P0764Partial Responders to Intravenous Corticosteroids at Day 3 Benefit from Continued Therapy in Acute Severe Ulcerative Colitis

Background In acute severe ulcerative colitis (ASUC), early response patterns to intravenous corticosteroids (IVCS) during the first week may shape subsequent disease course. Characterizing these trajectories is crucial for guiding timely therapy and improving patient outcomes. Methods We evaluated response patterns to IVCS in hospitalized patients with ASUC. Clinical response was categorized as complete response (CR), partial response (PR), or non-response (NR) on days 3, 5, and 7. Patients were followed up to day 90 for disease activity, need for rescue therapy, and mortality. Results Seventy-nine patients were analyzed. By day 3, 12 (15%) achieved CR, 34 (43%) PR, and 33 (42%) NR. Among the 67 patients with PR or NR on day 3, 9 (13.4%) achieved CR by day 5 and 22 (32.8%) more by day 7. On day 7, CR, PR, and NR were observed in 42 (53%), 17 (21%), and 20 (25%) patients, respectively. Patients with CR on day 3 had a lower, but not statistically significant, likelihood of needing rescue therapy compared to NR (29% vs 47%; p = 0.15). However, by day 5, patients with CR or PR had significantly lower rescue therapy needs compared to NR (26% vs 54%, p = 0.02; 23% vs 54%, p = 0.03). By day 7, the probability of rescue therapy was higher in PR (45%) and NR (63%) versus CR (16%) (p = 0.001 and <0.0001, respectively). Conclusion Partial responders to IVCS at day 3 frequently achieve CR by day 5-7, highlighting the prognostic value of early response stratification. A PR or NR, beyond day 5, is associated with poorer outcomes. Conflict of interest: Dr. Singh, Arshdeep: No conflict of interest Bhardwaj, Arshia: No conflict of interest Sharma, Riya: No conflict of interest Singh, Dharmatma: No conflict of interest Jain, Devanshi: No conflict of interest Bansal, Namita: No conflict of interest Sebastian, Shaji: Grant: Takeda, Tillots pharma, Biogen, Pfizer, Abbvie, Johnson & Johnson, Olympus -Odin Vision Personal Fees: Tillots, Johnson & Johnson, Olympus Odin Vision, AbbVie, Takeda, Merck, Pharmacosmos, Amgen, Eli Lilly, BMS, Odin Vision Non-financial Support: Tillots, Takeda, AbbVie, Celltrion, Johnson & Johnson, Eli Lilly, Alphasigma, Ferring Pharma Peyrin-Biroulet, Laurent: CONSULTING Abbvie, Abivax, Adacyte, Alimentiv, Alfasigma, Amgen, Apini, Banook, BMS, Celltrion, Enthera, Ferring, Fresenius Kabi, Galapagos, Genentech, Gilead, Iterative Health, Janssen, Lilly, LifeMine, Medac, Morphic, MSD, Nordic Pharma, Novartis, Oncodesign Precision Medicine, ONO Pharma, OSE Immunotherapeuthics, Par’ Immune, Pfizer, Prometheus, Roche, Roivant, Samsung, Sandoz, Sanofi, Sorriso, Spyre, Takeda, Teva, ThirtyfiveBio, Tillots, Vectivbio, Vedanta, Ventyx. LECTURE Abbvie, Alfasigma, Amgen, Biogen, Celltrion, Ferring, Galapagos, Genentech, Gilead, Iterative Health, Janssen, Lilly, Medac, MSD, Nordic Pharma, Pfizer, Sandoz, Takeda, Tillots Midha, Vandana: No conflict of interest Sood, Ajit: Ajit Sood received honorarium for speaker events from Pfizer India and Takeda India.