Downstream Change of the Primary Endpoint in the ISCHEMIA Trial: the Elephant in the Room

Modification of the Trial Protocol

Recently we learned that the protocol of the ISCHEMIA trial published on ClinicalTrials.gov had a major modification in January 2018, only 11 months before the estimated completion of this 7-year trial. The primary endpoint was changed from the composite of cardiovascular death or nonfatal MI (2012 version) to a 5-component endpoint that also includes resuscitated cardiac arrest, hospitalization for unstable angina and hospitalization for heart failure (January 2018 version).^,

Then, in February 2018, the full version of the 2012 ISCHEMIA protocol was published on ClinicalTrials.gov. This version of the protocol stated that if the incidence of the primary endpoint pooled across randomized groups is lower than expected, an independent advisory panel can decide to extend the follow-up period or change the primary endpoint.

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