P192 Efficacy of filgotinib in rheumatoid arthritis by age, body weight, body mass index: post hoc subgroup analysis of two phase 3 trials
Authors: Tanaka Yoshiya , Curtis Jeffrey , Wassenberg Siegfried , Kiely Patrick , Ye Lei , Yin Zhaoyu , Downie Bryan , Enomoto Hiroyuki , Strengholt Sander , Akhdar Ali , Watson Chris , Atsumi Tatsuya 
Published: April 2022

Abstract

Background/Aims
Filgotinib (FIL), an oral Janus kinase 1 preferential inhibitor, has demonstrated safety and efficacy as treatment for signs and symptoms of RA, and it is approved in Japan and Europe for treatment of RA. Patient characteristics can influence response to RA treatment; this post hoc analysis was performed to determine whether age, body weight (BW), and body mass index (BMI) influenced efficacy.

Methods
Patients from FINCH 1 (F1, n = 1755, inadequate response to methotrexate [MTX-IR]; NCT02889796) or FINCH 3 (F3, n = 1249, MTX-naïve; NCT02886728) were included for analysis of clinical response at week 12 (F1 primary endpoint) or 24 (F3 primary endpoint). Patients were stratified by age (&lt;65, ≥65 years), BW (&lt;60, 60 to &lt; 100, ≥100 kg), and BMI (&lt;25, ≥25 kg/m2). Efficacy was assessed by ACR20, Disease Activity Score-28 &lt;2.6, Clinical Disease Activity Index ≤2.8, Simple Disease Activity Index ≤3.3, Boolean remission, and change from baseline in Health Assessment Questionnaire-Disability Index (HAQ-DI). Selected efficacy endpoints are displayed in Table 1. Patients treated with FIL200+MTX were compared with control arms (F1, placebo+MTX; F3, MTX). Fisher’s exact test was used for binary endpoints; mixed-effects model for repeated measures was used for HAQ-DI. P-values were nominal without adjusting for multiplicity.

Results
FIL200+MTX in MTX-IR patients demonstrated greater efficacy vs placebo+MTX regardless of age, BW, and BMI (Table 1). Apart from the ≥65-year-old subgroup, in which there was no clear pattern, FIL200+MTX in MTX-naïve patients demonstrated greater efficacy vs MTX across subgroups (Table 1). Rates of treatment-emergent adverse events (TEAEs) were greater in the ≥65-year-old subgroup vs the &lt;65-year-old subgroup; there was no discernible pattern between BMI subgroups. Among MTX-naïve patients only, rates of TEAEs were higher in those who weighed ≥100 kg vs lower-weight subgroups.

Conclusion
This exploratory analysis showed FIL200+MTX was efficacious regardless of subgroup characteristics defined by age, BW, or BMI. Most comparisons of FIL200+MTX vs MTX and vs placebo+MTX favored FIL200+MTX.

Disclosure
Y. Tanaka: Consultancies; Eli Lilly, Daiichi-Sankyo, Taisho, Ayumi, Sanofi, GSK, and AbbVie. Member of speakers’ bureau; Daiichi-Sankyo; Eli Lilly; Novartis; YL Biologics; Bristol-Myers; Eisai; Chugai; AbbVie; Astellas; Pfizer; Sanofi; Asahi-Kasei; GSK; Mitsubishi-Tanabe; Gilead Sciences, Inc.; and Janssen. Grants/research support; AbbVie, Mitsubishi-Tanabe, Chugai, Asahi-Kasei, Eisai, Takeda, and Daiichi-Sankyo. J. Curtis: Grants/research support; from AbbVie, Amgen, BMS, Corrona, Eli Lilly, Janssen, Myriad, Pfizer, Regeneron, Roche, and UCB. S. Wassenberg: Consultancies; AbbVie; Amgen; BMS; Gilead Sciences, Inc.; Eli Lilly; Hexal; MSD; Nichi-Iko; Pfizer; and Sanofi. P. Kiely: Member of speakers’ bureau; Novartis, Lilly, Galapagos, Sobi, Abbvie. L. Ye: Shareholder/stock ownership; Employee and shareholder of Gilead Sciences, Inc. Z. Yin: Shareholder/stock ownership; Employee and shareholder of Gilead Sciences, Inc. B. Downie: Shareholder/stock ownership; Employee and shareholder of Gilead Sciences, Inc. H. Enomoto: Shareholder/stock ownership; former employee/shareholder of Gilead Sciences, Inc. S. Strengholt: Shareholder/stock ownership; shareholder of and employee of Galapagos BV. A. Akhdar: Shareholder/stock ownership; shareholder of and employee of Galapagos BV. C. Watson: Shareholder/stock ownership; shareholder of and employee of Galapagos BV. T. Atsumi: Honoraria; Gilead Sciences, Inc.; Mitsubishi Tanabe; Chugai; Astellas Pharma; Takeda; Pfizer; AbbVie: Eisai; Daiichi Sankyo Co. Ltd.; BMS; UCB Japan Co. Ltd.; Eli Lilly, Otsuka Pharmaceutical Co. Alexion Inc.