Response to Expression of Concern Regarding VIGOR Study

Abstract
We, the non-Merck authors of the VIGOR study,1 welcome the opportunity to respond to your recent expression of concern2 regarding the VIGOR study. No Merck employee or representative was involved in the drafting of this response. Our evaluation leads us to conclude that our original article followed appropriate clinical trial principles and does not require a correction. Three basic assertions were made in the expression of concern, and we would like to address these assertions point by point.