Differences in the need for adalimumab dose optimization between Crohn's disease and ulcerative colitis

to compare the need for and time to adalimumab dose escalation and de-escalation between patients with Crohn's disease (CD) and ulcerative colitis (UC).

this observational cohort study included patients with luminal CD or patients with UC treated with adalimumab. Adalimumab dose optimization was decided based on the Harvey-Bradshaw index (CD) or the partial Mayo score (UC). The co-primary endpoints were the differences in the rate of dose escalation and the cumulative probability of escalation-free survival between cohorts. We also evaluated the rates of de-escalation and predictors of adalimumab dose escalation and de-escalation.

twenty-four of 43 CD patients (56%) and 28 of 43 UC patients (65%) required adalimumab dose escalation. UC patients had a higher adjusted rate of dose escalation (hazard ratio [HR] 2.33, 95% confidence interval [CI] 1.19-4.56; p = 0.013) than CD patients. The median time to dose escalation was significantly shorter for UC than CD patients (3.2 months, interquartile range [IQR]: 2.0-10.3 vs 12.2 months, IQR: 6.1-35.7; p = 0.001). Survival curves showed that UC patients had an increased probability of dose escalation (p < 0.001). Prior anti-TNF therapy was associated with dose escalation (HR 2.13, 95% CI 1.05-4.34; p = 0.037). Adalimumab dose de-escalation was attempted in 32% of UC patients and 50% of CD patients. Survival curves showed that CD patients had an increased probability of dose de-escalation (p = 0.030).

UC patients more frequently required adalimumab dose escalation than CD patients. UC patients required optimization earlier than CD patients. More CD patients than UC patients can be dose de-escalated later on during treatment.