Abstract: Reporting of treatment-emergent adverse events (TEAEs) in rheumatoid arthritis (RA) clinical trials can be summarized as exposure-adjusted incidence rates (EAIRs) or exposure-adjusted event rates (EAERs). Censored EAIR (EAIR), weighing exposure up to a patient’s first event, is commonly reported; uncensored EAIR (EAIRu), using total exposure time for all patients, can also be used. For EAIR, exposure time can vary by event. In contrast to EAIR(u), the total number of events are used to calculate EAER. The three methods account for different exposures and/or multiple events, which can impact the outcome evaluation. Studies of filgotinib (FIL) in RA 1 report safety data as EAIR/100 patient-years of exposure (PYE) for TEAEs, which is uncensored. Objectives To describe the outcome of long-term FIL integrated safety data in RA by applying different statistical methodologies: EAER, EAIRu and EAIR. Methods Integrated FIL safety data from seven clinical trials were assessed 1 . Predefined adverse events of special interest (AESI) included serious infections (any), herpes zoster (HZ), major adverse cardiac events (MACE), malignancies (excluding nonmelanoma skin cancer [NMSC]), NMSC and venous thromboembolism (VTE). The number of patients with an event, number of events, EAER, EAIRu and EAIR were summarized. The data extraction date was January 2021 for the DARWIN 3 ( NCT02065700 ) long-term extension (LTE) and November 2020 for the FINCH 4 ( NCT03025308 ) LTE. Results In total, 3691 patients received ≥1 FIL dose for 8085 PYE. In this population, 176 serious infections were reported in 137 patients, 125 HZ events were reported in 112 patients, 39 MACE were reported in 33 patients, 20 cases of VTE were reported in 15 patients, 60 malignancies excluding NMSC were reported in 49 patients and 21 cases of NMSC were reported in 20 patients. Within each treatment arm (FIL 200 mg [FIL200], FIL 100 mg [FIL100] or combined FIL), rates for most AESI were similar when reported as EAER, EAIRu or EAIR (Table 1). For serious infections, EAER was higher than EAIRu or EAIR. The total exposure time to first event (censored PYE) was high and comparable to total exposure (PYE) ( 〉 2700 years and 〉 5100 years for the total populations in the FIL100 and FIL200 groups, respectively). Table 1. Exposure-adjusted event and incidence rates for AESI FIL200 FIL100 FIL combined Number of patients/PYE 2267/5302.5 1647/2782.6 3691/8085.1 Serious infections EAER 1.9 (1.5, 2.4) 3.2 (2.2, 4.5) 2.0 (1.7, 2.4) EAIRu 1.5 (1.1, 1.9) 2.7 (1.9, 3.9) 1.6 (1.3, 2.0) EAIR 1.5 (1.2, 1.9) 2.8 (1.9, 4.0) 1.7 (1.4, 2.0) HZ EAER 1.6 (1.3, 2.1) 1.3 (0.9, 1.8) 1.5 (1.2, 1.8) EAIRu 1.5 (1.2, 2.0) 1.1 (0.8, 1.5) 1.4 (1.1, 1.7) EAIR 1.6 (1.2, 2.0) 1.1 (0.8, 1.6) 1.4 (1.1, 1.7) MACE EAER 0.3 (0.2, 0.5) 0.6 (0.4, 1.0) 0.4 (0.3, 0.6) EAIRu 0.3 (0.2, 0.5) 0.5 (0.3, 0.8) 0.4 (0.2, 0.6) EAIR 0.3 (0.2, 0.5) 0.5 (0.3, 0.9) 0.4 (0.2, 0.6) VTE EAER 0.3 (0.2, 0.5) 0.1 (0.1, 0.4) 0.2 (0.2, 0.4) EAIRu 0.2 (0.1, 0.4) 0.1 (0.1, 0.4) 0.2 (0.1, 0.3) EAIR 0.2 (0.1, 0.4) 0.1 (0.1, 0.4) 0.2 (0.1, 0.3) Malignancies excluding NMSC EAER 0.8 (0.5, 1.1) 0.8 (0.5, 1.2) 0.7 (0.2, 2.8) EAIRu 0.6 (0.4, 0.9) 0.6 (0.4, 1.0) 0.6 (0.4, 0.8) EAIR 0.6 (0.4, 0.9) 0.6 (0.4, 1.0) 0.6 (0.4, 0.8) NMSC EAER 0.3 (0.2, 0.5) 0.2 (0.1, 0.5) 0.3 (0.2, 0.4) EAIRu 0.3 (0.2, 0.5) 0.2 (0.1, 0.4) 0.2 (0.2, 