Tapering of Biologics in Inflammatory Arthritis Patients in Remission

Participants will be randomly allocated to feedback of their drug levels / antidrug antibody status to their consultant prior to tapering, or not, in a 1:1 ratio. * Those participants randomised to the group where no feedback is required will have their dosing interval doubled (from 2 to 4 weeks for certolizumab and adalimumab; from 1 to 2 weeks for etanercept). * For participants randomised to the arm where results are received by the treating clinician, advice will accompany the results. It will be made clear that this is advice only and that the ultimate treatment decisions rest with the treating clinician. Patients would be recruited at the point at which the decision is made to begin tapering their biologic. The NHS site teams will be informed which arm of the study the participant has been randomised to, as they will be made aware of patient test results. Participants will not be blinded to which intervention they receive. University of Manchester Researchers undertaking the laboratory tests and those entering study data will be blinded. The consent form, registration form, baseline CRF and baseline participant questionnaire should then be returned to the study coordinator at CfMR in the pre-paid packaging provided. A baseline DAS28 score must be provided. This should be from no more than a month before the date of consent. If this cannot be provided the patient is not eligible to take part. Recruiting teams can start to taper the patient's medication immediately after consent on to the TAPER trial. Blood samples will be taken at the following time points; * Baseline (at the point of consent, when the decision to taper is made) * 6 months after tapering starts * 12 months after tapering starts Participants in TAPER will need to have their blood samples taken the day before their next anti-TNF injection date. This means the participant will have to come in to their hospital sites at these time points for their sample. Sites will be provided with blood kits for this. These will include a phlebotomy letter, just in case the participant needs to go to a different hospital department to have their bloods taken. These will be returned to the University of Manchester is the pre-paid postage boxes provided. The researchers would like each of the follow-up visits to occur as closely to the 6 month and 12 month time points as possible. However, the researchers will accept the following visit windows; • 6 and 12 month time points; +/- 1 month The University of Manchester will return the blood results to site for participants randomised to the arm where results are returned. This will be sent via email with appropriate treatment advice, as per the information in section 4 within 4 weeks of sample receipt. The site team will receive these results by letter in advance of the follow-up visit and will have the opportunity to discuss these with the Chief Investigator, Prof. Anne Barton, in advance of the visit if required. For participants in the control arm (no feedback of results), the blood samples will be collected and tested in the same way but results will not be provided to the treating clinician.