Lessons for Discovery in Patent Cases – Teva v Boehringer.

BY: HEDIE MEKA PhD

In Teva Pharma Australia Pty Ltd v Boehringer Ingelheim Pharma GMBH & Co. KG [2019] FCA 625, generic pharmaceutical manufacturer Teva Pharma Australia (“Teva”) scored a significant victory in their bid to invalidate two patents to Boehringer. This decision provides a useful summary for discovery in patent cases.

Australian Patent Nos. 2008203057 (Capsule Patent) and 757008 (Powder Patent) broadly relate to preparations containing inhalable forms of tiotropium, as either capsules or an inhalable powder. The patents describe that the claimed preparations have increased stability over known forms of tiotropium-containing inhalable preparations. Tiotropium is used to treat conditions involving contraction and relaxation of muscles, including respiratory disorders. The specification of each patent particularly refers to use of tiotropium for the treatment of asthma and Chronic Obstructive Pulmonary Disease, where inhalable administration of tiotropium is desirable. Tiotropium is a highly effective active pharmaceutical substance and as such, requires significant dilution with excipients during formulation. Diluting tiotropium raises the potential for instability of the substance in the final product formulation, which in turn may give rise to heterogenous dosage and administration of the active substance. The invention as claimed in each of the patents addresses the stability issue in inhaled forms of tiotropium.

Teva allege that the claims of each patent lack an inventive step when compared with the prior art base as it existed before the priority date in light of common general knowledge alone. Boehringer filed a cross-claim that Teva’s proposed product (Braltus) would infringe the contended patents.

Teva applied to the Court for discovery of documents relating to the development of the invention as claimed. Teva sought discovery in respect of five categories of documents and were granted discovery for all but one category of document.

Under Australian practice, discovery is permitted by order of the Court if and only to the extent that discovery is necessary to promote the just resolution of the proceeding as quickly, inexpensively, and efficiently as possible. “Fishing expeditions” for documents are not permitted. If discovery is granted by the Court, discovery may take many forms. Standard discovery (documents directly relevant to the issues pleaded) or non-standard discovery (category of documents). The Court may also make order limiting access to confidential documents.

In the current proceedings, Moshinsky J adopted the approach taken by Beach J in BlueScope Steel Limited v Dongkuk Steel Mill Co Ltd [2017] FCA 1537 (“Bluescope”) to assess whether the documents were discoverable. In Bluescope, Beach J considered that the material needed to be relevant to the question being considered, and indeed “material as to what the inventor actually did or thought could not be said to be irrelevant to the question of obviousness, but that it only rose to the level of secondary significance” and would only permit discovery of “such a category that is targeted, proportionate and over a relatively tight time frame”.

Categories 1 and 3 were relevant to the question of the steps in the development of a tiotriopium dry powder formulation for a capsule, and the moisture-sensitivity thereof in respect of the Capsule Patent. The material covered all documents recording communications regarding the project by Boehringer employees, external consultants, and the capsule manufacturer (spanning June 1999 to June 2001), and all related laboratory notes and reports (spanning June 1999 to June 2002). Teva adduced evidence that a formulator would seek to minimise moisture in the formulation, including in the capsule, and that the formulator would contact capsule suppliers to obtain information about low-moisture capsules which were suitable for use, and test the capsules that were recommended. On this basis, the judge was satisfied that the material encompassed in Teva’s request was relevant, but of secondary significance only. Moreover, the requested was sufficiently targeted, proportionate, and covered a relatively tight time frame, and thus granted leave for discovery.

Teva presented similar arguments and evidence in support of discovery for category 4 and 5 documents (laboratory notes and reports, and protocols or standard operating procedures) relating to development of formulations of tiotropium with different grades or different particle sizes of lactose, during the period from October 1998 to October 2001 regarding the Powder document. Similarly, discovery was granted for category 4 and 5 documents.

Discovery of category 2 documents was rejected on the basis that this category was not sufficiently targeted since the scope of documents encompassed development of a dry powder formulation. Category 2 was considered to be too broad, and thus the application for discovery was denied.

Finally, the judge stressed that “Boehringer is only required to discover documents of which it is aware after a reasonable search and which are, or have been, in Boehringer’s control”, which speaks to the convenience issue when assessing whether or not to grant discovery in patent cases.

This decision is a useful summary of the considerations for discovery in patent cases. It remains to be seen how, and if, the material will play a role in the final outcome of this very interesting patent dispute.