The treatment group will receive dupilumab at 300mg SC Q2weeks. The first dose will be administered via subcutaneous injection in clinic at baseline. Subjects will self-administer study drug (dupilumab 300 mg) subcutaneous every 2 weeks after initial dosing at visit 2.

Monoclonal antibody blocking interleukin 4 and interleukin 13

Non-contrast sinus computed tomography (CT) scans will be obtained at baseline and 3 month follow-up to provide 1mm cuts that can be formatted in coronal, sagittal, and axial planes. Volumetric analysis of the OC will be performed utilizing equally spaced coronal CT images per our previously described protocols. Total volume of the segmented 3-D olfactory cleft space will be calculated, as well as the volume of air within that space. The percent opacification will be defined as [1-(total volume of air/total volume of olfactory cleft)] multiplied by 100. Sinus opacification will be quantified using the Lund-Mackay CT scale.

Subjects will have sinonasal endoscopy at baseline and every follow up visit. This procedure allows visual inspection of the sinus mucosal lining and grading of polyps, including the olfactory cleft. Results for each side will be recorded separately and combined for a final Olfactory Cleft Endoscopy Scale (OCES) that ranges from 0-20, with higher scores representing increased disease severity.

Under endoscopic guidance, a 1 × 2-cm Leukosorb filter paper (Pall Scientific, Port Washington, NY) strip will be placed into the olfactory cleft of each side, and kept in place for 3 minutes, as described in earlier studies. This will be done at baseline, 2 weeks, and 3 months. Olfactory cleft mucus inflammatory cytokine levels will be detected using commercially available LegendPlex Th2 Cytometric Bead Array (BioLegend, San Diego, CA) following the manufacturer's recommended protocol. This panel will include IL4, IL13, IL5 cytokines (among others). The assay will be carried out according to manufacturers' instructions and as previously described. The samples will be read on a Guava easyCyte 8HT flow cytometer (EMD Millipore) and analysis performed with LegendPlex software. Total IgE will be quantified via ELISA (GenWay Biotech. Inc, San Diego, CA).

Quantitative psychophysical olfactory testing will be performed using the "Sniffin' Sticks" test (Burghardt, Wedel, Germany). Testing will be performed by trained clinical research coordinators who routinely perform objective olfactory testing and will be done in a blinded fashion. This commercially available test battery measures odor threshold (OT), odor discrimination (OD) and odor identification (OI). The results will be combined for an overall TDI score. TDI will be correlated with OC IL13 levels.