This Combination Vaccine May Simplify Execution and Reduce Shots Needed to Complete CDC’s Recommended Child and Adolescent Immunization Schedule VAXELIS™ developed as part of a U.S.-based partnership between Merck known as MSD outside the United States and Canada, and Sanofi Pasteur, the global vaccines business unit of Sanofi, is now available in the U.S. VAXELIS is the first and only hexavalent combination ...