Janssen HIV Drug U.K. Patent Extension Case to Go to EU Top Court

By Peter Leung

Sandoz Ltd.’s lawsuit to clear the way for its generic version of the Prezista HIV drug will now go to the Court of Justice of the European Union.

The England and Wales Court of Appeal (Civil) Jan. 25 referred the dispute to the EU’s top court, to clarify how to determine whether a particular product is covered by a supplementary protection certificate (SPC), which extends the protection term for certain patent rights for drugs. SPCs are governed by EU law and are designed to make up for some of the patent protection term lost to the market approval process.

The CJEU’s decision will provide guidance on how to analyze whether an SPC actually covers the drug it is supposed to protect. Generic drug companies often attack the SPC as a way to clear the way for their own versions of the drug.

Johnson & Johnson, the parent of the patent owner Janssen Sciences Ireland UC, reported in 2017 $1.82 billion in worldwide sales of drugs with darunavir, the generic name for Prezista.

HIV Drug

Sandoz sued Janssen arguing that the SPC for Prezista actually doesn’t cover the product. Janssen’s SPC is based on its patent covering Prezista, but the analysis for whether a product is covered by an SPC is different from the test to determine if a product is covered by a patent.

The trial court sided with Janssen, saying that the SPC covered Prezista.

On appeal, Sandoz didn’t dispute that the drug is covered by the patent, but argued that EU law requires that SPCs describe the protected chemical more specifically. The SPC covering Prezista, which expires in February 2019, doesn’t meet that higher threshold, Sandoz said.

One complexity stems from how the patent was drafted. The patent claim didn’t specifically describe the structure of darunavir, but instead covered all variations of a disclosed chemical structure in a type of claim known as a Markush formula. According to Sandoz’s expert witness the patent claim covers trillions of possible chemical compounds.

Referral to EU Top Court

The Court of Appeal said that under its own interpretation of EU law, the SPC would protect Prezista, but there were several unanswered questions that must be referred to the CJEU before it could issue a definitive ruling.

The Court of Appeal said the test it favored would look at whether product covered by the SPC “embodies the core inventive advance of the basic patent.” Darunavir would be protected by the SPC under that approach, because a skilled person would immediately recognize that the patent claim describes darunavir, the active ingredient and the core of the invention, the court said.

However, it isn’t clear that approach is the correct one, the court said. Some CJEU cases require that the product protected by the SPC be “specified” or “identified.” In those cases, the Prezista SPC wouldn’t cover darunavir because the patent on which it is based doesn’t specifically disclose the active ingredient of the drug, the court said.

Lord Justice Christopher Floyd wrote the opinion, which Lord Justices Kim Lewison and David Kitchin joined. Fieldfisher LLP represented Sandoz, and Charlotte May and William Duncan were the barristers. Bristows LLP represented Janssen, and Thomas Mitcheson and Stuart Baran were the barristers.

The case is Sandoz Ltd. v. GD Searle LLC , [2018] EWCA Civ 49, EWCA (Civ) (U.K.), No. A3 2017 1483, 1/25/18 .

To contact the reporter on this story: Peter Leung in Washington at pleung@bloomberglaw.com

To contact the editor responsible for this story: Mike Wilczek at mwilczek@bloomberglaw.com

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