US District Judge Sidney Stein in New York told both sides in the patent trial over the blockbuster blood thinner Plavix to submit their written arguments to him, Bloomberg News reported.By doing so the judge puts off a ruling for at least six weeks, the report said.Bristol-Myers Squibb and Sanofi-Aventis have spent the past four weeks in court trying to convince Stein that their patent on Plavix is valid, while Canadian generic drug maker Apotex has argued the patent is invalid and unenforceable.“Apotex is confident in its position,” Robert Silver, a lawyer for Apotex told Bloomberg News. “We believe there is evidence to support our defenses and look forward to a favorable decision.”Bolstering Sanofi-Aventis and Bristol-Myers-Squibb was an earlier ruling by Stein that Apotex hadn’t raised a “substantial question” of the validity of the patent. That ruling, which was upheld by an appeals court that specializes in US patent law, forced Apotex to stop shipping generic Plavix until the trial’s completion. “We obtained the preliminary injunction and we won the appeal,” Sanofi-Aventis CEO Gerard Le Fur said at a Feb. 13 press conference. “For these reasons, we remain very optimistic about these events surrounding the Plavix suit.”Stein told Apotex’s attorney’s to submit post-trial arguments within two weeks from last Friday. Bristol-Myers Squibb will have two weeks to present its argument, and Apotex will get two more weeks to prepare a rebuttal, according to the Bloomberg News report. Despite remaining upbeat, Bristol-Myers Squibb is readying itself for the loss of Plavix, CFO Andrew Bonfield told the Web site MarketWatch.com in a recent interview. “The challenge for us is to make sure that, if you look at the next couple of years, is to use some of the cash flow that comes out of Plavix to invest in our pipeline in order to drive growth beyond when the Plavix patent expires,” Bonfield told MarketWatch. According to the MarketWatch report, Bonfield admitted there would be no way for his company to make up for the loss of Plavix in the near-term, especially if the drug loses patent protection in an ongoing legal challenge this year. If upheld in court, Plavix’s patents are slated to expire in 2011. If the company agrees to conduct pediatric trials for the drug, the patent could be extended to 2012. However, if Apotex prevails, Plavix could lose patent protection by the end of the year. Plavix sales were $3.2 billion in the US for 2005, making it BMS’ top-selling product. The company’s total sales for 2005 were $19.2 billion. BMS sells Plavix in the US and Sanofi-Aventis markets it abroad. In 2006, US sales of Plavix slipped to $2.7 billion due to the temporary launch of a generic version of the drug by Apotex. A federal court forced Apotex to halt sales of its product after just a few weeks. The court however did not compel the company to recall its shipments of the generic drug. BMS’ financial picture “will look very different than it does today,” if BMS and Sanofi lose the case, Bonfield added.