Filgotinib (FIL) is a Janus kinase preferential inhibitor, classified as a targeted synthetic disease-modifying anti-rheumatic drug (tsDMARD). It is approved for patients with rheumatoid arthritis (RA) who have failed treatment with methotrexate (MTX), a conventional synthetic DMARD (csDMARD). Randomized controlled trials (RCTs) investigating 100 and 200 mg doses of FIL + MTX have demonstrated rapid effects in reducing disease activity, pain, and fatigue and improving functional outcomes compared with MTX monotherapy or adalimumab (a biologic) + MTX. FIL’s efficacy in reducing disease activity and improving functional outcomes was sustained in the long-term (3 years), while also minimizing radiographic progression. In particular, 200 mg FIL + MTX significantly reduced radiographic progression uncoupled from disease activity, outperforming adalimumab + MTX in patients with medium or high disease activity. Adverse events were similar among FIL, MTX, and adalimumab over 52 weeks in RCTs, with a consistent safety profile in the long term (> 8 years). FIL persistence rates were generally high, regardless of dose. Evidence from real-world observational studies complements and underscores the effectiveness and safety of FIL demonstrated in RCTs. These findings support FIL’s potential as a therapeutic option in the management of RA. Guidelines currently recommend a starting dose of 200 mg FIL ± MTX; a 100 mg starting dose can be used if the patient is elderly (Europe); at increased risk of venous thromboembolism, major adverse cardiovascular events or malignancy (Europe); or has impaired renal function (Japan). Furthermore, patients should only initiate FIL after inadequate response to MTX or other csDMARDs. In clinical practice, there may be additional considerations that could impact outcomes, including persistence and variations in patient profiles and treatment backgrounds. Future results from ongoing studies can be expected to provide further insights into the long-term effectiveness, such as joint outcomes and safety of FIL, in the real-world context. Graphical abstract available for this article. Filgotinib is an oral medication for rheumatoid arthritis. It is a Janus kinase inhibitor that blocks a protein involved in long-term inflammation. Patients with rheumatoid arthritis are usually first treated with methotrexate, a conventional medication. Filgotinib is for patients whose methotrexate or other similar treatments did not work well enough, or for those who cannot tolerate these treatments. Clinical trials have shown that filgotinib can provide better, faster effects, including pain relief, than methotrexate alone. Additionally, filgotinib helps prevent joint damage and improves movement. Most people can take filgotinib without serious side effects; in clinical trials, filgotinib had similar side effects as methotrexate. Therefore, patients could continue filgotinib without stopping treatment early. While clinical trials are conducted in more controlled environments, studies of filgotinib in real-world settings showed similar effectiveness and safety. Currently, filgotinib is approved for treatment of rheumatoid arthritis in the European Union, UK, Japan, Taiwan, South Korea and Singapore. In Europe and Japan, the recommended starting dose of filgotinib is 200 mg, either alone or with methotrexate. A lower starting dose may be needed for certain patients; 100 mg could be advised for the elderly or those at higher risk of blood clots, heart issues or cancer, or with kidney problems. Other factors that may affect how well filgotinib works include prior treatments and other conditions patients may have besides rheumatoid arthritis. Further research will shed more light on real-life results with filgotinib in the future.
Tanaka et al. (Sat,) studied this question.