The European Commission opened an investigation on Friday into whether French drugmaker Sanofi breached EU competition rules in a flu vaccine marketing campaign. The Commission said it was concerned that Sanofi had carried out a misleading campaign to sell its "Efluelda" flu vaccine while disparaging a rival one called "Fluad" made by CSL Seqirus, primarily in France and Germany. In both markets, Sanofi holds a dominant position, the Commission added. "Sanofi is confident that it has acted, and