Sanofi 

Sanofi develops and markets drugs with a concentration in immunology, vaccines, and rare diseases. Although the company offers a diverse array of drugs, its highest-revenue product, Dupixent, accounts for over 30% of total sales. Profits for this immunology blockbuster drug are shared with Regeneron. About 45% of total revenue comes from the United States, 20% from Europe, and 6% from China.