Gilead and Galapagos Announce 52-Week Data from Two Phase 3 Trials of Filgotinib in Rheumatoid Arthritis

Compiled by S.Li

Recently, Gilead Sciences and Galapagos jointly announced the Week 52 data from two Phase 3 clinical trials, FINCH 1 and FINCH 3, evaluating filgotinib for the treatment of moderately to severely active rheumatoid arthritis (RA). The results demonstrated that after 52 weeks of treatment, filgotinib exhibited sustained efficacy and a consistent safety profile in patients with RA.

The FINCH 1 study evaluated the efficacy and safety of filgotinib in patients with moderately to severely active rheumatoid arthritis (RA) who had an inadequate response to methotrexate (MTX-IR), compared with placebo or adalimumab, against a background of stable MTX dosing. Patients were randomized to receive once-daily filgotinib 200 mg (n=475), once-daily filgotinib 100 mg (n=480), adalimumab 40 mg every other week (n=325), or corresponding placebo (n=475). The primary endpoint was the proportion of patients achieving an ACR20 response at Week 12 compared with placebo.

As previously reported, the filgotinib 200 mg group met the primary endpoint. Filgotinib demonstrated superiority over placebo across all secondary endpoints related to signs and symptoms of rheumatoid arthritis (RA), physical function, and structural damage.

Furthermore, at Week 52, a greater proportion of patients in the 200 mg treatment group achieved low disease activity (DAS28[CRP] ≤ 3.2) and clinical remission (DAS28[CRP] < 2.6) compared with the adalimumab group. Based on CDAI ≤ 2.8 and Boolean remission criteria, patients in the 200 mg treatment group demonstrated a greater reduction from baseline in the Health Assessment Questionnaire-Disability Index (HAQ-DI) at Week 52 than those receiving adalimumab. The response rates for these endpoints were similar between the 100 mg treatment group and the adalimumab group.

Both doses of filgotinib demonstrated a consistent safety profile in the study, with no new safety signals detected. Five deaths were reported prior to Week 24: two in the placebo group, two in the 200 mg treatment group, and one in the 100 mg treatment group. Between Week 24 and Week 52, four deaths occurred: two in the 200 mg treatment group, one in the adalimumab treatment group, and one in the placebo group. Adverse events, including serious infections, herpes zoster, venous thromboembolism (VTE), and major adverse cardiovascular events (MACE), were rare during treatment, with comparable incidence rates across all groups.

The FINCH 3 study evaluated the efficacy and safety of filgotinib in patients with rheumatoid arthritis (RA) who were naïve to methotrexate (MTX). Patients were randomized to receive filgotinib 200 mg plus MTX (n=416), filgotinib 100 mg plus MTX (n=207), filgotinib 200 mg monotherapy (n=210), or MTX monotherapy (n=416). As previously reported, the filgotinib 200 mg plus MTX group met the primary endpoint, demonstrating a statistically significant difference in the proportion of patients achieving an ACR20 response at Week 24 compared with MTX monotherapy (p<0.001).

In this analysis, all treatment groups demonstrated sustained efficacy over 52 weeks based on clinical response, physical function, and radiographic progression. At Week 52, filgotinib 200 mg + MTX, filgotinib 100 mg + MTX, and filgotinib monotherapy showed statistically significant differences compared to MTX monotherapy in achieving ACR20 and ACR70 responses and disease remission. Physical function at Week 52 was significantly improved in patients receiving filgotinib 200 mg + MTX and filgotinib monotherapy compared to those receiving MTX alone, as measured by the reduction from baseline in the Health Assessment Questionnaire-Disability Index (HAQ-DI) score.

Consistent safety was observed with filgotinib monotherapy or in combination with MTX in this study, and no new safety signals were detected.

Filgotinib is a selective JAK1 inhibitor. New Drug Applications (NDAs) for its use in adult patients with moderately to severely active rheumatoid arthritis (RA) have been submitted to regulatory authorities in the United States and Japan and are currently under review. Multiple clinical studies of filgotinib for inflammatory diseases are ongoing, including the Phase 3 FINCH trial in rheumatoid arthritis, the Phase 3 DIVERSITY trial in Crohn’s disease, and the Phase 3 PENGUIN trial in psoriatic arthritis.

Reference Source: Filgotinib Demonstrates Durable Efficacy and Consistent Safety Profile at 52 Weeks in FINCH 1 and 3 Studies in Rheumatoid Arthritis