On June 30, Sanofi declined 3.15% overnight, trading at $42.06/share, with turnover of $1,687.

The decline follows the European Commission's announcement on June 26 of a formal antitrust investigation into Sanofi over a suspected breach of EU competition rules. The regulator is concerned that Sanofi carried out a communication campaign disparaging CSL Seqirus' flu vaccine Fluad to promote its own Efluelda vaccine among healthcare professionals in Germany and France. The Commission noted that Sanofi's claims — suggesting Fluad's evidentiary basis is weaker than Efluelda's — contradict findings by the European Centre for Disease Prevention and Control and national immunization advisory groups in both countries. If found in violation, Sanofi could face fines of up to 10% of global annual revenue.

The probe compounds existing pressures on Sanofi, which replaced its CEO in February amid pipeline setbacks and recently halted a late-stage autoimmune disease trial. The new CEO faces the dual challenge of rebuilding the R&D pipeline ahead of Dupixent's patent expiration while navigating heightened regulatory scrutiny.

(The above content is based on publicly available market information, generated by a program or algorithm, and is intended solely as a stock movement alert. It does not constitute investment advice or a basis for trading decisions.)