PneuMum: Pneumococcal Vaccination of Australian Indigenous Mothers
Condition: Middle Ear Effusion; Tympanic Membrane Perforation; Acute Otitis Media; Pneumococcal Infections
MeSH terms: Pneumococcal Infections; Otitis Media; Tympanic Membrane Perforation; Otitis Media with Effusion
Study type: Interventional
Phase: Phase 3

Summary: 
      PneuMum is a randomised controlled trial that aims to find out if pneumococcal vaccination
      for Australian Indigenous mothers, in the last few months of pregnancy or at delivery, can
      prevent ear disease in infants. Mothers will receive the 23 valent pneumococcal
      polysaccharide vaccine (23vPPV) either: a) during the third trimester of pregnancy; b) soon
      after child birth; or c) seven months after child birth (control group). The adult
      diphtheria, tetanus and acellular pertussis vaccine (dTpa) will be used as the control
      vaccine for the birth dose.

      The study aims to recruit 210 Indigenous women aged 17-39 years who have an uncomplicated
      pregnancy. Following recruitment, subjects will be randomly assigned to one of the three
      groups.

      Each mother and infant will be followed from pregnancy until the baby is seven months of age.
      All routinely recommended vaccinations on the standard vaccination schedule will continue to
      be offered by the subject's vaccine provider in accordance with current clinical practice.

      The primary outcome will be prevalence of middle ear disease at seven months of age, defined
      as middle ear effusion or tympanic membrane perforation or acute otitis media. Pneumatic
      otoscopy, video-otoscopy and tympanometry will be used in the ear examinations. The primary
      analyses will be a direct comparison of the proportion of infants in the control group who
      have nasopharyngeal carriage of one or more vaccine type pneumococci at seven months of age
      compared to infants in each of the other two groups. A similar comparison of the proportion
      with middle ear disease will be undertaken between the control group and the respective
      intervention group.
    

Detailed description: 
      PneuMum is a randomised controlled trial that aims to find out if pneumococcal vaccination
      for Australian Indigenous mothers, in the last few months of pregnancy or at delivery, can
      prevent ear disease in infants. Two vaccines will be used in this trial:

        -  The 23 valent pneumococcal polysaccharide vaccine (23vPPV), is currently recommended for
           all Indigenous people in the Northern Territory from 15 years of age but uptake among
           women of child-bearing age has been low.

        -  Adult diphtheria, tetanus and acellular pertussis vaccine (dTPa) will be used as the
           control vaccine. This vaccine is recommended for all new parents who have not previously
           been immunised but is not currently funded so would normally need to be purchased on
           prescription through a pharmacist.

      Rationale

      Indigenous children experience the highest rates of acute and chronic ear infections in the
      world, resulting in permanent ear damage, hearing loss and educational disadvantage. These
      infections are mainly bacterial. Streptococcus pneumoniae (pneumococcus) is the predominant
      pathogen. Pneumococcal colonisation and infection begins within days of birth, months before
      any potential immunological protection from infant pneumococcal conjugate vaccine may be
      expected. New strategies are needed to eliminate, or at least delay, this early-onset
      pneumococcal colonisation.

      Maternal vaccination with the 23 valent pneumococcal polysaccharide vaccine (23vPPV) during
      pregnancy or at delivery is one strategy that may protect newborn infants through mechanisms
      such as transplacental antibody transfer, increased secretory antibody in breast milk, and/or
      by reducing nasopharyngeal carriage (and transmission to the infant) of maternal pneumococci.
      Previous small studies using this strategy have been encouraging, but there have been no
      studies properly evaluating nasopharyngeal carriage or disease endpoints in infants.

      Methods

      We aim to recruit 210 Indigenous women aged 17-39 years who have an uncomplicated pregnancy.
      Following recruitment, subjects will be randomly assigned to one of three groups:

        -  Group A will receive 23vPPV in the last few months of pregnancy

        -  Group B will receive 23vPPV soon after childbirth

        -  Group C will receive 23vPPV seven months after childbirth (the control group).

      Women in Groups A and C will receive dTpa soon after childbirth (to conceal the intervention
      groups), whereas women in Group C will be offered dTpa seven months after childbirth (end of
      the observation period).

      Study participants will be visited at least five times:

        1. During the last few months of pregnancy (30-36 weeks gestation)

           - The group of mothers receiving 23vPPV at this visit will also have a pre-vaccination
           blood sample collected

        2. At Royal Darwin Hospital when the baby is born

             -  Each mother will receive either 23vPPV or dTpa depending on their allocation

             -  Each mother will have a pre-vaccination blood sample, cord blood sample, a
                nasopharyngeal swab and a sample of expressed breast milk taken

        3. When the baby is one month old

           - Each baby will have their ears checked utilising pneumatic otoscopy, video-otoscopy
           and tympanometry. A nasopharyngeal swab will be taken. A swab will also be taken of any
           discharge from the baby's ear/s. Mothers will be asked for sample of expressed breast
           milk and a post vaccine maternal blood sample will be collected.

        4. When the baby is two months old

           - The same checks and samples as the previous month with the exception of maternal blood
           sample unless this has not previously been collected.

        5. When the baby is seven months old - Each mother and baby will have the same checks and
           samples as per the two month visit. Babies will also have a sample taken of their blood.
           Mothers who have not yet had 23vPPV will be offered that vaccine as will those who have
           not yet had dTpa.

      Primary Outcome

      The primary outcomes will be:1)prevalence of middle ear disease at seven months of age; and
      2)prevalence of nasopharyngeal carriage of vaccine type (23vPPV) pneumococci. The primary
      analyses will be a direct comparison of the proportion of infants in the control group (Group
      C) who have nasopharyngeal carriage of vaccine type pneumococci at seven months of age
      compared to infants in each of the other two groups and a similar comparison of the
      proportion with middle ear disease.
    

Intervention name(s): 23vPPV, dTpa (Pneumovax, Boostrix); 23vPPV, dTpa (Pneumovax, Boostrix); 23vPPV, dTpa (Pneumovax, Boostrix)
Intervention type(s): Biological; Biological; Biological
Intervention description(s): Group A will receive 23vPPV during 3rd trimester and dTpa at delivery; Group B will receive 23vPPV at delivery and dTpa 7 months following delivery; Group C will receive dTpa at delivery and 23vPPV 7 months following delivery
Other intervention name(s): Pneumovax, Boostrix; Pneumovax, Boostrix; Pneumovax, Boostrix
Intervention MeSH terms: Edetic Acid; Heptavalent Pneumococcal Conjugate Vaccine; Pentetic Acid
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Prevention