TY - JOUR T1 - Comment on ‘Sustained discontinuation of infliximab with a raising-dose strategy after obtaining remission in patients with rheumatoid arthritis: the RRRR study, a randomised controlled trial’ by Tanaka <em>et al</em> JF - Annals of the Rheumatic Diseases JO - Ann Rheum Dis SP - e172 LP - e172 DO - 10.1136/annrheumdis-2019-216557 VL - 80 IS - 11 AU - Lea C Berkhout AU - Merel J l'Ami AU - Gerrit Jan Wolbink AU - Theo Rispens Y1 - 2021/11/01 UR - http://ard.bmj.com/content/80/11/e172.abstract N2 - We have read with interest the paper of Tanaka et al 1 and support the need for a more personalised approach in dosing regimens of tumour necrosis factor (TNF) inhibitors.2 They adjusted infliximab dose based on TNF concentrations at baseline, under the assumptions that baseline TNF concentrations can be accurately measured, and that high disease activity (ie, more inflammation) is associated with higher TNF concentrations. However, several factors argue against these assumptions, which we would like to add to the study by Tanaka et al. These factors might explain the absence of an association between TNF concentrations and treatment response.First, the quantification of TNF at baseline is in fact challenging: TNF is an unstable molecule with … ER -