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MADISON, NJ. -- February 5, 2001 -- Wyeth Lederle Vaccines, a business unit of Wyeth-Ayerst Laboratories, the pharmaceutical division of American Home Products Corporation, announced that Prevenar® (pneumococcal saccharide conjugated vaccine, adsorbed) received marketing authorization from the European Commission representing 15 European countries.

Prevenar is the first and only pneumococcal conjugate vaccine indicated for infants and young children up to two years old to help prevent invasive pneumococcal disease caused by the seven serotypes (4, 6B, 9V, 14, 18C, 19F and 23F) of Streptococcus pneumoniae (S. pneumoniae) contained in the vaccine. Each year more than one million children throughout the world die as a result of pneumococcal disease. In industrialized nations, the annual incidence of invasive pneumococcal disease, including meningitis and bacteremia, in children less than two years old is estimated to be as high as 160 cases per 100,000.

"The approval of Prevenar marks a significant advance in pediatric medicine, as the first effective vaccine for the prevention of serious pneumococcal disease in infants and young children," said Kevin Reilly, President, Wyeth Lederle Vaccines. "As pneumococcal disease continues to be a growing threat to children worldwide, Prevenar helps offer needed protection from this potentially devastating illness."

Prevenar helps provide protection against invasive disease caused by seven capsular serogroups of S. pneumoniae, specifically 4, 6, 9, 14, 18, 19 and 23. The vaccine covers 71 to 86 percent of the serogroups known to cause invasive pneumococcal illnesses in European children less than two years of age. The frequency of pneumococcal serotypes and serogroups can vary from country to country and could influence the effectiveness of the vaccine in any given country.

Prevenar also has the potential to protect children against antibiotic-resistant S. pneumoniae serogroups, as the seven serogroups in Prevenar represent about 80 percent of antibiotic-resistant bacterial isolates in Europe.

Pneumococcal disease describes a group of illnesses caused by the bacterium S. pneumoniae, which includes invasive pneumococcal diseases such as bacteremia (bacterial infection of the blood), sepsis (blood poisoning), meningitis (bacterial infection of the membrane of the spinal cord or brain) and pneumonia associated with bloodstream infections. If not treated or resistant to treatment, these illnesses can result in paralysis, brain damage and even death. S. pneumoniae also causes non-invasive infections such as bacterial pneumonia, sinusitis (infection of the sinuses), and acute otitis media (middle-ear infections), which may lead to hearing loss, learning disabilities and speech delays.

Because 90 different serotypes of S. pneumoniae exist, development of an effective pneumococcal vaccine has been challenging. Moreover, the rapid emergence of antibiotic-resistant S. pneumoniae serogroups remains a significant problem in most countries and can make the management of pneumococcal disease more difficult.

Until recently, the only vaccine available against invasive pneumococcal disease was a 23-valent pneumococcal polysaccharide vaccine, which is unable to stimulate an adequate immune response in infants and young children younger than two years. In contrast, each capsular saccharide in Prevenar is individually conjugated, or attached, to a protein carrier, CRM197 (cross-reactive material). As a result, Prevenar effectively stimulates the immune systems of infants and also creates immune system memory.

The efficacy and safety profile of Prevenar were demonstrated through several clinical trials, including a clinical study of more than 37,000 infants, which found that Prevenar was 97.4 percent effective in preventing serotype-specific invasive pneumococcal infections in infants who were fully vaccinated, and 89.1 percent effective for all cases of invasive pneumococcal disease regardless of serogroup.

In the United States, Prevenar (marketed as Prevnar®) was approved in February 2000 and made available the same month. More than 10 million doses of the vaccine have already been distributed in the United States alone. Prior to EC authorization, Prevenar was cleared for marketing in the United States, Switzerland, Argentina, Australia, Peru, Mexico, Curacao, Trinidad/Tobago and Malta.

The labeling for Prevenar also references important data on the prevention of acute otitis media caused by the seven serotypes of S. pneumoniae contained in Prevenar. In a European study of approximately 1,600 infants, Prevenar was found to be 57 percent effective in preventing serotype-specific cases of acute otitis media (AOM) and 34 percent effective against all cases of culture-confirmed pneumococcal AOM. A separate study found that Prevenar reduced the need for surgical ear tube insertion by approximately 20 percent. While Prevenar is expected to significantly reduce the incidence of AOM in children, a significant burden of otitis media will remain after Prevenar is introduced, primarily because other bacteria and viruses also cause the condition.

In clinical studies conducted in the United States, France, Germany, the United Kingdom and Finland, Prevenar was found to be well tolerated in more than 20,000 children with more than 60,000 doses administered. Most reactions to the vaccine, such as local irritations and fever, were mild, resolved spontaneously and were comparable to those commonly observed with other vaccines. The most frequently reported adverse events in infants included injection site reactions, fever (less than 38 C), irritability, drowsiness, restless sleep, decreased appetite, vomiting, diarrhea and rash or hives.