Dressing Preparations for Smallpox
Condition: Smallpox
MeSH terms: Smallpox
Study type: Interventional
Phase: Phase 1/Phase 2

Summary: 
      The primary purpose of this study is to find out the risk of spreading the vaccine virus,
      vaccinia, from the smallpox vaccination site when different types of bandages are used to
      cover the site. The study will also look at how each bandage type affects the healing of the
      sore. Study participants will include healthy individuals, 18-50 years old, who have not
      previously received a smallpox vaccine and healthy individuals, 18-50 years old, who have
      received a previous smallpox vaccine. All participants will receive the smallpox vaccine and
      be randomly assigned to 1 of 3 different bandage groups to cover the vaccine site: standard
      gauze dressing attached with paper tape, Opsite gauze-impregnanted occlusive dressing
      (attached by paper tape and waterproof), and Allevyn hydropolymer dressing (which is
      self-adhesive and highly absorbent). Volunteers will be involved in study related procedures
      for up to 252 days.
    

Detailed description: 
      This study will investigate the potential for secondary transmission of vaccinia from
      smallpox vaccination sites covered by various types of dressings, as well as the effects of
      each dressing type on the healing of the vaccination lesion. The results could have great
      implications for infection control and public health in the wake of potential mass smallpox
      vaccination. The study population will consist of two cohorts: healthy individuals who are
      naive to the smallpox vaccine ("naive group") and healthy individuals who have had previous
      vaccination with the smallpox vaccine ("experienced group"). Individuals in each group will
      be vaccinated with a dose of smallpox vaccine diluted to 1:5 and will be randomized to
      receive one of three dressing preparations to cover the vaccination site: standard 2 inch x 2
      inch gauze attached to the skin via paper tape ("Gauze dressing"); Opsite gauze-impregnated
      occlusive dressing ("occlusive dressing"); and Allevyn hydropolymer dressing (Smith and
      Nephew, "hydropolymer dressing"). In addition, 30 of the 108 subjects (15 naïve and 15
      experienced) will be enrolled as a "cardiac subgroup" and will have additional blood drawn
      for the assessment of specific biochemical markers related to thrombosis and platelet
      activation (specifically, plasminogen-activator inhibitor type 1 (PAI-1) and soluble CD40
      ligand (sCD40L). The primary study objective will be the assessment of infectivity of
      vaccination sites via evaluation of vaccinia growth from specimens of the outer dressing for
      each bandage type. Positive culture reflects failure of the bandage to prevent possible
      spread of vaccinia. Secondary study objectives include the following: assessment of
      infectivity of vaccination sites via evaluation of vaccinia growth from specimens from the
      hand contralateral to the vaccine site for each dressing type; comparison of the rate of
      lesion healing (time from vaccination until lesion is deemed "well-healed") for each dressing
      cohort; association of adverse events (AEs) involved with transmission of vaccinia, such as
      autoinoculation and secondary dissemination, with the type of dressing covering the
      vaccination site; and determination of the alterations after smallpox vaccination in the
      body's endogenous fibrinolytic system to investigate the potential pathophysiology of adverse
      ischemic cardiac events seen in vaccinated subjects in the recent civilian and military
      campaigns. The tertiary objectives of the study include: assessment of the overall safety
      profile in each cohort, as determined by reactogenicity of the vaccine and the development of
      expected and unexpected AEs unrelated to dressing type; assessment of the efficacy of a 1:5
      dilution of APSV in vaccinia-experienced adults as measured by the proportion of individuals
      who respond to vaccination with a "take: 6-11 days after vaccination; characterization of the
      humoral immune response generated following vaccination in each cohort; assessment of
      pharyngeal carriage and shedding of vaccinia virus in each cohort of vaccinated volunteers;
      and assessment of the tolerability of the dressing and total number of bandage changes
      determined from a volunteer questionnaire and summarized by bandage type. Volunteers will be
      followed for 56 days following their primary vaccination. Volunteers who do not have a "take"
      will be offered revaccination under a separate protocol after their 56-day blood sample is
      drawn. All volunteers will be contacted by telephone for information about serious adverse
      events at or about 180 days after their primary vaccination.
    

Intervention name(s): Wetvax (APSV)
Intervention type(s): Biological
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: Smallpox, wetvax