An editorial discusses why the primary outcome was not met and what can be learned from a study that failed its primary outcome. The author believes that despite missing its primary outcome, this trial is an important step forward in tailored management of patients with inflammatory bowel disease. He suggests it is likely that, with more research and increasing evidence, therapeutic drug monitoring will evolve into a 3-tiered approach: firstly, it will guide the induction regimen in some patients, then it will dictate proactive dose titrations over course of therapy to prevent disease flares and inflammatory activity; and if that fails or is unavailable, it will guide reactive interventions for patients with loss of response to anti-TNF agents. However, the commentator notes that many knowledge gaps still need to be researched and addressed to consolidate this 3-tier usage of pharmacokinetics.