0.4) EAIR 0.3 (0.2, 0.5) 0.2 (0.1, 0.4) 0.2 (0.2, 0.4) Data are rate (95% CI) unless otherwise stated. Conclusion These data confirm that using different methods to analyze FIL safety data (EAER, EAIRu, EAIR) does not result in different safety outcomes, reinforcing the previously reported FIL safety profile in patients with RA. As the AESI reported in the long-term safety database with FIL are rare, patients commonly have long exposure times before experiencing an event, which are often associated with end of treatment. As such, EAIRu, EAIR and EAER are similar. References [1]Winthrop KL et al. Ann Rheum Dis 2021, doi: 10.1136/annrheumdis-2021-221051. Acknowledgements This study was co-funded by Galapagos NV (Mechelen, Belgium) and Gilead Sciences, Inc. (Foster City, CA, USA). Medical writing support was provided by Iain Haslam, PhD (Aspire Scientific Ltd, Bollington, UK), and funded by Galapagos NV. Disclosure of Interests Patrick Durez Speakers bureau: AbbVie, Galapagos, and Lilly, Eugen Feist Speakers bureau: AbbVie, Galapagos, Lilly, Novartis, Pfizer, Roche, and Sobi, Consultant of: AbbVie, Galapagos, Lilly, Novartis, Pfizer, Roche, and Sobi, Grant/research support from: Lilly, Pfizer, and Roche, Ricardo Blanco Speakers bureau: AbbVie, Amgen, Bristol-Myers, Galapagos, Janssen, Lilly, MSD, Novartis, Pfizer, Roche, and Sanofi, Consultant of: Astra-Zeneca, Galapagos, Janssen, Novartis, and Pfizer, Grant/research support from: AbbVie and Roche, Vijay Rajendran Employee of: Galapagos, Nadia Verbruggen Employee of: Galapagos, Katrien Van Beneden Shareholder of: Galapagos, Employee of: Galapagos, James Galloway Speakers bureau: AbbVie, Biogen, Galapagos, Gilead, Janssen, Lilly, Novartis, Pfizer, Roche, and UCB, Consultant of: AbbVie, Galapagos, Gilead, Janssen, Lilly, Novartis, and Pfizer, Grant/research support from: Astra-Zeneca, Celgene, Gilead, Janssen, Medicago, Novavax, and Pfizer

Abstract: The preferential Janus kinase-1 inhibitor FIL is approved for treatment of moderate to severe active RA in Europe and Japan. Objectives Efficacy and safety of FIL were assessed in patients (pts) with IR to bDMARDs in a LTE trial ( NCT03025308 ) enrolled from a Phase 3 PS ( NCT02873936 ). 1 Methods bDMARD-IR pts received FIL 200 mg (FIL200), FIL 100 mg (FIL100), or placebo (PBO), all with stable conventional synthetic (cs)DMARDs up to 24 weeks (W). At W14 of the PS, pts with IR to FIL or PBO ( 〈 20% improvement in swollen [66] and tender [68] joint counts) switched to standard of care (SOC; investigator’s choice of treatment). Pts completing the PS on FIL, PBO, or SOC could enter the LTE. PS FIL pts were maintained, blinded, on their FIL dose; PS PBO and PS SOC pts were rerandomized, blinded, to FIL200 or FIL100. Efficacy data to LTE W48 and safety data to data cutoff (June 1, 2020) are reported. Results The PS included 147, 153, and 148 pts on FIL200, FIL100, and PBO. Pts continuing on LTE FIL200 and FIL100 at data cutoff: 80/121 (66%) and 76/110 (69%) from PS FIL200 and FIL100; 35/47 (75%) and 32/46 (70%) from PS PBO, and 13/23 (57%) and 13/22 (59%) from PS SOC. LTE baseline (BL) characteristics were similar in FIL200 and FIL100 pts. During LTE, PS FIL ACR20/50/70 response rates decreased modestly by W48 (Figure 1). Among PS PBO pts, response rates were lower at LTE BL, reaching similar levels to PS FIL pts