Comparative Effectiveness of Low Versus High Dose Upadacitinib as Maintenance Treatment in Patients with Ulcerative Colitis: A Real-World Cohort Study From the United States

Background There is limited real-word data comparing efficacy of low dose upadacitinib (UPA) to high dose UPA as maintenance therapy for ulcerative colitis (UC). Methods This was a retrospective cohort study utilizing the U.S. Collaborative Network in adults ≥ 18 years old with UC who initiated UPA 15 mg compared to 30 mg for maintenance therapy between April 2022-December 2023. The primary outcome was a composite of intravenous steroid use, oral steroid use or colectomy from 12 to 60 weeks from the index UPA prescription. Propensity score matching (PSM) was performed for demographics, co-morbid conditions, laboratory and IBD medication history. Cox proportional hazard model was used to identify predictors of failure. Results Among 1,110 patients on UPA maintenance therapy, 361 (32.5%) were on 15 mg and 749 (67.5%) were on 30 mg. After PSM, there was no difference in the composite outcome of steroid use or colectomy between the 15 mg UPA cohort vs 30 mg cohort (35.3% vs 35.6%; aHR 0.95, 0.71-1.24, p = 0.8). There was no difference in IV steroid use, oral steroid use or change in therapy between the two cohorts. There was no difference in the proportion of patients who achieved a fecal calprotectin of < 250 ug/g (55.8% vs 63.5%, p = 0.33). Recent oral or IV steroid use and rheumatoid arthritis were associated with failure of both 15 mg and 30 mg UPA. Conclusion Our study indicates that 15 mg UPA shows similar efficacy as 30 mg UPA for maintenance treatment in a subset of patients with UC.