Extending pharmaceutical patents in the United Kingdom

The contentious issue of patent extensions for pharmaceutical products has again come under the spotlight in a recent decision: Actavis v Boehringer. The decision signals that the UK courts are keen to extend pharmaceutical patents, even where the product is a combination of two known active ingredients, but the European Court of Justice (ECJ) will now have the final say.

What is an SPC?
A supplementary protection certificate (SPC) is a patent term extension for a patented drug that has received a marketing authorisation in Europe. The SPC is designed to compensate the patent holder when there is a significant delay between filing the patent and obtaining the marketing authorisation. As an SPC takes effect when the patent ends and the product is well known, it can provide substantial financial rewards for its owner.     

Actavis v Boehringer
Boehringer had a patent for Micardis (telmisartan), which treats hypertension. The patent expired in January 2012, but Boehringer’s SPC provides protection until December 2013. Boehringer developed follow-on product MicardisPlus, which contains telmisartan and hydrochlorothiazide (HCT). The UK Patent Office granted Boehringer a second SPC for MicardisPlus, which protects the product until January 2017. Both SPCs were based on the same patent, but the SPC for MicardisPlus will last longer as MicardisPlus took longer to be authorised.

Actavis wanted to launch a generic version of MicardisPlus, but was blocked by Boehringer’s second SPC. Therefore, Actavis asked the High Court to revoke the second SPC, in part because it did not correctly specify the active ingredients when granted. Actavis’s attacks illustrate the problems with this controversial aspect of SPC law.

When is a product specified in the claims?
In order to obtain an SPC, the patent must protect the product, which sounds like a simple test. However, the ECJ recently ruled that a product is protected only when it is 'specified' in the wording of the claims. The specified test has caused considerable uncertainty in the world of SPCs, as the ECJ did not explain how this test should work.

The Micardis product passed the specified test as the patent had a claim which mentioned the active ingredient (telmisartan) by its precise chemical name. The situation for MicardisPlus was more complex, because the patent as granted did not have a claim which specifically mentioned the combination of telmisartan and HCT. Conventionally, the patent still protected MicardisPlus, as a product containing telmisartan fell within the patent’s claims. However, as there was no claim that mentioned both telmisartan and HCT by name, Actavis argued that the second SPC was invalid because the patent’s claims did not specify this combination.

When is it allowable to amend?
When Boehringer applied for the SPC, the UK Patent Office suggested that the claims of the granted patent could be amended to include a claim to the combination of telmisartan and HCT. This post-grant amendment was allowed in the United Kingdom, as HCT was mentioned in the description. Actavis argued that because the amendment was made after the SPC application was filed, it was too late to fix the problem.

The judge decided that this issue required the ECJ to answer questions about how the specified test should work in practice. The judge asked the ECJ whether Boehringer needed to make the amendment at all, as the patent read with its description always specified telmisartan and HCT. If an amendment was required, he also asked whether it mattered when the amendment was made.  

What about duration?
Actavis argued that Boehringer should not be allowed a second SPC on the same patent – a live topic in several other SPC cases going to the ECJ. Actavis also argued that if the second SPC was allowed, its duration should be cut to stop 'evergreening' (the contentious practice of extending patent term for valuable pharmaceuticals). In particular, Actavis wanted both SPCs for Micardis and MicardisPlus to lapse simultaneously in December 2013.

New pro-SPC judge?
The judge, Colin Birss, has only just been appointed to the High Court and this was his first big SPC case. Birss’s comments in the case indicate he has a pro-patentee view of SPCs. He suggested that there is nothing wrong with a patentee amending a patent to improve its chances of getting an SPC, even if the amendment is made post-grant. He also suggested that there was no reason for the term of Boehringer’s second SPC to be cut. Therefore, it appears that the UK courts may continue to be a desirable venue for those enforcing an SPC.

Actavis v Boehringer highlights the chaotic world of SPC law in Europe. Pharmaceutical companies must hope that the ECJ will take a pro-patentee approach and allow Boehringer to keep its second SPC, following Birss’s suggestions. Generic companies will hope that the ECJ will strike down the second SPC or shorten its term. At the very least, the ECJ's answers might bring some clarity to this important area of law. For now, patentees could avoid these issues by ensuring that patent applications have claims that list any interesting combinations of products. Minor amendments such as that in this case might provide up to five valuable years of additional exclusivity in Europe.

This is an Insight article, written by a selected partner as part of IAM's co-published content. Read more on Insight

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