by W48; rates increased to W48 in PS SOC pts on either FIL dose but not to levels of other groups. Percentages of pts attaining DAS28(CRP) ≤3.2, DAS28(CRP) 〈 2.6, CDAI ≤10, and CDAI ≤2.8 were maintained up to W48 for FIL/FIL pts. PBO/FIL and SOC/FIL pts showed similar patterns to ACR responses (Figure 1). Exposure-adjusted incidence rates (EAIRs)/100 pt-years of exposure for treatment-emergent adverse events (TEAE), serious AEs, and serious infection were higher in SOC/FIL pts vs FIL/FIL or PBO/FIL pts, but samples were small and confidence intervals overlapped. There were 5 deaths (Table 1). Table 1. EAIRs of TEAEs in LTE, as of June 1, 2020 EAIR (95% CI) FIL200+csD → FIL200+csD n=121PYE 228.4 PBO+csD → FIL200+csD n=47PYE 98.1 SOC+csD → FIL200+csD n=23PYE 42.1 FIL100+csD → FIL100+csD n=110PYE 223.3 PBO+csD → FIL100+csD n=46PYE 91.1 SOC+csD → FIL100+csD n=22PYE 38.2 TEAE 46.9 (38.8, 56.6) 38.7 (28.2, 53.2) 52.2 (34.4, 79.3) 40.3 (32.8, 49.5) 40.6 (29.4, 56.1) 49.8 (31.8, 78.0) TEAE Grade ≥3 10.5 (7.0, 15.7) 10.2 (5.5, 18.9) 19.0 (9.5, 38.0) 10.3 (6.8, 15.5) 13.2 (7.5, 23.2) 18.3 (8.7, 38.5) TE serious AE 12.3 (8.5, 17.8) 12.2 (6.9, 21.5) 21.4 (11.1, 41.1) 8.1 (5.1, 12.8) 13.2 (7.5, 23.2) 21.0 (10.5, 41.9) Death 1.3 (0.4, 4.1) 1.0 (0, 5.7) 0 (0, 8.8) 0.4 (0.1, 3.2) 0 (0, 4.0) 0 (0, 9.7) TE infections 34.2 (27.4, 42.6) 22.4 (14.8, 34.1) 35.6 (21.5, 59.1) 22.4 (17.0, 29.5) 26.3 (17.7, 39.3) 39.3 (23.7, 65.2) TE serious infections 3.5 (1.8, 7.0) 2.0 (0.5, 8.2) 7.1 (2.3, 22.1) 0.9 (0.2, 3.6) 2.2 (0.5, 8.8) 7.9 (2.5, 24.4) Opportunistic infections 0 (0, 1.6) 0 (0, 3.8) 0 (0, 8.8) 0 (0, 1.7) 0 (0, 4.0) 0 (0, 9.7) TE herpes zoster 2.2 (0.7, 5.1) 1.0 (0.1, 7.2) 0 (0, 8.8) 0 (0, 1.7) 2.2 (0.5, 8.8) 2.6 (0.1, 14.6) TE MACE (adjudicated) 1.3 (0.4, 4.1) 1.0 (0.1, 7.2) 0 (0, 8.8) 0.9 (0.2, 3.6) 1.1 (0.2, 7.8) 0 (0, 9.7) TE DVT/PE (adjudicated) 0.9 (0.2, 3.5) 0 (0, 3.8) 2.4 (0.1, 13.2) 0.4 (0.1, 3.2) 0 (0, 4.0) 0 (0, 9.7) Malignancies (excluding NMSC) 1.3 (0.4, 4.1) 3.1 (1.0, 9.5) 4.7 (0.6, 17.2) 1.8 (0.7, 4.8) 3.3 (1.1, 10.2) 0 (0, 9.7) NMSC 0 (0, 1.6) 0 (0, 3.8) 4.7 (0.6, 17.2) 0 (0, 1.7) 0 (0, 4.0) 0 (0, 9.7) DVT, deep vein thrombosis; MACE, major adverse cardiovascular event; NMSC, nonmelanoma skin cancer; PE, pulmonary embolism; TE, treatment-emergent Conclusion Efficacy was mostly maintained in PS FIL pts up to W48. Response among PS PBO and SOC pts increased from BL to W48, but response in PS SOC pts continued to be lower than in other groups; these pts may represent a refractory population. FIL safety was largely consistent between PS and LTE. References [1]Genovese MC et al. JAMA 2019;322:315–25. Acknowledgements This study was funded by Gilead Sciences, Inc., Foster City, CA. Medical writing support was provided by Claudine Bitel, PhD, of AlphaScientia, LLC, San Francisco, CA; and funded by Gilead Sciences, Inc., Foster City, CA. Disclosure of Interests Maya H Buch Speakers bureau: AbbVie, Consultant of: AbbVie, Galapagos, Gilead, and Pfizer, Grant/research support from: Gilead and Pfizer, Tsutomu Takeuchi Speakers bureau: AbbVie, AYUMI, Bristol Myers Squibb, Chugai, Daiichi Sankyo, Dainippon Sumitomo, Eisai, Eli Lilly Japan, Gilead Sciences, Mitsubishi-Tanabe, Novartis, Pfizer Japan, and Sanofi, Consultant of: Astellas, Chugai, and Eli Lilly Japan, Grant/research support from: AbbVie, Asahi Kasei, Astellas, Chugai, Daiichi