How Blind Should the Investigators and Sponsors Be?

• Activity Number: 235
• Type: Topic Contributed
• Date/Time: Monday, August 5, 2013 : 2:00 PM to 3:50 PM
• Sponsor: Biometrics Section
• Author(s): James Neaton*+
• Companies: University of Minnesota
• Keywords: DSMB ; clinical trial ; interim monitoring

Abstract

It is generally accepted that Data and Safety Monitoring Boards (DSMBs) should be the only group with access to interim safety and efficacy summary data comparing treatments in a clinical trial. However, there are circumstances in which aggregate outcome data may be needed by investigators or sponsors conducting the trial. For example, pooled outcome data may be needed for sample size re-estimation and for determining the closing date of an event drive trial. In addition, if the aim of the trial is to determine the effect of an intervention which modifies a risk factor or blood marker on clinical outcomes, investigators may want access to interim summaries of changes in the risk factor in order to assess whether trial goals are being met and adherence to the intervention. In some cases, it may even be necessary to share interim treatment comparisons due to concerns about safety or to counteract the findings of another trial. Case examples are used to illustrate situations where interim information might be considered and how it might be done.