The High Court has ordered limited discovery in a patent dispute over Truxima, a biosimilar of the Roche medicine MabThera, while refusing five broader categories of documents sought by the defendants.
In a judgment delivered on 4 May 2018, Mr Justice Max Barrett ruled on the defendants’ discovery application in infringement proceedings brought by Biogen Inc., F Hoffmann-La Roche AG and Genentech Inc. against Celltrion Inc., Celltrion Healthcare Hungary Kft. and two Mundipharma companies.
The plaintiffs allege that Truxima infringes two Irish patents concerning uses of rituximab. The defendants dispute the patents’ validity and have counterclaimed for their revocation, alleging added matter, lack of novelty and insufficiency. Those claims were background to this interlocutory application; the judgment did not determine infringement or patent validity.
The defendants sought 15 categories of documents. Most had been agreed, but the court had to decide categories 3 to 9 and 15(i). Applying the tests of relevance, necessity and proportionality, the judge refused categories 3, 4, 6, 7 and 8. These included broad requests for inventors’ research and records, material about the consideration of prior art, and documents concerning patent validity shared with experts or legal advisers. The requests covered periods as long as 22 years.
The judge said the long periods required explicit justification and that the defendants had not shown the broader requests were necessary and proportionate. He relied on the Court of Appeal’s approach in an earlier patent discovery case, including its treatment of inventor material as secondary evidence where no inventor was expected to testify. He also considered evidence from the plaintiffs’ solicitor about the scale, cost and practical difficulty of searches across old records and multiple storage systems.
Category 5 concerned documents relating to the decision to undertake a trial of rituximab for chronic lymphocytic leukaemia. The judge ordered discovery in that category, but limited the plaintiffs to a reasonable search of the kind contemplated by rule 31.7 of the Civil Procedure Rules of England and Wales. He found the defendants had not established relevance beyond the narrower scope that had been contemplated in the related UK proceedings, and imposed the search limit to meet relevance, necessity and proportionality.
For category 15(i), concerning the O’Brien study of rituximab in chronic lymphocytic leukaemia, the judge ordered discovery on the terms offered by the defendants. The judgment records that the plaintiffs had offered an electronic search of material previously disclosed in US proceedings using appropriate search terms; the defendants had not explained why that offer was insufficient.
The ruling concerns document discovery only. It does not resolve the underlying patent claims or counterclaim.