Westhovens R, Rigby WFC, van der Heijde D, et al. - In this study, the efficacy and safety of the Janus kinase-1 inhibitor filgotinib in patients with active rheumatoid arthritis (RA) with limited or no prior methotrexate (MTX) exposure were explored. Researchers designed 52-week, phase 3, multicentre, double-blind clinical trial investigating once-daily oral filgotinib in 1252 patients with RA randomized 2:1:1:2 to filgotinib 200 mg with MTX (FIL200 +MTX), filgotinib 100 mg with MTX (FIL100 +MTX), filgotinib 200 mg monotherapy (FIL200), or MTX. Signs and symptoms and physical function were significantly improved by FIL200+MTX and FIL100+MTX in patients with active RA and limited or no prior MTX exposure; FIL200 monotherapy did not have a superior ACR20 response rate vs MTX. Compared with MTX, filgotinib was well tolerated, with acceptable safety.