  5. The existence of multiple paths for research (as an indicator of non-obviousness)
  6. The motive of the skilled person
  7. Whether the results of research were surprising
  8. Hindsight must not be used, but it may be obvious to take a series of steps
  9. “Bonus effect” i. e.  whether an invention has an added benefit but is obvious for another purpose

With regard to the first factor, Lord Hodge commented that:

I am not persuaded that, in the context of a dosage patent, it is necessary for the skilled team to identify in advance of the Phase IIb tests the specific dose which is the subject of the claim.  Were it otherwise, many, if not most, dosage regimes would be patentable, whether the results of the tests were surprising or not, simply because the precise doses which ultimately are specified in the claim may not be sufficiently foreseeable.  In my view, the MedImmune requirement is met if the step by step approach, without the benefit of hindsight, demonstrates that the skilled team would be very likely to pursue the tests to the point at which they would ascertain the product or process falling within the claims.

Lord Hodge confirmed that the Court of Appeal had been entitled to reverse the first instance judge’s decision:

I consider that the Court of Appeal was entitled to treat the judge’s failure to appreciate the logical consequences of the finding - that it was very likely that the skilled team would continue the testing - as an error of principle which allowed an appellate court to carry out its own evaluation.

Lilly argued that the patent was non-obvious because it allowed daily rather than on-demand dosing.   The judge disagreed, noting that the claims were not limited to daily dosing, and moreover that the possibility of daily dosing would have been discovered via the tests in an obvious manner.

Lord Hodge commented on the relationship between the UK and EPO approaches to obviousness, quoting extensively from the EPO Guidelines for Examination.   He stated that:

In relation to the second submission, that the Court of Appeal’s approach was in conflict with the EPO’s problem and solution approach, it is important to recall Jacob LJ’s words in Actavis v Novartis… that no-one has ever suggested that the problem-and-solution approach is the only way to go about considering obviousness.  Like the Windsurfing/Pozzoli approach, it provides a structured approach which may assist in avoiding the dangers of hindsight and may be more helpful in some cases than in others.  No formula should distract the court from the statutory question: Generics (UK) Ltd v Daiichi Pharmaceutical Co Ltd [2009] EWCA Civ 646[2009] RPC 23, para 17 per Jacob LJ…

I am not persuaded that the problem-and-solution approach would necessarily give a different answer from that of the Court of Appeal.  The closest prior art is the Daugan patent and the well-established procedures of pre-clinical and clinical testing.  The problem posed by Daugan was the identification of an appropriate dosage regime.  The EPO approach to assessing the obviousness of the claimed invention would then be to apply the “could-would approach”, which means asking not whether the skilled person could have carried out the invention, but whether he would have done so in the hope of solving the underlying technical problem or in the expectation of some improvement or advantage: T-2/83 OJ 1984 265 (Rider/Simethicone tablet), para 7; T-1014/07 (above) paras 7 and 8.  The tangible evidence which reveals why the skilled team would have been prompted to come upon the asserted invention [includes] (b) Dr Saoud’s evidence that it was a “no brainer” to go on with the tests.  The judge’s finding that the skilled team would not have had an expectation of effectiveness at a 5mg dose does not militate against the conclusion that the team would have investigated that dose in the course of a sequence of tests which had as its purpose the solution of the underlying technical problem, which the implementation of the Daugan patent entailed.

Lord Hodge also considered the relevance of judgments in parallel revocation proceedings in various EPC member states.   He commented that:

Because of the differences in the evidence led, the manner by which it is tested, and the differing findings to which that evidence gives rise, one may derive support from the approach to the question and methods of reasoning of other national courts but should never rely uncritically on the outcome.

There were several interveners in the proceedings, including trade associations, which asked for guidance on obviousness of dosage regime patents.   Lord Hodge replied as follows:

The UK BioIndustry Association asked for guidance on the relevance in the assessment of obviousness of (a) the reasonable expectation of success as a factor and (b) the problem-and-solution approach of the EPO.  It expressed concern that the judgment of the Court of Appeal might support the view that empirical research in the field of bioscience would not be seen as inventive in so far as the methods of research were well-established.  The IP Federation similarly expressed concern about a perceived risk that people might extrapolate from statements in the Court of Appeal’s judgments that the result of routine investigations cannot lead to a valid patent claim.  It expressed a particular concern about the breadth of the statement by Lewison LJ (in para 180): “in a case which involves routine pre-clinical and clinical trials, what would be undertaken as part of that routine is unlikely to be innovative”. . .  I do not construe the judgments of the Court of Appeal as supporting any general proposition that the product of well-established or routine enquiries cannot be inventive… there is no policy reason why a novel and inventive dosage regime should not be rewarded by a patent.  A fortiori, efficacious drugs discovered by research involving standard pre-clinical and clinical tests should be rewarded with a patent if they meet the statutory tests.