The European Commission has opened an antitrust investigation into French pharmaceutical company Sanofi over allegations that it violated European Union competition rules while promoting its influenza vaccine, according to AFP.

The investigation focuses on Efluelda, Sanofi's enhanced influenza vaccine designed for adults aged 60 and older. The vaccine competes directly with Fluad, a rival product developed by Australian pharmaceutical company CSL Seqirus.

According to the European Commission, it is concerned that Sanofi may have conducted a misleading marketing campaign aimed at discrediting Fluad by portraying it as less effective than Efluelda. Regulators argue that these claims may have conflicted with national vaccination recommendations in several EU member states.

The Commission said the campaign primarily targeted healthcare professionals in Germany and France, where Sanofi holds a strong market position in influenza vaccines.

Sanofi previously disclosed that it was under investigation and maintains that it has complied fully with all applicable laws.

"The company is confident that it has acted, and continues to act, in full compliance with all applicable laws and regulations, including competition rules," Sanofi said in a statement.

The company also described the investigation as a procedural step that does not predetermine the outcome of the case. Sanofi reaffirmed its commitment to fair competition and ensuring patient access to innovative vaccines.

Influenza vaccines represent an important part of Sanofi's business and are widely used in national immunization programs, particularly in France.

If the European Commission concludes that Sanofi abused a dominant market position or breached EU competition rules, the company could face substantial financial penalties and may be required to implement corrective measures.