May 5, 2021 Therapeutic drug monitoring, half-dosing may not be ready for prime-time Therapeutic drug monitoring (TDM) for patients with immune-mediated inflammatory diseases did not lead to better clinical remission rates, while routine dose reduction of anti-rheumatic drugs for patients with rheumatoid arthritis (RA) in remission offered modest benefits, according to two Norwegian trials. In the NOR-DRUM Part A trial, clinical remission at week 30 was achieved in 50.5% of 198 patients with TDM versus 53% of 200 patients in the standard therapy group, for an adjusted difference of 1.5% (95% CI −8.2% to 11.1%, P=0.78), reported Silje Watterdal Syversen, MD, PhD, of Diakonhjemmet Hospital in Oslo, and co-authors. In the ARCTIC REWIND trial, disease flare occurred in 25% of 77 patients in the half-dose conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) group versus 6% in the stable-dose csDMARD group for a risk difference of 18% (95% CI 7%-29%), reported Siri Lillegraven, MD, MPH, PhD, also of Diakonhjemmet Hospital, and co-authors.