Introduction: Persistence on biologics in Crohn’s disease (CD) is an important measure, reflecting real-world treatment effectiveness, safety, and other factors. In the real world among bio-naïve patients with CD, evidence of superior one-year persistence on newer biologics, such as ustekinumab, relative to adalimumab exists, however, an understanding of persistence beyond one year is lacking.
Methods: Adults with CD initiated on ustekinumab or adalimumab between 09/23/2016 (approval of ustekinumab for CD in the US) and 08/01/2019 were selected from IBM® MarketScan® Commercial Database. Patients without other CD-indicated biologics (bio-naive) and diagnoses for other autoimmune diseases in the 12 months pre-index date (baseline) were included. No minimal follow-up was imposed post-index date. Persistence on index agent was defined as absence of gaps >120 days (ustekinumab) or >60 days (adalimumab) between days of therapy supply. Composite endpoints of being persistent and corticosteroid-free (no corticosteroids with ≥14 days of supply after day 90 post-index) and persistent while on monotherapy (no immunomodulators or non-index biologics) were also assessed. Cohorts were balanced on baseline characteristics using inverse probability of treatment weights. All endpoints were estimated at 24 months post-index using weighted Kaplan-Meier and Cox's proportional hazards models.
Results: There were 671 and 2,975 patients in the ustekinumab and adalimumab cohorts, respectively, and the cohorts were well-balanced at baseline (Table 1). At 24 months post-index, a significantly higher proportion of patients in the ustekinumab versus adalimumab cohort was persistent on index agent, as well as persistent and corticosteroid-free and persistent while on-monotherapy (Figure 1). At 24 months in ustekinumab versus adalimumab cohort, the rate of being persistent on index agent was 66% higher (hazard ratio [HR]: 1.66; 95% confidence interval [CI]: 1.40-1.97), the rate of being persistent and corticosteroid-free 15% higher (HR: 1.15; 95% CI: 1.01-1.31), and the rate of being persistent while on-monotherapy 44% higher (HR: 1.44; 95% CI: 1.26-1.64).
Discussion: Bio-naïve patients with CD initiated on ustekinumab versus adalimumab were significantly more persistent, more persistent and corticosteroid-free, and also more persistent while on-monotherapy 24 months after treatment initiation. These results are consistent with those in our previous work at 12 months.
