In advance of a prospective pivotal biosimilar safety and efficacy trial, researchers reviewing the data from the Phase III clinical trial of the reference molecule noted that approximately 20% of participants showed only a partial response to the molecule. With further analysis suggesting that these partial responders might constitute a clinically plausible and distinct subgroup, Michael F. Murphy, Aleksandra Bibic and Hazel Gorham at Worldwide Clinical Trials use this data to explore the potential for excluding subjects or otherwise adjusting and accounting for presumptively prognostically important variables