Retrospective Observational Study Shows Combination Vaccines May Improve Vaccination Coverage Rates In Infants

Main Category: Immune System / Vaccines
Also Included In: Pediatrics / Children's Health;  Clinical Trials / Drug Trials
Article Date: 28 May 2007 - 0:00 PST

email to a friend   printer friendly   view / write opinions

A new analysis from a retrospective observational study of administrative claims data from the Georgia State Medicaid program showed that infants who received at least one shot of PEDIARIX ® [Diphtheria and Tetanus Toxoids and Acellular Pertussis Adsorbed, Hepatitis B (Recombinant) and Inactivated Poliovirus Vaccine Combined] or Comvax® [Haemophilus b Conjugate (Meningococcal Protein Conjugate) and Hepatitis B (Recombinant) Vaccine] had higher immunization coverage rates for most of the vaccines or vaccine series studied in the first two years of life compared to infants given no doses of either of these combination vaccines. Results from the study were published in the June 2007 issue of the Pediatric Infectious Disease Journal.

"The routine immunization schedule for children has grown more complex as new vaccines have been added," said Dr. Gary Marshall, Professor of Pediatrics, Division of Pediatric Infectious Diseases, University of Louisville School of Medicine, Louisville, KY. "While this is good news in the sense that it means more protection against disease, it also means more difficulty delivering the shots. Results from this study suggest that by using combination vaccines and thereby decreasing the number of shots while providing the same protection, we can facilitate completion of the recommended series."

The retrospective analysis of records from 18,821 infants enrolled in the Georgia Medicaid program showed that children who had received one or more doses of the combination vaccines PEDIARIX or Comvax had significantly higher coverage rates for several recommended vaccines or vaccine series than those who had received no doses of either of these combination vaccines, including:

Four doses of diphtheria, tetanus and acellular pertussis (DTaP) vaccine (77.6 percent verses 72.7 percent; p<0.0001)

Three doses of polio vaccine (85.4 percent verses 79.6 percent; p<0.0001)

The 4:3:1 vaccine series (four doses of DTaP, three doses of IPV and one dose of MMR) (71.7 percent verses 65.9 percent; p<0.0001)

The 4:3:1:3:1 vaccine series (four doses of DTaP, three doses of IPV, one dose of MMR, three doses of Hib, and one dose of varicella) (67.2 percent verses 62.3 percent; p<0.0001)

The 3:3:3 vaccine series (three doses of DTaP, three doses of IPV and three doses of Hib) (78.9 percent verses 73.8 percent; p<0.0001)1G

Children who received one or more doses of PEDIARIX or Comvax did not have higher coverage rates for the following vaccines:

One dose of measles, mumps and rubella (MMR) (94.3 verses 94.8; p=.2684)

Three or four doses of Hib (87.6 verses 86.7; p=.1647)

One dose of varicella (94.4 verses 94.1; p=.5058)

About the Study

The observational study, which was funded by GlaxoSmithKline, evaluated the immunization history of infants born between January and September 2003, with continuous enrollment in the Georgia Medicaid Program for at least 24 months following birth, identified from administrative claims of the Georgia Department of Community Health. Infants who were eligible for the study were divided into two groups. The combination group (N=16,007) was made up of those infants who received at least one dose of PEDIARIX or Comvax. The reference group (N=2,814) consisted of those infants who did not receive any doses of either PEDIARIX or Comvax. Children in either cohort may have received doses of TriHIBit® [diphtheria-tetanus-whole-cell pertussis (DTP) and Haemophilis influenzae type b (Hib)]. Forty-four percent of the combination group received at least one dose of PEDIARIX and 68 percent received at least one dose of Comvax. Infants with fewer than four vaccination visits were excluded from the analysis. Immunization coverage rates were evaluated at 24 months of age by calculating the percentage of children who received the recommended number of doses of each vaccine according to the immunization schedule recommended by the Centers for Disease Control and Prevention's (CDC) Advisory Committee on Immunization Practices (ACIP), the American Academy of Pediatrics (AAP), and the American Academy of Family Physicians (AAFP).

About PEDIARIX

PEDIARIX is indicated for active immunization against diphtheria, tetanus, pertussis (whooping cough), all known subtypes of hepatitis B virus, and polio caused by poliovirus Types 1, 2, and 3 as a three-dose primary series in infants born to mothers who do not have hepatitis B, beginning as early as 6 weeks of age. PEDIARIX has been studied in numerous clinical trials, where 23,849 doses of PEDIARIX were administered to 8,088 infants. PEDIARIX should not be administered to any infant before the age of 6 weeks, or to individuals 7 years of age or older. PEDIARIX has been marketed in the United States since 2003.

In clinical studies, adverse events in infants receiving PEDIARIX included injection-site reactions (pain, redness, or swelling), fever and fussiness. Administration of PEDIARIX was associated with higher rates of fever relative to separately administered vaccines (see Adverse Reactions section of the package insert). PEDIARIX is contraindicated in infants with known hypersensitivity to any component of the vaccine including yeast, neomycin, and polymyxin B. As with any vaccine, vaccination with PEDIARIX may not protect 100 percent of susceptible individuals.

PEDIARIX is manufactured by GlaxoSmithKline Biologicals, Rixensart, Belgium and distributed by GlaxoSmithKline.

GlaxoSmithKline: A Leader in Vaccines

GlaxoSmithKline, with U.S. operations in Philadelphia, PA, and Research Triangle Park, NC, is one of the world's leading research-based pharmaceutical and healthcare companies and is committed to improving the quality of human life by enabling people to do more, feel better and live longer. For company information, visit GlaxoSmithKline at http://www.gsk.com.

GSK Biologicals (GSK Bio), one of the world's leading vaccine manufacturers, is headquartered in Rixensart, Belgium, where the majority of GlaxoSmithKline's activities in the field of vaccine research, development and production are conducted. GSK Bio employs more than 1,500 scientists, who are devoted to discovering new vaccines and developing more cost-effective and convenient combination products to prevent infections that cause serious medical problems worldwide. In 2006, GSK Bio distributed more than 1.1 billion doses of vaccines to 169 countries in both the developed and the developing world an average of 3 million doses a day. Of those vaccine doses, approximately 136 million were doses of combination pediatric vaccines which protect the world's children from up to six diseases in one vaccine.

Comvax ® is a registered trademark of Merck & Co., LLC.

TriHIBit® is a registered trademark of Sanofi Pasteur