BioWorld International Correspondent
SYDNEY, Australia - Court documents lodged with the Supreme Court in Melbourne state that GlaxoSmithKline plc virtually abandoned marketing the flu drug Relenza two flu seasons after its launch, but had good reasons.
Lodged with the court in defense of claims by Melbourne-based Biota Holdings Ltd., which owned the key technology used in the drug, the statement said that in September 2001 the pharmaceutical giant decided to "minimize further promotional expenditure on Relenza."
The company also decided to get the U.S. FDA to agree not to undertake any of the Phase IV commitment studies that had not already been started.
Earlier, in May 2000, GSK's agents withdrew an application for the approval of Relenza by the Swedish Medical Products Agency. If the MPA had approved it, the other EU countries would have followed suit.
Biota is suing London-based GSK over the failure of the product for an amount unspecified but believed to be well in excess of A$100 million (US$76 million).
In its own statement of claim lodged with the Supreme Court in Melbourne in May of last year, Biota alleged that the product failure is due to GSK not pursuing alternative or improved inhalation systems for Relenza, withdrawing support for post-approval clinical studies designed to expand the product's use, and withdrawing promotion after the product's launch.
As a result, Biota alleged, after initially capturing close to 50 percent of the emerging global market for the new broad-spectrum flu drugs called neuraminidase inhibitors (NAI), Relenza's share of the market, estimated to be worth A$500 million a year, plummeted to 3 percent.
Rival product Tamiflu, marketed by F. Hoffmann La-Roche Ltd., which is a pill instead of an inhaled spray, became the market leader.
As is usual in Australia, where the rules for what is said in the press about court cases are stricter than in the U.S., neither side would comment beyond court documents.
But in those documents GSK had plenty to say, alleging that the decision to abandon Relenza was made for commercial reasons, including that sales of Relenza were very small and much smaller than competitor Tamiflu "despite significant promotional expenditure on Relenza in the two seasons after its launch." As a result, large amounts of unsold Relenza stock had been returned in 2001.
The court documents stated that feedback from physicians indicated they considered the two drugs to be similar in effect but that there was a "perception" of a side effect called brochospasm. In addition, Relenza needed an inhaler that required training for use.
Tamiflu also had an advantage of being approved for use in younger children. GSK and Biota have been ordered to try arbitration and there is no indication about when or if the matter might reach court.