Inclusion Criteria:

• Participant must be at least 18 years of age at the time of signing the informed consent
• Participants with bilateral sino-nasal polyposis that despite prior treatment with SCS anytime within the past 2 years; and/or who have a medical contraindication/intolerance to SCS; and/or had prior surgery for NP at Visit 1

  have

  1. An endoscopic bilateral NPS at Visit 1 of at least 5 out of a maximum score of 8 (with a minimum score of 2 in each nasal cavity) as per central assessment
  2. Ongoing symptoms (for at least 8 weeks before Visit 1) of:
     • Nasal congestion/blockade/obstruction with moderate or severe symptom severity (Score 2 or 3) at Visit 1 and a weekly average severity of greater than 1 at time of randomization (Visit 2) AND
     • Another symptom such as loss of smell, rhinorrhea (anterior/posterior)

Note: Plan to enroll at least 85% (approximately 52) participants with CRSwNP meeting following criterion:

• Participants with peripheral blood eosinophil count ≥300/mm3

• Contraceptive use should be consistent with the regulations regarding the methods of contraception for those participating in clinical studies
• Capable of giving signed informed consent

Exclusion Criteria:

• Participants with conditions/concomitant diseases making them non-evaluable at Visit 1 or for the primary efficacy endpoint (ie, NPS)
• Participants with nasal cavity malignant tumor and benign tumors (eg, papilloma, hemangioma, etc)
• Participant with historical spirometry results which showed 50% or less of predicted normal of forced expiratory volume in one second (FEV1)
• Diagnosed with; suspected of, or at high risk of endoparasitic infection, and/or use of antiparasitic drug within 2 weeks before Visit 1 or during the screening period
• History of human immunodeficiency virus infection or positive HIV 1/2 serology at Visit 1
• Known or suspected immunodeficiency
• Participants with active Tuberculosis (TB), non-tuberculous mycobacterial infection or a history of incompletely treated TB will be excluded from the study unless it is well documented by a specialist that the participant has been adequately treated and can now start treatment with a biologic agent, in the medical judgment of the Investigator and/or infectious disease specialist. Tuberculosis testing will be performed according to local guidelines if required by regulatory authorities or ethics boards, or if TB is suspected by the investigator
• Active chronic or acute infection requiring treatment with systemic antibiotics, antivirals, or antifungals within 2 weeks before Visit 1 or during the screening period
• Active malignancy or history of malignancy within 5 years before the baseline visit, except completely treated in situ carcinoma of the cervix and completely treated and resolved non-metastatic squamous or basal cell carcinoma of the skin
• Known or suspected alcohol and/or drug abuse
• History of systemic hypersensitivity or anaphylaxis to dupilumab including any excipient
• Participants meet any contraindications or warning on product labeling for budesonide nasal spray
• Severe concomitant illness(es) that, in the Investigator's judgement, would adversely affect the participant's participation in the study.
• Participants with any other medical or psychological condition including relevant laboratory or electrocardiogram (ECG) abnormalities at screening that, in the opinion of the Investigator, suggest a new and/or insufficiently understood disease, may present an unreasonable risk to the study participant as a result of his/her participation in this clinical trial, may make participant's participation unreliable, or may interfere with study assessments. The specific justification for participants excluded under this criterion will be noted in study documents (chart notes, case report form (CRF), etc)
• Planned major surgical procedure during the participant's participation in this study
• Participants who have taken:

Biologic therapy/systemic immunosuppressant/immunomodulator within 4 weeks before Visit 1 or 5 half-lives, whichever is longer.

Any investigational monoclonal antibody (mAb) within 5 half-lives or within 6 months before Visit 1 if the half-life is unknown.

Anti-immunoglobulin E therapy (omalizumab) within 4 months prior to Visit 1.

• Treatment with a live (attenuated) vaccine within 4 weeks prior to Visit 1
• Participants who are receiving leukotriene antagonists/modifiers within 4 weeks before V1 or 5 half-lives, whichever is longer, unless patient is on a continuous treatment for at least 4 weeks before Visit 1
• Initiation of allergen immunotherapy within 3 months prior to Visit 1 or a plan to begin therapy or change its dose during the run-in or randomized treatment period
• Participants who have undergone any intranasal and/or sinus surgery (including polypectomy) within 6 months prior to Visit 1 or sino-nasal surgery changing the lateral wall structure of the nose making the evaluation of NPS impossible
• Use of any prohibited medications and procedures during screening period or planned use during screening or study treatment period
• Either intravenous immunoglobulin (IVIG) therapy and/or plasmapheresis within 4 weeks before Visit 1
• Current participation in any clinical trial of an investigational drug or device or participation within 3 months before V1 or 5 half-lives of the investigational compound, whichever is longer
• Participation in a prior dupilumab clinical study or have been treated with commercially available dupilumab
• Patients with any of the following result at the screening visit (Visit 1):

Positive (or indeterminate) hepatitis B surface antigen (HBsAg) or, Positive total Hepatitis B core antibody (HBc Ab) confirmed by positive hepatitis B virus (HBV) DNA or, Positive HCV Ab confirmed by positive hepatitis C Virus (HCV) RNA.

• noninvestigational medicinal product(NIMP) noncompliance at Visit 2 (<80%)
• Any condition that could make the participant noncompliant with the study procedures and daily assessment in the e-diary
• Individuals accommodated in an institution because of regulatory or legal order; prisoners or participants who are legally institutionalized.
• Participants not suitable for participation, whatever the reason, as judged by the Investigator, including medical or clinical conditions, or participants potentially at risk of noncompliance to study procedures
• Participants are employees of the clinical study site or other individuals directly involved in the conduct of the study, or immediate family members of such individuals
• Sensitivity to any of the study interventions, or components thereof, or drug or other allergy that, in the opinion of the Investigator, contraindicates participation in the study