Nasal Polyps Clinical Trials

• 1 Inclusion criteria (all must be fulfilled)

⁃ At the time when the patient started biological treatment, they must have fulfilled the EPOS criteria for initiation of biologic treatment (REF EPOS):

• Fulfil the criteria for CRSwNP

• Presence of bilateral polyps in a patient

• Had ESS (sinus surgery) (exceptional circumstances excluded)

• Fulfil at least three of the following five criteria Evidence of type 2 inflammation Need for (and treated with) systemic corticosteroids or contraindication to these SNOT-22 score of 40 or above Significant loss of smell Asthma needing regular inhaled corticosteroids

⁃ To enter this study, the patient must be:

• Above 18 years of age

• Currently be in treatment with either Dupilumab (300 mg) or Mepolizumab (100 mg) with treatment every fourth week. This treatment should have been stable/unchanged for at least three months.

• Within the latest year, the patient must at all times have scored all the below symptoms of CRS five or below on a VAS scale from 0 - 10 - Doing this, it is according to the EPOS defined as controlled disease. The items are: nasal blockage, rhinorrhea/postnasal drip, facial pain/pressure, smell, sleep disturbance or fatigue) Please view appendix 2.

• Within the latest year the nasal endoscopy cannot have showed polyp score of more than 1+1 out of 4+4, further, no thick secretions or general oedema must have been present.

• Within the latest year the patient is not allowed to have had ESS or rescue treatment for their CRSwNP (antibiotics or systemic steroids)

• The patient must be able to understand Danish and able to sign an informed content.