This is the end of the hard-fought UK battle between Neurim and Mylan. The Court of Appeal upheld Mr Justice Marcus Smith’s decision that the divisional patent was valid and infringed and so Mylan will now be subjected to a final injunction. The battle will continue in the European Patent Office (EPO), particularly as the parties agreed a cross-undertaking in damages in the event that the EPO revoke the patent (meaning Mylan dropped its application to stay the final injunction pending the EPO decision). However, a further challenge to the divisional patent, by Teva, will continue in the Patents Court. This decision demonstrates the difficulty of arguing a new point or elevating a minor point on appeal and is a further demonstration of why in the UK system it is so important to get the right expert and to produce robust evidence.
What are the practical implications of this case?
This decision brings to a close the long and hard-fought battle between Neurim and Mylan in the UK. Practitioners may be disappointed to hear that the parties agreed to a cross-undertaking in damages to compensate Mylan in the event the EPO revoke the divisional patent and so the point about whether a final injunction can be stayed pending an EPO opposition did not arise. The focus between these parties will therefore now shift to the EPO where opposition proceedings continue (with six opponents). However, the Patents Court recently refused Neurim’s preliminary injunction application against Teva (Neurim v Teva  EWHC 954 (Pat)) so they remain on the market; that challenge to the validity of Neurim’s divisional patent, on different grounds, will continue.
Mylan’s appeal concerned only one ground of invalidity—the so called ‘Lay Patient’ argument in which Mylan contended that, when properly understood, the data of the patent did not plausibly disclose the claimed effect of melatonin. The challenge to the decision of Marcus Smith J is very specific to the facts of the case and did not raise any new legal issues. However, it is a demonstration of the difficulty a party faces when:
- an issue is elevated to the sole issue on appeal when it was not articulated clearly, and was not the main case, at first instance, and
- the appellant’s expert did not come up to proof at trial
What was the background?
In December 2020, Marcus Smith J decided that patent EP (UK) 1 441 702 was valid and infringed by Mylan’s launch of a generic melatonin product (Neurim v Mylan  EWHC 3270 (Pat)). However, shortly thereafter the EPO decided the same patent was invalid on the basis of the
‘Lay Patient’ argument and the patent was revoked centrally. Despite this decision, the EPO examining division granted Neurim a divisional patent—EP 3 103 443. Neurim sued Mylan for patent infringement on the new divisional patent, which is not materially different to the parent patent found valid and infringed in the Patents Court. This led to a trial of preliminary issues
(Neurim v Mylan  EWHC 109 (Pat)) which allowed Mylan to continue with its single ground of invalidity against the divisional patent but only on the basis of the evidence at the trial of the parent patent.
In the parent patent trial, Marcus Smith J had heard evidence from two expert clinicians that specialised in sleep disorders. However, he was highly critical of the expert reports of Mylan’s expert and held that he was ‘not confident’ that he could ‘rely on Professor Morgan’s reports, save with a degree of caution and reserve that a judge would not normally attach to the report of an expert’. Accordingly, certain evidence that was relevant to the ‘Lay Patient’ argument was not accepted.
Marcus Smith J decided on the validity of the divisional patent following a short hearing at which the parties addressed him on the ‘Lay Patient’ argument. He maintained his view (see his March 2022 judgment, Neurim v Mylan  EWHC 519 (Pat)) that the divisional, like the parent patent, was valid and infringed.
What did the court decide?
This decision applies the criterion for plausibility stated by Lord Sumption in Warner-Lambert v Generics  UKSC 56. At first instance, the judge considered that the patent, in particular the clinical trial data of example 2 and 3, did plausibly disclose the effect claimed. Since this is an evaluative assessment by the judge, Mylan needed to identify an error of principle.
Mylan suggested five main reasons that the judge had not properly assessed the data of the patent considering the involvement of the ‘Lay Patient’ in the generation of the underlying data and instead focused on the viewpoint of the skilled person.
However, Lord Justice Arnold did not accept the arguments because, inter alia, he held that:
- it was right to focus on the purpose of the patent and the understanding of the skilled person in that context
- that it was appropriate to treat the disclosure with respect and ‘assume that the trials [...] were competently conducted’
- Neurim’s expert had given evidence in support of the patent’s data while the judge had been entitled to reject the evidence of Mylan’s expert, and
- Mylan’s best point (an internal contradiction in the patent—which the skilled person would need to resolve) had not been relied upon below and consequently had not been the subject of evidence. Mylan was therefore not entitled to rely upon it
Therefore, the appeal was dismissed, and the divisional patent was held valid and infringed.
- Court: Court of Appeal, Civil Division
- Judges: Lord Justice Newey, Lord Justice Arnold and Lord Justice Birss
- Date of judgment: 27 May 2022
This article was first published by LexisPSL on 17 June 2022.