[author: David Brown*]

The final decision of the Court of Appeal in the Lyrica® litigation was handed down on 13 October 2016.  This litigation, relating to the painkiller pregabalin marketed by Warner-Lambert for the treatment of pain under the name Lyrica®, has been keenly followed as the first detailed analysis of infringement of "second medical use" patents by generically available medicines.  In Europe, generically available medicines can be marketed without an explicit statement of potential uses that are still under patent protection ("skinny" labelling).  The use of pregabalin to treat pain is currently protected by a Warner-Lamber patent, and Actavis's drug, Lecaent®, is marketed with labelling that does not refer to pain.

The Court of Appeal decided that the patent was invalid on the technical ground that "pain" was not a single disease and so the claim was not adequately supported by the relatively limited data in the patent, relating only to peripheral neuropathic pain.  Furthermore, the Court held that Warner-Lambert had not requested appropriate conditional amendment of the patent early enough, and therefore could not maintain the patent in the limited scope of peripheral neuropathic pain.  In these findings, the Court upheld the decision of the Patents Court, handed down on 10 September 2015.

As a result of the invalidity of the patent, Lecaent® was found to be not an infringing product.  The Court of Appeal, however, also provided detailed obiter comments on the circumstances in which a "second medical use" patent may in principle be infringed by a generically available medicine marketed with skinny labelling.  The Court stated (paragraph 216):

"... it is only essential [for infringement] that the [generic] manufacturer is able to foresee that there will be intentional use [of the generic product] for the new medical indication.  Intentional use is to be distinguished from use where the drug is prescribed for a different indication and, without it in any sense being the intention of the treatment, a pain condition is in fact treated."

This "foreseeability" test is a factual test.  If intentional use for the in-patent condition is foreseeable, then it is incumbent on the generic manufacturer to take all reasonable steps to mitigate the risk, taking into account the ways in which the intentional use by the patient might be facilitated (e.g., prescribing practices of doctors; national dispensing guidelines to pharmacists; individual dispensing practices of pharmacists).  The Court stated (paragraphs 207 and 208):

"... [W]hat is sufficient to negative the existence of intention?  In my judgment the absence of the patented condition from the label cannot conceivably be sufficient to negative the intention.  Mr Speck [counsel for Actavis] recognised that there could be objective factual circumstances where the absence of a label identifying the patented indication did not negative intention, for example a manufacturer who proposes to sell far more of the drug than the market for the non-patented indication could bear.

Viewed in this way I think the answer becomes clear.  The intention will be negatived where the manufacturer has taken all reasonable steps within his power to prevent the consequences occurring.  In such circumstances his true objective is a lawful one, and one would be entitled to say that the foreseen consequences were not intended, but were an unintended incident of his otherwise lawful activity."

This important decision establishes that the burden is largely on the generic manufacturers to mitigate the risks of their products being intentionally taken by patients for an in-patent treatment.

The extent to which the prescribing practices of doctors, National Health Service dispensing guidelines to pharmacists and the individual dispensing practices of pharmacists will need to be refined to assist the generic manufacturers in this endeavour will no doubt be explored in the future, as the healthcare system in the UK adapts to this new guidance from the Court of Appeal.

Importantly also, the decision establishes a relatively patentee-friendly regime for the UK enforcement of second medical use patents.  As discussed in the decision (paragraphs 190 to 201),a range of approaches is found in Europe, with the German courts taking the view that a generic manufacturer will not infringe unless it positively recites the patented use on its packaging.

We understand that permission to appeal to the Supreme Court is being sought.

Warner-Lambert Company, LLC v Generics (UK) Ltd & Others [2016] EWCA Civ 1006

• Mr. Brown is a Partner with Haseltine Lake LLP.

This article was reprinted with permission from Haseltine Lake LLP.  The article was originally published in the 21 November 2016 issue of Haseltine Lake's Chemistry and Life Sciences Newsletter.