Bristol-Myers Squibb and Sanofi-Aventis went to court on Friday hoping to throw Apotex' generic version of their multi-billion-dollar clotbuster Plavix (clopidogrel) off the market, saying it would cause “irreparable injury” to their businesses. But the move came amid claims in the New York Times that a top executive from B-MS entered into a secret deal with Apotex as part of an earlier tie-up designed to prevent the launch of the Canadian firm's rival copy until after Plavix' patent expiry in 2011.

In a statement released by B-MS, it said an internal investigation had “not found any evidence of unlawful conduct by B-MS employees,” but added that it welcomed the Department of Justice's inquiry as to whether any staff were involved in unlawful or criminal conduct relating to the Plavix litigation. The filing, made by Apotex' lawyers, claims Chief Executive Peter Dolan's assistant Andrew Bodnar negotiated a separate deal that was not included in the revised version of its settlement, which would allow Apotex a six-month lead in the market before B-MS and Sanofi-Aventis launched their own generic version of Plavix, as well as a $60 million payment, reports the New York Times.

Earlier this year, B-MS and Sanofi-Aventis joined forces with Apotex under an agreement whereby the Canadian firm would agree not to launch a rival version before 2011 in return for an undisclosed sum. However, the companies were forced to revise this agreement after the Federal Trade Commission voiced its concerns over the anti-competitiveness of these 'sweetheart' deals. But this second agreement was also knocked back - triggering Apotex to launch its copycat drug and litigation against the Canadian firm to be reinstated - at the same time the Department of Justice launched an inquiry into the deal.

During the first day of the hearing on Friday, B-MS and Sanofi-Aventis' lawyer reportedly said the firms had lost billions in market value since the launch of Apotex' drug earlier that week. In the second quarter of 2006 alone, Plavix broke the $1 billion barrier, bringing $1.1 billion into B-MS' coffers.