Menactra is approved for those 11 to 55 years of age and is the first
quadrivalent conjugate licensed here.
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.
"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%.
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
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."