Vaccine Combinations Appear Safe, Effective

PHILADELPHIA — Administering two or more vaccines simultaneously was safe and immunogenic in results from two separate studies reported at the annual meeting of the Infectious Diseases Society of America.

The results from combined administration of the human papillomavirus (HPV) vaccine; a vaccine for tetanus, diphtheria, and pertussis (Tdap); and a quadrivalent, conjugated meningococcal formulation (MCV4) are especially relevant to practice because all three are already approved for U.S. use, and the concept of delivering all three simultaneously received endorsement by the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices in 2007 (MMWR 2007;56:1-24).

The only piece missing until now was data showing that the concomitant strategy was safe and immunogenic—something the new study now provides, said Cosette M. Wheeler, Ph.D., professor of pathology and obstetrics and gynecology at the University of New Mexico in Albuquerque.

Her study used Cervarix (HPV vaccine), Boostrix (Tdap), and Menactra (meningococcal vaccine). Cervarix and Boostrix are marketed by GlaxoSmithKline, which funded the study. Menactra is marketed by Sanofi Pasteur. in addition to receiving research support from GlaxoSmithKline, Dr. Wheeler also received funding for studies from Merck, which markets the HPV vaccine Gardasil, and from Roche Molecular Systems.

The study enrolled 1,283 healthy girls aged 11-18 years at 48 U.S. centers. The researchers randomized the participants to one of six different treatment schemes: HPV vaccine only at months 0, 1, and 6; HPV with Tdap at month 0 followed by HPV only at months 1 and 6; HPV with the meningococcal vaccine at month 0 followed by HPV only at months 1 and 6; all three vaccines at month 0 followed by HPV only at months 1 and 6; Tdap only at month 0 followed by HPV only at months 1, 2, and 7; and MCV4 only at month 0 and then HPV only at months 1, 2, and 7.

The results showed that 1 month after the subjects received any of the concomitant doses, their immune responses all fell within the prespecified criteria for noninferiority, compared with the responses when the vaccines were administered individually.

The second study examined concomitant administration of an investigational, 13-valent, conjugated pneumococcal vaccine and the trivalent, seasonal influenza vaccine of 2007-2008 in 1,106 healthy adults aged 50-59 years, said Dr. Robert W. Frenck Jr., professor of pediatrics at Cincinnati Children's Hospital Medical Center.

The pneumococcal vaccine was developed by Wyeth (which recently was acquired by Pfizer Inc.), which funded the study. Dr. Frenck had no other conflicts to disclose for his study.

He and his associates randomized subjects to receive either the pneumococcal and flu vaccines together at month 0 followed by placebo at month 1, or the flu vaccine and placebo at month 0 followed by the pneumococcal vaccine at month 1.

One month after vaccination, the immune responses to both vaccines in people who received them simultaneously fell within the prespecified noninferiority limit, compared with the responses in people who received the two vaccines 1 month apart, Dr. Frenck reported. Simultaneous administration also resulted in similar rates of local and systemic reactions compared with giving the vaccines 1 month apart.

Immune response in people who received vaccines simultaneously fell within the noninferiority limit.

Source DR. FRENCK