UK Supreme Court issues Warner-Lambert v Actavis ruling

The UK Supreme Court today dismissed Warner-Lambert’s appeal in its pregabalin patent dispute with Actavis, while clarifying the role of plausibility in the sufficiency of patent applications.

Today’s ruling in Warner-Lambert v Actavis saw the court dismiss Warner-Lambert’s appeal that its patent was sufficiently disclosed and upheld Actavis and Mylan's appeal that the disputed claims were not sufficient.

The case centres on the drug pregabalin, which has historically been used to treat anxiety disorder and epilepsy.

US pharmaceutical company Warner-Lambert (Pfizer) owns EU patent number 0,934,061, which covers a second medical use of pregabalin for the treatment of inflammatory pain and neuropathic pain. The drug is sold under the brand name Lyrica.

Two competitors, Actavis and Generics (trading as Mylan), applied to revoke the ‘061 patent on the grounds of insufficient disclosure in 2014. In response, Warner- Lambert claimed that the two companies infringe the claims 1 and 3 of the patent.

In September 2015, Mr Justice Arnold of the English High Court held that the patent’s claim for treating neuropathic pain (claim 3)—both peripheral and central—was only partially plausible and concluded that the patent was invalid.

Arnold found that there was sufficient disclosure in the specification to support the claim that pregabalin was effective in the treatment of inflammatory pain (claim 2) and peripheral neuropathic pain, but not central neuropathic pain.

Warner-Lambert applied to amend claim 3, limiting it to peripheral neuropathic pain, but the court found this to be an abuse of process.

Warner-Lambert appealed against the decision.

At the Supreme Court, Warner-Lambert argued that all claims were valid and that there wasn’t a role for plausibility in considering whether the skilled person reading the patent would be able to work the whole of the invention claimed.

In today’s decision, the court held by a majority (Lord Sumption, Lord Reed and Lord Briggs) that the patent’s disclosure supports the claims in relation to inflammatory pain, but not neuropathic pain. It concluded that claims 1 (for treating any type of pain) and 3 (for treating neuropathic pain) fail for insufficiency.

The Supreme Court’s approach requires the patentee to show that the specification must disclose some reason for supposing that the “implied assertion of efficacy” in the claim is true.

Lord Sumption, in delivering the majority judgment, said that this must be more than a “bare assertion” or “mere possibility” of therapeutic efficiency.

“The disclosure may be supplemented or explained by the common general knowledge of the skilled person. But it is not enough that the patentee can prove that the product can reasonably be expected to work in the designated use, if the skilled person would not derive this from the teaching of the patent,” added Sumption.

According to the court, this approach respects the principle that a patentee can’t claim a monopoly of a new use for an existing compound unless he makes and discloses a contribution to the art.

On construction, the Supreme Court unanimously agreed with the lower court that claim 1 extends to all pain and claim 3 to all neuropathic pain.

Finally, the Supreme Court concluded that if claims 1 and 3 had been valid, they would not have been infringed by Actavis, but the reasons for arriving at this result differed substantially between the justices.

Sumption and Lord Reed concluded that the only criterion for infringement is whether the product is presented as suitable for the uses which enjoy patent protection.

But Lord Briggs and Lord Hodge followed Arnold’s view, that the test for infringement is whether the alleged infringer subjectively intended to target the patent-protected market (Arnold found that the alleged infringers had not intended this).

Pfizer said it was disappointed by the ruling and that the decision would have a significant impact on incentives for innovation in public health.

“The period that a medicine is under patent is a critical phase in its lifecycle that fuels innovation – as science evolves and knowledge grows, patients increasingly benefit from ongoing research into new uses for existing medicines,” said Pfizer.

It added: “As situations such as these are expected to become more common, it’s important for patients that pharmaceutical companies are able to protect patents, including second medical use patents.”

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