Efficacy Trial of Two Pneumococcal Conjugate Vaccines (PncCRM and PncOMPC) for Prevention of Acute Otitis Media Due to Vaccine Serotypes

This was a randomized, double-blinded multicenter cohort study of Finnish children aged 2 to 24 months. The study was designed to evaluate the efficacy of two 7-valent pneumococcal conjugate vaccines (PncCRM and PncOMPC) parallelly, both vaccines compared with the same control vaccine (hepatitis B vaccine). The primary endpoint was culture-confirmed pneumococcal acute otitis media (AOM) episodes due to all serotypes included in the pneumococcal conjugate vaccine and the primary hypothesis was that, compared to the control vaccine group, the pneumococcal conjugate vaccine would protect infants from culture confirmed AOM caused by pneumococcal serotypes in the vaccine. The efficacy of the two vaccines against any pneumococcal AOM and any AOM was also evaluated. The children were vaccinated with the pneumococcal conjugate vaccine or the control vaccine at the age of 2, 4, 6 and 12 months and followed at study clinics established specifically for the purpose from 2 to 24 months of age. Whenever AOM was diagnosed during the follow-up, middle ear fluid was aspirated for bacterial culture.