A randomized trial of an investigational 9-valent pneumococcal conjugate vaccine (PCV-9) or placebo given to pregnant women during the last trimester to prevent early infant otitis media (OM) was conducted. All infants received Prevnar® at 2, 4, 6, and 12 months. Clinic and adverse event records were reviewed to identify OM. Variables significantly related to acute OM by age 6 months (p<0.05) were: vaccine group (9 valent or placebo), sibling history of tympanostomy tubes, upper respiratory infection, and number of clinic visits by 6 months. Infant OM rates were similar between 6 and 12 months (58% and 56%). Results suggested that immunizing pregnant women with PCV-9 increased infants' risk of acute OM in the first 6 months of life, and this correlated with decreased infant antibody responses to their infant Streptococcus pneumoniae vaccine serotypes, but did not influence antibody responses to 3 other serotypes two of which were in maternal vaccine (types 1 and 5) and one was a control (type 7F). Explanations for these results include dampening of infant antibody production by high levels of passively acquired maternal pneumococcal antibodies and/or altered B lymphocyte immune responses in infants exposed to these specific polysaccharide antigens in utero.
Bibliographical noteFunding Information:
Grant support was provided by the National Institute of Deafness and Communication Disorders : P50 DC03093 , P50 DC03093-05S1 , and R01 DC005974 . The National Institute of Allergy and Infectious Diseases was the Investigational New Drug (IND) holder. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute on Deafness and Other Communication Disorders or the National Institutes of Health. Wyeth Lederle Vaccine and Pediatrics provided the 9-valent pneumococcal conjugate vaccine and placebo for maternal use, and the 7-valent pneumococcal conjugate vaccine (Prevnar ® ) for study infants. We would like to thank the mothers and their infants whose dedication made this study possible, research nurses Elaine Stier, Debi Frerichs and Mary Meester of the HealthPartners Research Foundation (HPRF), coordinators Julie Toth and Pam Kaufman, HealthPartners physician advisors Joan Madden, Mary Meland, Lawrence Condon and nurse practitioner Georgeanne Croft, HealthPartners physicians and nurse practitioners who performed infant examinations, HPRF medical record abstractor Linda Loes, Data Safety and Monitoring Board members Drs. Kathryn Edwards, Maurizio Maccato, Shrikant Bangdiwala, Kenneth Trofatter, Eugene Shapiro, and Timothy Landers, NIAID/DMID sponsor Dr. George Curlin, NIDCD sponsor Dr. Julianna Gulya, and regulatory affairs specialists Wendy Fanaroff-Ravick and Janie Russel (NIAID). This trial would not have been possible without the expertise and contributions of all these individuals and entities.
© 2014 Elsevier Ltd.
- Maternal immunization
- Otitis media
- Pneumococcal antibodies