The French Competition Authority is investigating whether Sanofi-Aventis has acted in an unfair way to prevent generic versions of its blockbuster bloodthinner Plavix gaining market share.

The FCA has agreed to a request brought by the French subsidiary of Israel’s Teva Pharmaceutical Industries to investigate alleged anti-competitive practices by Sanofi. In November last year, Teva filed a complaint saying that these practices had the effect of excluding generic drugs competing with Plavix (clopidogrel).

According to the FCA, Sanofi's communications toward scientists and practitioners “emphasise differences between Plavix and competing generics”. However it is alleged that this has been done “without
revealing that these differences have no impact on the therapeutic efficacy of the product, and that the generic formulation has been fully tested and approved for use by medical authorities across Europe”.

Gerard van Odijk, chief executive of Teva Europe, welcomed the ruling, saying that the authority's decision to investigate Sanofi’s behaviour “underlines our view that such practices are likely to prevent access to competition and damage the long-term interests of patients”. The FCA rejected a request from Teva to immediately sanction Sanofi but will launch a probe to see if the latter’s practices constitute legitimate commercial defence or could be interpreted as abusive. The investigation is expected to take several months.

Generic Plavix is already making in-roads into Sanofi’s earnings. The drug, which is partnered with Bristol-Myers Squibb, brought in 535 million euros to the Paris-headquartered firm’s coffers in the first quarter, down 21.3%, and in Europe sales fell 43.5% due to the introduction of competition.