The deal not only provides Sanofi with €453 million in cash to add to its takeover fund, but could also fend off regulatory obstacles to the acquisition.
The two products - Arixtra (fondaparinux sodium) and Fraxiparine (nadroparin calcium) - are both antithrombotics. Aventis' top-selling drug is an antithrombotic called Lovenox (enoxaparin), and Sanofi has sidestepped the risk that it may be forced to divest the drugs on antitrust grounds.
Fraxiparine, which like Lovenox is a low-molecular weight heparin product, achieved sales of €319 million in 2003, while turnover for Arixtra, a synthetic factor Xa inhibitor, reached €24 million. Lovenox sales were €1.66 billion last year.
The sale is conditional on Sanofi being successful in its bid for Aventis; the latter is less than enamoured with Sanofi's attentions and has said it favours a merger with Switzerland's Novartis. Under the terms of the agreement, GSK will also acquire a factory in Notre-Dame de Bondeville in France that employs about 650 people.
Meanwhile, Sanofi has revealed that the registration statement it had filed with the US Securities and Exchange Commission in connection with its proposed offer to Aventis has been declared effective and that it had commenced its US offer on 12 April.