Sankyo, Eisai, Mitsubishi-Tanabe, Shionogi, Takeda, and UCB Japan, Vijay Rajendran Shareholder of: Galapagos, Employee of: Galapagos, Jacques-Eric Gottenberg Speakers bureau: AbbVie, Eli Lilly and Co., Galapagos, Gilead Sciences, Inc., Roche, Sanofi Genzyme, and UCB, Consultant of: Bristol Myers Squibb, Sanofi Genzyme, and UCB, Grant/research support from: Bristol Myers Squibb and Pfizer, Alena Pechonkina Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., YingMeei Tan Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Qi Gong Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Katrien Van Beneden Shareholder of: Galapagos, Employee of: Galapagos, Roberto Caporali Speakers bureau: AbbVie, Amgen, BMS, Celltrion, Galapagos, Janssen, Lilly, MSD, Novartis, Pfizer, Sandoz, and UCB, Consultant of: AbbVie, Amgen, BMS, Celltrion, Galapagos, Janssen, Lilly, Fresenius-Kabi, MSD, Novartis, Pfizer, Roche, Sandoz, and UCB

Abstract: Filgotinib (FIL) is a Janus kinase 1 preferential inhibitor approved for the treatment of moderate to severe rheumatoid arthritis (RA) in patients (pts) with an inadequate response to disease-modifying antirheumatic drugs. 1 In a pooled analysis of Phase 3 FINCH 1–3 studies of FIL in RA, median lymphocyte levels were relatively stable over 1 year with lymphocyte decreases observed in individual FIL-treated pts. Lymphocyte levels should be monitored. 1 Objectives To assess the effect of FIL on lymphocyte levels and lymphopenia in the FINCH 4 long-term extension (LTE) study in RA. Methods Safety data of FIL 100 mg (FIL100) and 200 mg (FIL200) from LTE baseline to data cut off (01 June 2020) are reported overall and by prior FIL exposure for pts who received ≥1 FIL dose in FINCH 4 ( NCT03025308 ; adults with RA who had completed FINCH 1/2/3). Adverse events (AEs) of lymphopenia were graded based on clinical severity; laboratory abnormalities (decreased lymphocytes) were graded per Common Terminology Criteria for Adverse Events v4.03 (CTCAE). Frequencies of both measures and exposure-adjusted incidence rates (EAIRs) of AEs are reported. Median lymphocyte levels are reported to LTE Week 48. Results The safety analysis set included 2729 pts (FIL200: n=1530; FIL100: n=1199). Of these, 75.4% (n=2058) had prior FIL exposure in FINCH 1/2/3. Median FIL exposure to LTE Week 48 was 600 (FIL200: 696; FIL100: 533) days. In both treatment groups, median laboratory lymphocyte levels remained relatively stable to LTE Week 48 for pts with prior FIL exposure. Pts without prior exposure had numerically higher median lymphocyte levels at LTE baseline vs pts with prior exposure (Figure 1). These decreased over time, but medians remained within normal range. The frequency and EAIR of graded decreases in laboratory lymphocyte levels were higher with FIL200 vs FIL100 (Table 1); incidence was slightly higher in pts with vs without prior FIL exposure, with the difference most apparent for Grade 2 decreases. Table 1. Frequencies of treatment-emergent laboratory decreases in lymphocytes Prior FIL exposure No prior FIL exposure Overall Total FIL200 FIL100 FIL200 FIL100 FIL200 FIL100 (N=2729) (n=1195) (n=863) (n=335) (n=336) (n=1530) (n=1199) Decreased lymphocytes 228 (19.1) 125 (14.5) 41 (12.3) 40 (12.0) 269 (17.6) 165 (13.8) 434 (16.0) (any grade), n (% ) Grade 1 48 (4.0) 35 (4.1) 14 (4.2) 7 (2.1) 