Inclusion Criteria:

• Patients with bilateral sinonasal polyposis that despite prior treatment with systemic corticosteroids (SCS) anytime within the past 2 years; and/or have a medical contraindication / intolerance to SCS; and/or had prior surgery for NP at the screening visit, have:
• An endoscopic bilateral NPS of at least 5 out of a maximum score of 8 (with a minimum score of 2 in each nasal cavity).
• Ongoing symptoms (for at least 8 weeks prior to V1) of nasal congestion/blockage/obstruction with moderate or severe symptom severity (score 2 or 3) at V1 and a weekly average severity of greater than 1 at the time of randomization (V2), and another symptom such as loss of smell, rhinorrhea (anterior/posterior).
• Signed written informed consent.

Exclusion Criteria:

• Patients <18 years of age.
• Patient who has previously been treated in dupilumab studies.
• Patient who has taken:
• Biologic therapy/systemic immunosuppressant to treat inflammatory disease or autoimmune disease (eg, rheumatoid arthritis, inflammatory bowel disease, primary biliary cirrhosis, systemic lupus erythematosus, multiple sclerosis, etc.) within 2 months before V1 or 5 half-lives, whichever is longer.
• Any experimental monoclonal antibody (mAB) within 5 half-lives or within 6 months before V1 if the half-life is unknown.
• Anti-immunoglobulin E (IgE) therapy (omalizumab) within 130 days prior to V1.
• Patients who are receiving leukotriene antagonists/modifiers at V1 unless they are on a continuous treatment for at least 30 days prior to V1.
• Initiation of allergen immunotherapy within 3 months prior to V1 or a plan to begin therapy or change its dose during the run-in period or the randomized treatment period.
• Patients who have undergone any intranasal and/or sinus surgery (including polypectomy) within 6 months prior to V1.
• Patients who have had a sinonasal or sinus surgery changing the lateral wall structure of the nose making impossible the evaluation of NPS.
• Patients with conditions/concomitant diseases making them nonevaluable at V1 or for the primary efficacy endpoint such as:
• Antrochoanal polyps;
• Nasal septal deviation that would occlude at least one nostril;
• Acute sinusitis, nasal infection or upper respiratory infection;
• Ongoing rhinitis medicamentosa;
• Allergic granulomatous angiitis (Churg-Strauss syndrome), granulomatosis with polyangiitis (Wegener's granulomatosis), Young's syndrome, Kartagener's syndrome or other dyskinetic ciliary syndromes, concomitant cystic fibrosis;
• Radiologic suspicion, or confirmed invasive or expansive fungal rhinosinusitis.
• Patients with nasal cavity malignant tumor and benign tumors (eg, papilloma, blood boil, etc).
• Patients with forced expiratory volume in 1 second (FEV1) 50% or less (of predicted normal).
• Patients receiving concomitant treatment prohibited in the study.
• Treatment with a live (attenuated) vaccine within 12 weeks before the baseline visit.
• History of human immunodeficiency virus (HIV) infection or positive HIV serology at screening.
• Positive with hepatitis B surface antigen (HBsAg) or hepatitis C antibody at the screening visit.
• Active chronic or acute infection requiring systemic treatment within 2 weeks before the baseline visit.
• Known or suspected history of immunosuppression.
• Pregnant or breastfeeding women, or women planning to become pregnant or breastfeed during the study.
• Women unwilling to use adequate birth control, if of reproductive potential and sexually active.