Pregabalin - UK

Innovator: Warner - Lambert (Pfizer)

Generic Filer: Mylan & Actavis

Patent: EP0934061 (Click here to view UK's Patent)

Case No.: UKSC 2016/0197

Points to Ponder:

• Validity and Infringement.
• Plausibility.
• Second medical use.

Summary of Court of Appeal's Decision:

• Court of appeal found that patent was invalid, as the data in the patent was insufficient to render a claim covering neuropathic pain plausible (it would have been understood that pregabalin would only have been suitable to treat peripheral, not central, neuropathic pain). 
• Following finding Pfizer sought to narrow the claim to cover only treatment of peripheral neuropathic pain, but was not allowed to do so as the Court of Appeal held that this would be an abuse of process.

Claims of EP'061:

1. Use of (S)-3-(aminomethyl)-5-methylhexanoic acid or a pharmaceutically acceptable salt thereof for the preparation of a pharmaceutical composition for treating pain.
2. Use according to Claim 1 wherein the pain is inflammatory pain.
3. Use according to Claim 1 wherein the pain is neuropathic pain.
4. Use according to Claim 1 wherein the pain is cancer pain.
5. Use according to Claim I wherein the pain is postoperative pain.
6. Use according to Claim 1 wherein the pain is phantom limb pain.
7. Use according to Claim I wherein the pain is burn pain.
8. Use according to Claim I wherein the pain is gout pain.
9. Use according to Claim I wherein the pain is osteoarthritic pain.
10. Use according to Claim I wherein the pain is trigeminal neuralgia pain.
11. Use according to Claim I wherein the pain is acute herpetic and postherpetic pain.
12. Use according to Claim I wherein the pain is causalgia pain.
13. Use according to Claim I wherein the pain is idiopathic pain.
14. Use according to claim 1, wherein the pain is fibromyalgia pain.

Supreme Court Hearing Summary (12^th Feb, 2018 to 15^th Feb, 2018)

Pfizer’s Arguments on Validity of Patent:

• Patent was valid as there was no role for plausibility in considering whether the skilled person reading the patent would be able to work the whole of the invention claimed.
• If the Supreme Court thought that there was a role, Pfizer suggested that there should only be a low threshold that had to be met.

Actavis/Mylan’s Arguments on Validity of Patent:

• More stringent test should be applied.
• The skilled person in this field reading the patent with the common general knowledge in mind must have a reasonable prospect of success in establishing that pregabalin would treat neuropathic pain (including central neuropathic pain).
• They suggested that the patent must show a direct effect on the mechanism of the disease.

Pfizer’s Argument on Construction of Claims:

• One should not go looking for difficulties if, on the face of the language in the claim, there is no ambiguity.
• However, If there is real ambiguity, the "validating principle" that applies to contract construction should be applied, in which the Supreme Court seeks to uphold the claim (as a matter of policy).

Actavis/Mylan’s Argument on Construction of Claims:

• Suggested that the Supreme Court should interpret claims using ordinary English, with assistance of technical teaching drawn from the body of the patent.

Pfizer’s Arguments on Claims Amendment:

• The Court should have been allowed to amend its patent following the finding that the claim was invalid. This was for three reasons:

1. A patentee has a right to amend, which arises only once it has been made aware by the Supreme Court that its patent is invalid;
2. It was known following the judgment that a claim to treatment of peripheral pain would be valid and that relief should be granted in respect of the part of the claim that is valid and infringed;
3. It was disproportionate not to allow the amendment, as Pfizer could have paid Actavis’s/Mylan’s costs of dealing with the amendment at a future trial on the validity/infringement of the amended claim.

Actavis/Mylan’s Arguments on Claims Amendment:

• Countered all three arguments.

Points on Direct Infringement:

• Most options were presented by Pfizer on Direct Infringement.
• Earlier, The Court of Appeal proposed a test for direct infringement based on the manufacturer’s knowledge or reasonable foreseeability of the ultimate intended use for the patented indication, caveat that element of intention can be negatived where the manufacturer has taken all reasonable steps to prevent infringement.

Points on Indirect Infringement:

• The Court of Appeal: Had recapitulated that means for putting the invention into effect must be provided, but that there is no requirement for a downstream act of manufacture.
• Pfizer’s Argument: Test limited to the foreseeability of downstream use, but in closing fell back on the Court of Appeal’s “reasonable steps” approach.
• Actavis/Mylan’s Argument: There can only be infringement by the manufacturer where the manufacturer subjectively intends the product to be used for the patented indication, although they accepted as an alternative that objective intention may be sufficient, and as an ultimate fall back suggested an approach that simply required consulting the product label.

The Supreme Court on Judgment: 

• Confirmed that it will take some times to prepare the judgment.

*Case summary is based on different blogs and videos of hearing happened between 12th to 15th Feb, 2018. Please comment or e-mail if there is anything missing or required to change. Your valuable suggestions are always considered carefully for improvement of blog.