Ranbaxy has received FDA final approval for its generic Valtrex on January 31, 2007 and subsequently has notified GlaxoSmithKline about its intention to market the generic Valtrex tablets in the US before expiry of the U.S. Patent No. 4,957,924 (the ‘924 patent) for which patent infringement lawsuit is pending with the district court. GlaxoSmithKline will apply to the court for a preliminary injunction prohibiting launch of Ranbaxy’s generic Valtrex pending completion of the lawsuit. Apart from Ranbaxy, Mylan also received FDA tentative approval for generic Valtrex following the expiration of ‘924 patent in 2009. Ranbaxy is the only generic manufacture to make Para IV certification for the ‘924 patent covering hydrochloride salt of L-valyl ester prodrug of acyclovir. Under the terms of agreement between the companies, previously approved by the court, if GSK applies for such an injunction within 45 days, Ranbaxy will not launch its product until the court either rules on the preliminary injunction or decides the pending court case. However, no trial date has yet been set for this litigation. Earlier in May 2003, GSK filed Para IV infringement lawsuit in the U.S. District Court of New Jersey against Ranbaxy alleging infringement of the ‘924 patent for Valtrex, generically known as Valacyclovir which will run patent protection till June 23, 2009.