Prophylactic Efficacy of Relenza Against Influenza A and B
Status:
Completed
Trial end date:
2010-05-01
Target enrollment:
Participant gender:
Summary
In response to the European regulatory authorities, GSK is conducting a post-marketing
observational study to assess the efficacy of Relenza when used as prophylaxis against
influenza.
SPECIFIC AIMS
1. Determine the frequency of patients who received Relenza from October 2006 through April
2009, and among them the number who have no concurrent diagnosis of influenza, i.e.,
those receiving Relenza for prophylaxis, and among these the number who have a family
member with a medical visit for influenza within three days preceding the above
indentified patient's dispensing of Relenza. This is to determine the feasibility of
conducting detailed analysis.
2. If analysis is feasible then tabulate the frequency of influenza-like-illness and
respiratory outcomes in users of prophylactic Relenza and their family members and in
family members of persons using Relenza for the treatment of influenza (i.e., index
cases).
3. If analysis is feasible then estimate the direct effect of prophylactic Relenza on the
occurrence of influenza-like-illness and respiratory outcomes, the secondary effect of
Relenza treatment of influenza on susceptible family members, and the total effect of
Relenza (treatment plus prophylaxis).
METHODS Overview of Study Design This is an analysis of the 30-day risk of influenza-like
illness and respiratory outcomes in persons for whom some household members (index cases)
have had a medical visit associated with a diagnosis of influenza. The exposed individuals to
the index case will be categorized into one of four cohorts according to whether the exposed
person received prophylactic Relenza or no antiviral treatment and by whether the index
family member with a diagnosis of influenza received antiviral treatment.
Estimates of the direct effect of Relenza prophylaxis, the indirect effectof preventing
disease in susceptible family members, and the total effect of disease reduction when both
index cases and susceptible family members are treated will be obtained from different
comparisons between cohorts, as outlined below.
The research will cover the first three influenza seasons during which Relenza has been
indicated for prophylactic use in the United States. These will be from October through April
of 2006-2009.