Shionogi takes InterMune to US court, claiming unpaid EU royalties for Esbriet
This article was originally published in Scrip
Shionogi has lodged a legal action in the US against InterMune, claiming that the US firm has failed to pay due royalties on sales of the idiopathic pulmonary fibrosis (IPF) drug Esbriet (pirfenidone) in the EU.
The suit, filed in the US District Court for the Northern District of California in San Francisco, principally alleges a breach of the two firms' data-sharing agreement, which InterMune notes in an SEC filing governs "the exchange and use of certain documents and information relating to the parties' respective clinical trials of pirfenidone."
Shionogi stated that the agreement between the two firms had meant that "using Shionogi's clinical trials of pirfenidone in its Marketing Authorisation Application (MAA) to the European Medicines Agency (EMA), InterMune has obtained the MAA approval".
The complaint alleges that the subsequent failure to pay royalties to Shionogi on all net sales of Esbriet in the EU is in breach of the agreement, or if the US firm did not use the data in a way to trigger a royalty, it has an obligation to do so as a licensee, InterMune's SEC document notes.
The Japanese company is seeking unspecified monetary damages and a formal declaration from InterMune that it is obliged to pay royalties to Shionogi on all its sales of the drug in the EU. "InterMune strongly disagrees with Shionogi's claims and intends to defend its position vigorously," the Brisbane, California-based firm retorted.
The oral drug, developed originally by Marnac, had its first launch worldwide in Japan (as Pirespa) in 2008 through Shionogi, which also holds rights in South Korea and Taiwan. InterMune, which acquired all other worldwide rights in 2002, launched it for mild to moderate IPF in September last year, marking the availability of the first drug in Europe for the respiratory disease and also the first market entry for the firm.
Pirfenidone slows decline in lung function by inhibiting the synthesis of TGF-alpha and TGF-beta-1, which are involved in pulmonary inflammation and collagen deposition, and inhibiting p-38 gamma MAP kinase.
While it was launched in Germany last September (and is also approved in the non-EU countries Norway and Iceland), reimbursement decisions for Esbriet in several EU markets have been delayed, although InterMune expects to receive these later this year (scripintelligence.com, 9 April 2012). Sweden has just authorised its reimbursement.
InterMune reported EU Esbriet sales of $2.8 million in calendar 2011 and $4.9 million in the first three months of this year.
Neither company in the dispute refers to the specific data that were involved, but the publicly available EMA CHMP assessment report carries a table of clinical efficacy studies for pirfenidone in IPF. This includes one Shionogi Phase III study and a single Shionogi Phase II trial.
The royalty is payable territory-by-territory at 6% of net sales for the first and second calendar year following commercialisation, at 8% for the third and fourth year and 10% thereafter, expiring with the loss of respective market exclusivity.
Esbriet received a complete response letter from the US FDA in May 2010 that requested another efficacy study, and top-line results from the delayed Phase III ASCEND trial are currently expected in the first half of 2014.
Somewhat ironically, the US regulator had requested access to data from Shionogi's pivotal Japanese clinical trial, but InterMune said that obtaining the data would be difficult, despite its sharing arrangement, due to language and other restrictions.
The Shionogi study had also been criticised in some quarters because of a change in primary endpoint during the trial, missing data and a lack of patient-reported outcomes (scripintelligence.com, 5 May 2010).