Limited injunction in Australia on Pregabalin patent

Currently in Australia the approach to interlocutory injunctions in pharmaceutical patent litigation heavily favors maintaining the status quo.  This is highlighted by the fact that in recent years only one pharmaceutical case has seen an interlocutory injunction application refused.  This involved the cancer treatment drug, docetaxel (Interpharma Pty Ltd v Aventis Pharma SA [2011] FCA 32).  However, in a decision handed down Friday by Justice Griffiths (Warner-Lambert Company LLC v Apotex Pty Ltd [2014] FCA 241), a generic pharmaceutical company has been successful in getting a limited clearance to sell non-PBS products pending full trial.

Warner-Lambert sought an injunction against generic producers Apotex over the substance pregabalin.  The patent in question, AU714980 (the Pain Patent), claimed the use of pregabalin in the treatment of neuropathic pain.  Apotex listed a generic form of pregabalin for the adjunctive treatment of seizures.

Warner-Lambert argued that the market for adjunctive treatment of seizures is very small and pregabalin is rarely used in such treatment.  Warner-Lambert also suggested that if Apotex was able to secure the seizure market through heavy discounting, then they could also obtain access to the neuropathic pain market indirectly through this method.

Apotex successfully argued that since the Product Information listing for its product did not mention neuropathic pain, there was no infringement of the Pain Patent.  Apotex pointed out that the patent covering the pregabalin active and its use in the treatment of seizures, AU677008, was recently revoked by consent (See Apotex Pty. Ltd. v Northwestern University et. al. NSD 763/2013).  Apotex further argued that there are many other uses for pregabalin over seizure and pain treatments, including the treatment of anxiety and Parkinson’s disease, and this suggests that wider opportunities for profit exist over neuropathic pain.

Justice Griffiths granted interlocutory relief to Warner-Lambert with respect to pregabalin for the treatment of neuropathic pain.  However, the injunction was not extended to generic pregabalin indicated for seizures.

His Honour found that Warner-Lambert did not establish a prima facie case that Apotex’s supply of pregabalin for the treatment of seizures would infringe the Pain Patent.  Griffiths J further emphasized that even if this conclusion was found to be incorrect, he considered Warner-Lambert’s case to be weak (refer to [65], [69], [77], [82]).  It was further stated at [77] that ‘an assessment of the applicants’ damages in the event that Apotex is not restrained and the applicants ultimately succeed in establishing infringement of the Pain Patent, will be more straightforward than the alternative scenario of assessing Apotex’s damages if it is restrained and later seeks to enforce the undertaking as to damages if the applicants fail.’

Regarding public interest considerations, Griffiths J stated at [86] that ‘restraining the supply of the Apotex Products will deprive seizure patients of a choice of products and at a potentially cheaper price.’

It is not yet known whether there will be an appeal against this decision.

If you have any specific enquiries about the pregabalin case in Australia, please contact Paul Jones or Debra Tulloch.

This article was written by Dr Rosemary Manhire-Heath.