Net Remission Rates with Biologic Treatment in Crohn's Disease: A Reappraisal of the Clinical Trial Data.

Biologic therapies have greatly advanced the medical care of patients with Crohn's disease (CD); however, up to 50% of patients have no response and up to 80% fail to achieve remission. One way to investigate this treatment gap in CD is to look at the "net" remission rates in clinical trials defined as the actual percentage of patients enrolled during induction who are in remission at the end of maintenance. Indeed, most of the seminal clinical trials in CD used a "responder" methodology, where only patients who responded during induction were rerandomized to maintenance.