Following up on a report in our Spring edition of Patent issues (Bio Special Edition), Mr Justice Arnold’s judgement ( EWHC 2548 (Pat)) has now been published.
As a brief reminder of the background, this case concerns EP(UK) 0 934 061, a second medical use patent owned by Warner-Lambert for pregabalin in the treatment of pain (supplied under the trademark Lyrica), and its alleged infringement by Actavis, a generic manufacturer intending to supply the same drug (under the trademark Lecaent) for off-patent indications including generalised anxiety disorder and epilepsy. The issues surround the extent to which the generic manufacturer can supply the generic drug without care or regard to whether doctors and pharmacists prescribe it for the patented second use.
Firstly, the patent was found to be partially invalid, and in particular the claims relevant to the issue of infringement (i.e. claims 1 and 3 directed to the use for treating pain and neuropathic pain respectively) were found to be invalid for lack of sufficiency.
Applying the infringement test set out by the Court of Appeal, Arnold J also found that, even if claims 1 and 3 had been found to be valid, Actavis has not infringed these claims. The test is based on the interpretation of “for” in the Swiss claim as “suitable and intended for” and consequently requires that the manufacturer (generic manufacturer Actavis) knows or can reasonably foresee that some of his products will intentionally be used for the patented indication. This was found not to be the case and Arnold J granted a declaration that the manufacturer of Lecaent (Actavis), the wholesalers of Lecaent, the doctors prescribing Lecaent, the pharmacists dispensing Lecaent and the patients taking Lecaent do not infringe the patent.
Finally, Pfizer was found liable for making groundless threats of patent infringement proceedings.
Actavis seems to have won this battle but it is unlikely to be the end of this war. The 727-paragraph judgement has answered some questions and raised some more. Swiss claims have not been accepted by the EPO since 2011, but many granted patents were granted with Swiss claims, which can be litigated for many years to come and the issue may yet affect EPC 2000-type second medical use claims, since they include the crucial word “for”.
The general feeling is that, if there is a solution, then it will have to involve more than just changes to patent law. For the UK, it requires regulation by the Minister for Heath as to how doctors operating in the National Heath Service prescribe drugs that have patented second medical uses and whether they should be free to prescribe the generic drug or must stay within the “skinny label” indications. The expression “turkeys voting for Christmas” comes to mind. In the meantime, the uncertainty surrounding the scope and enforceability of Swiss claims is clearly unsatisfactory for all, including both innovation and generics companies.
When a generics company seeks a marketing authorisation for an off-patent drug and there is a patent still in force for a second (or subsequent) medical use, it is normal to identify the off-patent indications in the accompanying summary of product characteristics and the patient information leaflet. The patented indication is said to have been “carved out”. This is known as a “skinny label”.
Swiss Claims in Europe
For many years, patent offices in Europe and the courts have sought to grant and uphold patent protection for inventions which are made through the discovery of the new use of a known drug. Such second medical uses can be valuable and sometimes life-saving. Research into new uses of known compounds can be as expensive as discovery of new molecules. Discovery of new molecules is becoming more and more rare, whereas the range of known drugs and their potential for undiscovered effects has expanded.
There is no question of awarding the inventor of a new use absolute protection for the substance itself. Nor can a patent be granted for a method of treatment using the compound in question.
To circumvent these problems the Enlarged Board of Appeal of the European Patent Office has for many years granted claims for “the use of substance X for the preparation of a medicament (or pharmaceutical composition) for treating indication Y”. These are so-called “Swiss claims” because of their first use in the Swiss patent office. (See Eisai (Second medical indication)  OJ EPO 64.)
A problem with the Swiss form of claim is that it is a process claim targeted at the manufacturer. It is difficult to make a case for contributory infringement, because this would require a downstream infringer, and there is generally no-one downstream of the manufacturer who is using the substance for preparation of a medicament.
When the EPC was amended (renamed the “EPC 2000”) a different form of claim became permitted – simply “compound X for use in a method for treatment of disease Y.” (Other formulations are set out in Guideline G-VI, 7.1.2.) The EPO has stopped granting claims in the Swiss form after the EPO Enlarged Board of Appeal decision G 2/08, but claims already granted in that form continue to have effect.