P0852UPARECOL-UC: Real-world effectiveness and safety of upadacitinib in ulcerative colitis in a Colombian cohort

Abstract Background Ulcerative colitis (UC) requires effective therapeutic strategies to induce and maintain remission. Upadacitinib, a selective JAK1 inhibitor, has shown strong efficacy in clinical trials; however, real-world evidence in Latin American populations remains scarce. The UPARECOL-UC study evaluated the effectiveness and safety of upadacitinib in Colombian patients with UC during induction (8–16 weeks) and maintenance (24 weeks) under routine clinical practice. Methods A prospective multicentre cohort study was conducted across Colombian reference centres including adults with confirmed UC (clinical, endoscopic, and histological criteria) who initiated upadacitinib between 2024 and 2025 for ≥8 weeks. Effectiveness outcomes included clinical response, clinical remission, and steroid-free remission. Objective biomarkers (C-reactive protein, faecal calprotectin, haemoglobin) were monitored at baseline and follow-up. Safety variables included adverse events (AEs), serious AEs, infections, and treatment discontinuation. Results A total of 47 patients were included in the induction analysis. After 8–16 weeks, clinical remission was achieved in 61.7% (29/47), with steroid-free remission in 71.4% of responders. At week 24, clinical remission increased to 90% (18/20), and steroid-free remission reached 88.2%. Endoscopic remission (Mayo 0–1) was 85% among patients reassessed endoscopically during maintenance. Significant reductions in inflammatory biomarkers were observed during follow-up, supporting clinical improvement. Colectomy occurred in 5.4% of patients during induction, with no colectomies during maintenance. Overall, 30.2% experienced any AE; acne was the most common (25.6%). Serious infections occurred in 4.7% . Treatment discontinuation due to AEs occurred in 9.3% of the cohort. No new safety signals were identified. Conclusion Upadacitinib demonstrated high real-world effectiveness for both induction and maintenance in this Colombian UC cohort, composed largely of patients with severe and treatment-refractory disease. Improvements in clinical outcomes were accompanied by significant reductions in inflammatory biomarkers. The safety profile was consistent with previous clinical and real-world data, supporting upadacitinib as an effective therapeutic option for UC in routine practice. Conflict of interest: Parra Izquierdo, Leidy Viviana: No conflict of interest Gil Parada, Fabio Leonel: No conflict of interest Juliao Baños, Fabián: No conflict of interest Puentes-Manosalva, Fabian Eduardo: No conflict of interest Cuervo-Pico, Pedro-Eduardo: No conflict of interest Galiano, Maria Teresa: No conflict of interest Riveros, Javier: No conflict of interest Gomez Venegas, Alvaro: No conflict of interest Medrano-Almanza, Carlos Andres: No conflict of interest Perea, Daniel: No conflict of interest Ballesteros, Manuel: No conflict of interest Barreto Perez, Jonathan: No conflict of interest Cuadros-Mendoza, Carlos Augusto: No conflict of interest Guzman, Gerardo: No conflict of interest Gutierrez Raba, Aura: No conflict of interest Soto Mora, Jahir: No conflict of interest Dr. Frías-Ordoñez, Juan: No conflict of interest