Feagan, B.

Abstract Background Tumor necrosis factor-like ligand 1A (TL1A) is upregulated in inflammatory bowel disease and believed to promote inflammation and intestinal fibrosis. RO7790121, an anti-TL1A antibody, showed promising results in the phase IIa TUSCANY trial.1 Here we report post-hoc analyses of patient-reported outcomes from the TUSCANY-2 trial. Methods This phase IIb, multicenter, randomized, double-blind, treat-through, dose-ranging study evaluated RO7790121 in patients (pts) aged 18–75 years with moderately to severely active ulcerative colitis (UC) (total Mayo score [MS] ≥6, endoscopic subscore ≥2). Pts were randomized to receive subcutaneous (SC) RO7790121 50mg, 150mg, 450mg or matched placebo (PBO) monthly during the 12-week induction period, and SC RO7790121 50mg, 150mg or 450mg monthly during the 40-week treat-through maintenance period. To assess efficacy of RO7790121 in supporting pts achieving early symptomatic improvement, rectal bleeding (RB), stool frequency (SF) and partial modified MS (RB+SF) were evaluated at baseline and Weeks 2, 4, 8, 12 and 14. The exploratory endpoint of symptomatic remission, defined as a RB subscore of 0 and a SF subscore of 0 or 1, was assessed throughout induction. Safety was assessed throughout the study. Results Overall, 245 pts received ≥1 dose of RO7790121 or PBO. At Week 2, pts receiving RO7790121 were more likely to report a RB subscore of 0 (34% RO7790121; 20% PBO) and less likely to report a RB subscore of 2 or 3 (25% RO7790121; 40% PBO) (Figure). Improvements in SF increased from Week 2 and throughout induction, with ~60% of pts receiving RO7790121 reporting a SF subscore of 0 or 1 at Weeks 12 and 14, vs ~40% for PBO. Greater rates of symptomatic remission were observed in pts receiving RO7790121 vs PBO throughout induction and from Week 2 (17.5% RO7790121; 8.9% PBO) (Table). Treatment-emergent adverse events (TEAEs) were reported during induction in 117/245 pts, the most common (reported in ≥5% of pts in any treatment group) were nausea, urinary tract infection and UC (highest in the 50mg arm), anemia (highest in the placebo arm) and fatigue, headache and pyrexia (highest in the 450mg arm). Serious TEAEs were reported in ten pts during induction (PBO=4; 50mg=3; 450mg=3); two were treatment related (PBO=1; 450mg=1). There were six treatment discontinuations due to TEAEs and a generally similar safety profile was observed during the maintenance period. Conclusion Greater and earlier improvements in RB and SF were observed in pts receiving RO7790121 vs PBO. These results indicate early symptom relief and a favorable safety profile for pts treated with RO7790121, supporting its further clinical development. RO7790121 is currently being evaluated in phase III studies (NCT06589986 and NCT06588855). References 1.Danese S, Klopocka M, Scherl EJ, et al. Anti-TL1A antibody PF-06480605 safety and efficacy for ulcerative colitis: A phase 2a single-arm study. Clin GastroenterolHepatol. 2021;19(11):2324-2332.e6. http://doi.org/10.1016/j.cgh.2021.06.011