O63 Efficacy and Safety Outcomes Up to ~4 Years of Treatment with Filgotinib 200mg among SELECTIONLTE Patients with Ulcerative Colitis

Introduction Filgotinib (FIL) is an oral, JAK1 preferential inhibitor approved for the treatment of UC. FIL 200 mg (FIL200) was effective in inducing and maintaining clinical remission vs placebo (PBO) and well tolerated in the phase 2b/3 SELECTION trial (NCT02914522). The efficacy and safety of continued FIL200 are being assessed in the continuing SELECTION long-term extension (LTE; NCT02914535) study. Methods In SELECTION, adults with moderately to severely active UC received induction (IND) FIL200, FIL 100 mg (FIL100) or PBO once daily for 11 weeks. Patients in clinical remission or with a Mayo Clinic Score (MCS) response at week 10 (responders) could enter the 47-week Maintenance (MNT) Study. SELECTIONLTE enrolled patients who completed IND and MNT (completers), patients who were not responders at IND week 10 (non-responders), and patients with disease worsening during MNT. This interim analysis of the LTE population assessed the efficacy and safety of open-label FIL200 through LTE week 144 in completers and LTE week 192 in non-responders, respectively, representing a total of 3.9 years of treatment each. Continuous measures of partial MCS (pMCS) and proportions of patients achieving the MCID in total IBDQ score (≥16-point increase vs baseline) were assessed without imputation (as observed). Safety was assessed by the exposure-adjusted incidence rate per 100 patient-years of exposure (PYE) for treatment-emergent adverse events (TEAEs) and TEAEs of interest. Results This analysis included 148 completers and 372 non-responders (IND FIL100, n=212; IND FIL200, n=160). Among completers, the reductions in mean pMCS in SELECTION over weeks 0–10 were maintained up to LTE week 144 (figure 1). In non-responders, mean pMCS decreased from LTE baseline to week 192. High proportions of completers (>90%) and non-responders (>60%) achieved the MCID in IBDQ score; proportions were maintained over time. Safety events were as expected among all patients treated with open-label FIL200 in the LTE study (total PYE=2055.5). Conclusions FIL200 was effective in maintaining symptomatic remission and health-related quality of life for up to ~4 years. No new safety signals were observed over ~4 years of treatment, and safety events were comparable with those seen in previous analyses.