62 (4.1) 42 (3.5) 104 (3.8) Grade 2 159 (13.3) 82 (9.5) 21 (6.3) 26 (7.8) 180 (11.8) 108 (9.1) 288 (10.6) Grade 3 21 (1.8) 8 (0.9) 6 (1.8) 7 (2.1) 27 (1.8) 15 (1.3) 42 (1.5) Grade 4 0 0 0 0 0 0 0 A treatment-emergent laboratory decrease in lymphocytes was defined as an increase of ≥1 toxicity grade from baseline at any time post-baseline up to and including the date of last study drug dose + 30 days. Severity grades were defined per CTCAE (lower limit of normal: 〈 0.8 × 10 9 /L [Grade 1]; 〈 0.8–0.5 × 10 9 /L [2]; 〈 0.5–0.2 × 10 9 /L [3]; 〈 0.2 × 10 9 /L [4]). Figure 1. Of all pts receiving FIL, 43 (1.6%) reported a lymphopenia AE; frequencies and EAIRs of lymphopenia AEs were slightly higher with FIL200 (1.9%; EAIR [95% CI]: 1.2 [0.9–1.8] ) vs FIL100 (1.2%; 0.8 [0.4–1.3]). Most were Grade 1 or 2 in severity. Grade 3 lymphopenia AEs occurred in 4 (0.3%) vs 1 ( 〈 0.1%) pts receiving FIL200 vs FIL100. There were no Grade 4 AEs in either group. No serious AEs of lymphopenia or treatment discontinuations due to lymphopenia were reported. In total, 8 (0.3%) pts interrupted study treatment due to lymphopenia. Infection rates, but not serious infections, were slightly higher for pts with lymphopenia, however no relationship between lymphopenia severity and infection AE grade was seen. Conclusion In FINCH 4, lymphopenia AEs were infrequent but numerically greater with FIL200 vs FIL100, suggesting a dose–response relationship. While exposure at either dose may be associated with decreased lymphocytes, median lymphocyte levels were comparable in both groups and all remained within normal range at LTE Week 48, similar to observations in FINCH 1–3. References [1]Filgotinib SmPC and Jyseleca EPAR, 2020. Available at: https://www.ema.europa.eu/en Acknowledgements The authors would like to acknowledge Nadia Verbruggen and Pieter-Jan Stiers for providing statistical analysis support. This study was co-funded by Galapagos NV (Mechelen, Belgium) and Gilead Sciences, Inc. (Foster City, CA, USA). Medical writing support was provided by Kristian Clausen, MPH, CMPP (Aspire Scientific Ltd, Bollington, UK), and funded by Galapagos NV. Disclosure of Interests Jacques-Eric Gottenberg Consultant of: AbbVie, Bristol Myers Squibb, Galapagos, Gilead, Lilly, and Pfizer, Grant/research support from: Bristol Myers Squibb, and Pfizer, Gerd Rüdiger Burmester Consultant of: AbbVie, Amgen, Bristol Myers Squibb, Galapagos, Lilly, MSD, Pfizer, Roche, and Sanofi, Katrien Van Beneden Shareholder of: Galapagos NV, Employee of: Galapagos NV, Chris Watson Shareholder of: Galapagos Biotech Ltd, Employee of: Galapagos Biotech Ltd, Ineke Seghers Employee of: Galapagos NV, Vijay Rajendran Employee of: Galapagos NV, Lorenzo Dagna Consultant of: AbbVie, Amgen, AstraZeneca, Biogen, Boehringer-Ingelheim, Bristol Myers Squibb, Celltrion, Eli Lilly and Company, Galapagos, GlaxoSmithKline, Janssen, Kiniksa Pharmaceuticals, Novartis, Pfizer, Roche, Sanofi-Genzyme, and Swedish Orphan Biovitrium (SOBI), Grant/research support from: Bristol Myers Squibb, Celltrion, Kiniksa Pharmaceuticals, Pfizer, and Swedish Orphan Biovitrium (SOBI), Maya H Buch Speakers bureau: Speaker fees paid to host institution by AbbVie, Consultant of: Consultant honoraria paid to host institution by AbbVie, Galapagos, Gilead, and Pfizer, Grant/research support from: Gilead and Pfizer.

