Merck, Sanofi Pasteur Initiate Phase III Study of Vaccine to Help Prevent Six Infectious Diseases

Merck and Sanofi Pasteur announced today the initiation of a Phase III clinical program to evaluate the safety and immunogenicity of an investigational pediatric hexavalent combination vaccine1. This combination vaccine is designed to help protect against six potentially serious diseases: diphtheria, tetanus, whooping cough (Bordetella pertussis), polio (poliovirus types 1, 2, and 3), invasive disease caused by Haemophilus influenzae type b, and hepatitis B.

The investigational vaccine is a combination of select components: DTaP5-IPV-Hib-HepB; Diphtheria and Tetanus Toxoids and Acellular Pertussis Adsorbed, Inactivated Poliovirus, Haemophilus b Conjugate (Meningococcal Outer Membrane Protein Complex), and Hepatitis B (Recombinant) Vaccine. The vaccine is being developed as part of a partnership between Merck and Sanofi Pasteur that focuses on the development of pediatric combination vaccines.

"Combination vaccines simplify the childhood immunization schedule and may improve coverage, on time vaccination and reduce the number of injections for children," says Gary S. Marshall, MD, professor of pediatrics at the University of Louisville School of Medicine.

The Phase III clinical program will begin in the United States with a randomized, open-label, active-comparator controlled clinical trial that will involve approximately 1,440 infants at multiple centers. The primary study objectives are to assess the safety and immunogenicity of the investigational hexavalent combination vaccine when given at 2, 4, and 6 months of age concomitantly with Prevnar 13TM Pneumococcal 13-valent Conjugate Vaccine (Diphtheria CRM197 Protein) and ROTATEQ® (Rotavirus Vaccine, Live, Oral, Pentavalent). The clinical program is expected to begin in Europe this year. For more information on this study, please visit

The Phase III program was initiated following results from a Phase IIb clinical trial of 459 children that assessed the safety and immunogenicity of the investigational combination vaccine.

"Based on the results of Phase II trials, we are pleased to move this investigational hexavalent combination vaccine to a late-stage clinical program," says Michel DeWilde, PhD, senior vice president of research and development for Sanofi Pasteur. "We partnered with Merck to draw on the companies' combined leadership, experience and expertise in the development, manufacturing and marketing of pediatric combination vaccines."

In the United States, the Advisory Committee on Immunization Practices (ACIP), American Academy of Pediatrics (AAP), and American Academy of Family Physicians (AAFP) generally recommend the use of combination vaccines instead of individual injections, considering the potential for improved vaccination coverage.

"The need to consolidate vaccinations for infants will become increasingly important as the number of diseases that vaccines help prevent continues to increase," says Tony Ford-Hutchinson, PhD, senior vice president of vaccines research for Merck. "The development of a hexavalent combination vaccine is complex. The ability to share expertise and capabilities with our partner Sanofi Pasteur is fundamental in reaching our shared goal of developing new combination vaccines that may improve vaccination rates of children."