Actavis UK Ltd v Merck & Co Inc

A Swiss-form patent claim may derive novelty from a new and inventive dosage regime or method of administration, even where the substance and its use against the same condition are known. Such a claim remains directed to manufacture where it does not in substance monopolise the clinician’s treatment of the patient.

The Court of Appeal may depart from its own patent-law precedent where settled jurisprudence of the European Patent Office is inconsistent with that precedent. This is a specialist and narrowly confined exception to the ordinary rule of precedent. Obviousness must be assessed using the skilled person’s knowledge and expectations at the priority date. An invention once thought worth trying may cease to be obvious after later scientific developments discourage the relevant research.

Merck owned a patent claiming the use of finasteride to manufacture an orally administered medicament for treating androgenic alopecia at a daily dosage of about 0.05 to 1.0 mg. Finasteride and its medicinal use were already known. Prior art had also proposed its use against androgenic alopecia, but at a dosage of at least 5 mg.

Warren J, in the Patents Court, held in [2007] EWHC 1311 (Ch) that claim 1 lacked novelty and was excluded as a method of treatment. He would, however, have rejected the challenge based on obviousness. Merck appealed the findings on novelty and patentability. Actavis cross-appealed on obviousness.

The central questions were whether a new dosage regime could confer novelty on a Swiss-form claim, whether that claim was in substance a method of treatment, whether earlier Court of Appeal authority prevented the court from following settled European Patent Office jurisprudence, and whether the claimed use was obvious at the priority date.

1. Appeal allowed and cross-appeal dismissed. A Swiss-form claim may be novel where the new therapeutic application consists of a new and inventive dosage regime or method of administration. The reasoning in Eisai, G5/83 [1985] OJ EPO 64, permits novelty to be derived from the new therapeutic use. There was no policy reason to reward research into treatment of a different disease while excluding valuable research into an improved treatment of the same disease. Such dosage claims will commonly fail for obviousness, because investigating dosage is ordinarily routine, but that does not remove their capacity for novelty.

2. The only applicable novelty inquiry was whether the prior art gave clear and unmistakable directions to do what the claim required. No prior publication had directed the use of finasteride to manufacture a medicament for androgenic alopecia at the claimed low dosage. The earlier Court of Appeal decision in Bristol-Myers Squibb v Baker Norton, [2001] RPC 1, did not contain a clear ratio that a dosage regime could never confer novelty. That case concerned a claim covering a dosage and administration regime already disclosed by the prior art.

3. The claim was not excluded as a method of treatment under article 52(4) of the European Patent Convention. It was directed in substance to the manufacturer preparing finasteride in specified dosages. It did not involve the extensive, patient-specific decisions by medical personnel which had caused the claim in Bristol-Myers Squibb to be characterised as a method of treatment.

4. The court recognised a specialist and narrowly limited exception to Young v Bristol Aeroplane Co, [1944] KB 718. The Court of Appeal is free, though not bound, to depart from the ratio of its own earlier decision where settled European Patent Office Board of Appeal jurisprudence on European patent law is inconsistent with it. The court will generally follow that settled view in order to promote the uniform interpretation intended by the European patent system.

5. The invention was not obvious. Obviousness had to be assessed from the skilled person’s perspective at the priority date. Recent scientific papers indicated that the type 2 enzyme inhibited by finasteride was undetectable in the balding scalp and that type 1 activity was the likely cause. The judge had ample evidence for finding that the expectation of success had fallen so low that the skilled person would not investigate finasteride for androgenic alopecia. No error of principle justified appellate interference.

6. The order revoking the patent was rescinded. The injunction was suspended unless Merck provided a cross-undertaking in damages should Actavis ultimately prevail. Time for seeking permission to appeal was extended until 28 days after the Enlarged Board’s decision on the reference in Kos Life Sciences.

1. Court of Appeal (Civil Division): In [2008] EWCA Civ 444, the court allowed Merck’s appeal, dismissed Actavis’s cross-appeal and rescinded the order revoking the patent.

2. High Court, Chancery Division (Patents Court): Warren J held in [2007] EWHC 1311 (Ch) that the patent was invalid for lack of novelty and because the claim was unpatentable as a method of treatment. He would have rejected the obviousness challenge.