Abstract: FIL is a Janus kinase (JAK) 1 preferential inhibitor approved for the treatment (tx) of moderate to severe RA. Weight gain has been reported with other JAK inhibitors 1–3 ; it is important to describe the effect of FIL on BW/BMI for physicians to correctly inform and appropriately treat patients. Objectives Our primary aim was to assess the effect of FIL on BW/BMI using data from the FINCH 1–3 studies. Secondary aims were to assess the efficacy and safety of FIL according to baseline BMI. Methods FINCH 1–3 ( NCT02889796 , NCT02873936 , NCT02886728 ) were phase 3, randomised, double-blind, active/placebo (PBO)-controlled studies of FIL 100/200 mg (FIL100/FIL200) ± methotrexate (MTX) in patients with active RA who had an inadequate response to MTX (FINCH 1) or biologic DMARD (FINCH 2), or were MTX naïve (FINCH 3). We assessed changes from baseline (CFB) in BW and BMI by tx group and baseline BMI, and the efficacy and safety of FIL by baseline BMI ( 〈 25, 25– 〈 30 or ≥30 kg/m 2 ). Efficacy measures included American College of Rheumatology (ACR)20/50/70 response, Disease Activity Score 28 with C-reactive protein (DAS28-CRP) and health assessment questionnaire disability index (HAQ-DI). Safety data were from 7 RA clinical trials (FINCH 1–4, DARWIN 1–3) 4 . Results In FINCH 1–3, baseline disease characteristics such as HAQ-DI, DAS28-CRP and clinical disease activity index were similar across BMI subgroups for each tx group. There were no clinically relevant CFB in median BW or BMI in any tx group or differences between tx groups. Mean CFB in BMI (kg/m 2 ) were 0.4 with FIL200 and FIL100 and 0.3 with adalimumab (ADA) at Week 52 in FINCH 1; 0.2, 0.6 and −0.1 with FIL200, FIL100 and PBO, respectively, at Week 24 in FINCH 2; and 0.5, 0.6, 1.1 and 0.3 with FIL200+MTX, FIL100+MTX, FIL200 and MTX, respectively, at Week 52 in FINCH 3. CFB in BMI did not appear dependent on baseline BMI. FIL200±MTX was efficacious vs controls regardless of baseline BMI for most measures at each timepoint. In FINCH 1, in the 〈 25, 25– 〈 30 and ≥30 kg/m 2 BMI subgroups, DAS28-CRP 〈 2.6 was achieved by 38%, 29% and 33% of the FIL200 group, 29%, 19% and 21% of the ADA group, and 7%, 10% and 11% of the PBO group at Week 12, respectively. Figure 1 shows ACR20 responders by baseline BMI in FINCH 1–3. Integrated safety data across baseline BMI subgroups are summarised in Table 1. VTE rate was numerically higher with FIL200 in the ≥30 than 25– 〈 30 or 〈 25 kg/m 2 BMI subgroups; serious infection rate was numerically higher with FIL100 in the 〈 25 mg/m 2 subgroup vs other BMI subgroups. Table 1. Exposure-adjusted incidence rate (95% CI) of AEs per 100 PYE by baseline BMI FIL dose (mg) BMI (kg/m 2 ) 〈 25 25– 〈 30 ≥30 PYE 3062.8 PYE 2640.1 PYE 2382.2 TEAEs 200 34.5 (32.0, 37.1) 35.7 (33.0, 38.6) 36.6 (33.7, 39.8) 100 44.3 (40.4, 48.6) 43.0 (38.9, 47.5) 45.3 (41.1, 50.0) Serious TEAEs 200 5.3 (4.4, 6.4) 5.8 (4.8, 7.1) 7.1 (5.8, 8.5) 100 7.6 (6.0, 9.4) 6.5 (5.0, 8.4) 8.1 (6.4, 10.2) Deaths 200 