A Study of CM326 in Patients With Chronic Rhinosinusitis With Nasal Polyps

Inclusion Criteria: * Subjects who are capable of understanding the nature of the study and voluntarily signing the ICF. * Male or female subjects, aged between 18 and 70 years old (inclusive), with a body mass index (BMI) ≥ 19 kg/m2. * Diagnosed with Chronic Rhinosinusitis With Nasal Polyps. * The total NPS score should be at least 3 points, with at least 1 point in each side of the nasal cavity. * Prior treatment with systemic corticosteroids (SCS) within two years before screening, and/or contraindicate to or intolerance to systemic corticosteroids, and/or with prior surgery to nasal polyps 6 months before the screening. * Ongoing symptoms for at least 4 weeks before screening：1) Nasal congestion/obstruction; 2) Other symptom, e.g., loss of smell or rhinorrhea. Exclusion Criteria: * Allergic or intolerant to mometasone furoate spray or CM326/placebo. * Have used of systemic immunosuppressants for inflammatory or autoimmune diseases within 8 weeks or 5 half-lives prior to randomization. * Have initiated leukotriene receptor antagonist therapy within 4 weeks prior to randomization. * have received allergen-specific immunotherapy that initiated within 3 months prior to randomization or planned to be initiated during the study period. * Have undergone nasal surgery (including nasal polypectomy) within 6 months prior to screening. * Have received medium- and short-acting systemic corticosteroids (including oral, intravenous, intramuscular corticosteroids), nasal dripping corticosteroids, traditional Chinese medicine (including systemic and local herbal products preparations) for chronic rhinosinusitis (CRS) within 4 weeks prior to screening, or long-acting systemic corticosteroids. * With concomitant asthma (including suspected diagnosis of asthma) will be excluded if they meet the following conditions: predicted FEV1 of≤ 60%, or acute exacerbation of asthma within 3 months prior to screening requiring SCS or hospitalization (\> 24 hours), or using inhaled corticosteroids (ICS) of \> 1000 μg fluticasone propionate or others at equivalent doses * With antrochoanal polyps. * With severe deviation of the nasal septum occludes at least one nostril. * With persistent rhinitis medicamentosas. * With allergic granulomatous angiitis (Churg-Strauss syndrome), granulomatosis with polyangiitis (Wegener's granulomatosis), Young's syndrome, Kartagener's syndrome or other dyskinetic ciliary syndromes, cystic fibrosis. * With acute sinusitis, nasal infection, or upper respiratory tract infection at screening. * Have symptoms or whose CT scan suggests allergic fungal sinusitis. * With malignant or benign neoplasm of nasal cavities. * With other uncontrolled serious diseases or recurrent chronic diseases. * Have severe hepatic and renal impairment. * Have received live attenuated vaccines within 12 weeks prior to randomization, or during the planned study; or have received inactivated vaccines (e.g., novel coronavirus vaccines) within 30 days prior to randomization. * With known or suspected immunosuppression, including, but not limited to, the history of invasive opportunistic infections. * Subjects who are pregnant or planning to become pregnant, or breastfeeding during the study. * With a history of large alcohol consumption or a history of drug abuse within 3 months prior to screening. * With other medical or non-medical conditions that are not suitable for participation in the study in the opinion of the investigator.