Is that Adverse Experience Really Expected? Guidelines for Interpreting and Formatting Adverse Experience Information in the United States

What is an “expected” or “labeled” adverse reaction versus an “unexpected” or “unlabeled” adverse event or experience? Unfortunately, present guidelines that assist with this assessment are not well defined, thus creating ambiguity in their interpretation and application. In an attempt to establish a definitive framework for assessing “expectedness” or “labeledness,” formalized guidelines for interpreting and formatting safety information have been drafted. Although this article is written from a United States regulatory perspective, many of the guidelines can be applied globally.