0.3 (0.2, 0.7) 0.5 (0.3, 1.0) 0.5 (0.2, 1.0) 100 0.4 (0.1, 1.0) 0.3 (0.1, 1.0) 0.2 (0.1, 0.9) Venous thrombotic and embolic events 200 0.1 (0.0, 0.4) 0.1 (0.0, 0.5) 0.5 (0.2, 1.0) 100 0.1 (0.0, 0.7) 0.1 (0.0, 0.8) 0.2 (0.1, 0.9) Major adverse cardiovascular events 200 0.3 (0.2, 0.7) 0.3 (0.1, 0.7) 0.5 (0.2, 1.0) 100 0.6 (0.3, 1.3) 0.3 (0.1, 1.0) 0.6 (0.2, 1.4) Serious infections 200 1.1 (0.7, 1.7) 1.7 (1.2, 2.5) 1.8 (1.2, 2.6) 100 2.6 (1.8, 3.9) 1.2 (0.7, 2.2) 2.2 (1.4, 3.4) Herpes zoster 200 1.6 (1.1, 2.2) 1.4 (1.0, 2.1) 1.8 (1.2, 2.6) 100 1.0 (0.5, 1.8) 1.2 (0.7, 2.2) 1.0 (0.5, 2.0) Malignancy excluding nonmelanoma skin cancer 200 0.5 (0.3, 1.0) 0.7 (0.4, 1.3) 0.5 (0.3, 1.1) 100 0.6 (0.3, 1.3) 0.4 (0.2, 1.2) 0.8 (0.4, 1.7) BMI, body mass index; FIL, filgotinib; PYE, patient years of exposure; (TE)AE, (treatment-emergent) adverse event Conclusion FIL did not substantially affect CFB in BW or BMI. FIL200±MTX was generally more efficacious vs controls regardless of baseline BMI, and the rate of TEAEs was similar across baseline BMI subgroups. References [1]Tofacitinib SmPC [2]Baracitinib SmPC [3]Upadacitinib SmPC [4]Winthrop K, et al. ACR 2021. Abstract 1698 Acknowledgements The FINCH studies were funded by Gilead Sciences (Foster City, CA, United States). We thank the physicians and patients who participated in the studies. Medical writing support was provided by Debbie Sherwood, BSc (Aspire Scientific Ltd, Bollington, UK) and funded by Galapagos NV (Mechelen, Belgium). Disclosure of Interests Alejandro Balsa Speakers bureau: AbbVie, Galapagos, Gilead, Lilly, Nordic, Pfizer, Sandoz, and UCB, Consultant of: AbbVie, Galapagos, Lilly, Nordic, Pfizer, and UCB, Grant/research support from: AbbVie, Pfizer, UCB, Siegfried Wassenberg Speakers bureau: AbbVie, MSD, Pfizer, and Sanofi, Consultant of: AbbVie, Gilead, Lilly, Nichi-Iko, Pfizer, and UCB, Grant/research support from: Pfizer, Anne Tournadre Speakers bureau: Fresenius-Kabi and Sanofi, Paid instructor for: Fresenius-Kabi, Consultant of: AbbVie, Fresenius-Kabi, Lilly, Novartis, and Sanofi, Grant/research support from: Novartis, Pfizer, and UCB, Hans-Dieter Orzechowski Employee of: Galapagos, Katrien Van Beneden Shareholder of: Galapagos, Employee of: Galapagos, Vijay Rajendran Employee of: Galapagos, Udo Lendl Employee of: Galapagos, Pieter-Jan Stiers Shareholder of: Galapagos, Employee of: Galapagos, Chris Watson Shareholder of: Galapagos, Employee of: Galapagos, Roberto Caporali Speakers bureau: AbbVie, Accord, BMS, Celltrion, Fresenius-Kabi, Galapagos, Lilly, MSD, Novartis, Pfizer, Sandoz, and UCB, Consultant of: AbbVie, Accord, BMS, Celltrion, Fresenius-Kabi, Galapagos, Lilly, MSD, Novartis, Pfizer, Sandoz, and UCB, Patrick Verschueren Speakers bureau: Eli Lilly, Galapagos, MSD, and Roularta, Consultant of: AbbVie, BMS, Celltrion, Eli Lilly, Galapagos, Gilead, Nordic Pharma, Pfizer, Sidekick Health, and UCB, Grant/research support from: Pfizer Chair Management of Early Rheumatoid Arthritis at KU Leuven Belgium.