FDA approves quadrivalent conjugate meningococcal vaccine

February 2005

The FDA granted approval recently to Sanofi Pasteur for its meningococcal conjugate vaccine (MCV4, Menactra) that provides protection against four serogroups of Neisseria meningitidis, A,C,Y and W-135.

MCV4 is designed to protect against meningococcal disease in those 11 to 55 years old and is the first quadrivalent conjugate vaccine licensed here.

Increased risk

“Adolescents and young adults are at increased risk for contracting meningococcal disease,” said Michael Pichichero, MD, professor of microbiology/immunology, pediatrics and medicine at the University of Rochester Medical Center, in a release. “The FDA licensure of [MCV4] vaccine, if it is coupled with widespread meningococcal immunization, represents a significant step toward eradicating this devastating disease.”

The company also plans to seek an indication for the use of the vaccine in children younger than 11.

Although meningococcal disease rates are highest in infants, rates begin to rise again in early adolescence and peak between the ages of 15 and 24. During the 1990s, one study reported substantially increased incidence among 15- to 24-year-olds. In addition, the fatality rate was over 22% in this age group, over five times that seen in younger people. Up to 83% of the cases reported in this study were caused by the serogroups that are covered by MCV4.

The FDA’s decision to approve MCV4 was based on safety and immunogenicity data from six studies, which included more than 7,500 adolescents and adults receiving the vaccine. The vaccine induced the production of functional antibodies specific to the capsular polysaccharides of the four serogroups found in the vaccine.

All vaccine immunogenicity measurements demonstrated strong immune responses to a single dose of MCV4 that were equivalent to a single dose of Sanofi Pasteur’s polysaccharide vaccine for protection against the same serogroups, combined (Menomune).

Additional findings demonstrated that in 98% to 100% of seronegative adolescents, the vaccine elicited fourfold increases in antibody titers to all four meningococcal serogroups. In adults, this range was 91% to 100%.

Recommendations

The Advisory Committee on Immunization Practices (ACIP) will likely make recommendations for use of the new vaccine at its meeting this month, based on a tentative list of recommendations members presented at the committee’s October meeting.

ACIP member Carol J. Baker, MD, professor of pediatrics, molecular virology and microbiology as well as head of the section of pediatric infectious diseases at Baylor College of Medicine in Houston, has said the vaccine would most likely be recommended for all college freshmen living in dormitories. She added it would be the preferred vaccine for high-risk people and travelers and for use during meningococcal outbreaks.

Neisseria meningitidis is the most frequent cause of bacterial meningitis in U.S. children and adolescents ages 2 to 18 years.

“In 2001, members of the CDC’s Active Bacterial Core Surveillance Team called upon the pharmaceutical industry to create a conjugate vaccine for protection against multiple serogroups of Neisseria meningitidis to combat the increased risk for disease in the adolescent population,” said Michael Decker, MD, MPH, vice president of scientific and medical affairs at Sanofi Pasteur, in the release. “We are pleased to respond to their challenge with the licensure of Menactra vaccine. All evidence indicates that widespread use of Menactra vaccine will help to reduce invasive meningococcal disease in the United States, thereby preventing many deaths and anguish for thousands of families.”