Complete Remission After Treatment With Biologics for Nasal Polyps

11 Protocol Synopsis 11.1. EU trial number and full trial title: 2024- 5196285-25-00 English title: Complete remission study Subtitle: Discontinuation of Mepolizumab or Dupilumab after at least 12 months without symptoms in patients with severe Chronic rhinosinusitis with polyps - a National Danish RCT study. 11.2. Rationale Specify background and hypothesis of the trial. The Danish Medicines Council has decided that well-controlled patients with nasal polyps should try to cease the medication after two years of treatment with biologics (Mepolizumab or Dupilumab). The investigators find this better to do in a RCT. Based on the experience from asthma patients this could be done in some patients without the symptoms reoccur. 11.3. Objective Specify the main and secondary objectives of the trial. The main objective is to find the percentage of patients in complete remission (no or few symptoms) who can cease the biologic treatment and keep being in remission. The secondary objective is to observe if one or the other drug is more likely to give this result. 11.4. \& 11.5 Main and secondary trial endpoints: The main endpoint is to monitor the percentage of patients who do not have recurrence of their sino-nasal symptoms when they cease medicine. This is evaluated at baseline and after 12,26,38,52 weeks, however, the patients can contact the investigators at any time if symptoms reoccur. A control group is included and it is assumed that patients kept on treatment will keep being in complete remission. No adverse effects are expected, thus no new medication is started. 11.6. Trial design: Non-blinded, prospective RCT. Half the included patients will keep their treatment unchanged (control-group) the other half will stop the biological treatment (everything else unchanged). Every individual participant will have a 52-week follow-up period. If a participant in the trial group gets symptoms and feel partly uncontrolled they will start treatment again with same drug, dose and interval as before the cease. 11.7. Trial population: Patients over 18 years of age, who have been on hospital administrated biologic treatment for at least 1½ year and have been in remission for at least a year. 11.8. Interventions: The participants are randomized into two groups: one group (33 patients) will be the control group with no change in their treatment, the other group (33 patients) will cease treatment. 11.9. Ethical considerations. The investigators have very few ethical concerns by conducting this study. It is highly unlikely that any side effects will occur, thus there is no suspicion that reducing dose of biologics gives risks of side effects. Further, none of the examinations or questionnaires are add-on to the examinations that the patients must go through when being in biologic treatment. The investigators only concern is that some patients will experience recurrence of sino-nasal and/or asthma symptoms when stopping the biologic medicine. However, there is a plan for handling this safely. Lastly, it should also be kept in mind that the Danish medicines council recommends trying to stop the treatment, thus the investigators find it better to do this under RCT conditions.