GlaxoSmithKline Plc has filed a suit in a US court
seeking a preliminary injunction to stop Indian drug major
Ranbaxy Laboratories from launching a generic version
of Glaxo's Valtrex, a drug used for treatment of shingles
company will file the application a New Jersey federal
court to block Ranbaxy from selling the product, it said.
Indian company won US regulatory approval to market valacyclovir
hydrochloride tablets on February 1 but Glaxo has been
fighting Ranbaxy's plans since May 2003.
two had a prior agreement under which Ranbaxy would not
launch its product until the court either ruled on the
preliminary injunction or decided the pending court case
if Glaxo applied for an injunction within 45 days, according
to Glaxo. Valtrex, it said, is also protected by a basic
"composition of matter" patent which valid till
had received US Food and Drug Administration (FDA) approval
for its generic product on February 1 and had informed
Glaxo that it plans to market the product.
a statement, Glaxo said it had filed a patent infringement
suit in May 2003 against Ranbaxy contending that its generic
product would infringe Glaxo's basic ''composition of
matter'' patent for Valtrex which, the company said, expires
in June 2009.
said while several companies have applied for US approval
of generic Valacyclovir, Ranbaxy is the only manufacturer
to have made a direct challenge to its basic patent. Ranbaxy,
however, failed to comment.