• Male or female subjects aged 12 to 17 years, inclusive, at time of Visit 1 (Screening)

• Female subjects, if sexually active, must:

∙ be practicing an effective method of birth control (e.g., prescription oral contraceptives, contraceptive injections, contraceptive patch, intrauterine device, double-barrier method \[e.g., condoms, diaphragm, or cervical cap with spermicidal foam, cream, or gel\], or male partner sterilization) before entry and throughout the study, or

‣ be surgically sterile, (have had a hysterectomy or bilateral oophorectomy, tubal ligation, or otherwise be incapable of pregnancy), or

‣ be abstinent.

• Females of child-bearing potential must have a negative urine pregnancy test at Visit 1 (Screening).

• Must have a history of CRS and be currently experiencing 2 or more of the following symptoms, 1 of which has to be either nasal congestion or nasal discharge (anterior and/or posterior nasal discharge) for equal to or greater than 12 weeks:

‣ nasal congestion

⁃ nasal discharge (anterior and/or posterior nasal discharge)

⁃ facial pain or pressure

⁃ reduction or loss of smell

• Must have endoscopic evidence of nasal mucosal disease, with edema, or purulent discharge bilaterally, or presence of bilateral disease on a prior computed tomography (CT) scan performed within 14 days of Visit 1.

• Must have at least moderate symptoms (as defined in protocol) of nasal congestion as reported by the subject, on average, for the 7-day period preceding Visit 1 (Screening) run-in.

• Must have an average morning score of at least 1.5 for congestion on the Nasal Symptom Scale (as defined in protocol) recorded on the subject diary over a 7-day period during the first 14 days of the single-blind run-in period.

• Must demonstrate an ability to correctly complete the daily diary during the run-in period to be eligible for randomization.

• Subjects with comorbid asthma must be stable, defined as no exacerbations (e.g., no emergency room visits, hospitalization, or oral or parenteral steroid use) within the 3 months before Visit 1 (Screening). Subjects who received inhaled corticosteroids are required to be on no more than a moderate dosage regimen as defined by 2021 Global Initiative for Asthma Guidelines (GINA) for 1 month before Visit 1 (Screening), and are expected to remain on it throughout the study. Subjects receiving inhaled fluticasone alone or in combination may not participate in the PK sub-study.

⁃ Subjects with aspirin exacerbated respiratory disease, who have undergone aspirin desensitization and are receiving daily aspirin therapy, must be receiving therapy for at least 6 months prior to Visit 1.

⁃ Must be able to cease treatment with intranasal steroids, inhaled corticosteroids (except permitted doses listed above for asthma) at the screening visit

⁃ If taking oral antihistamines, must be on a stable regimen for at least 2 weeks prior to Visit 1 (Screening), and agree to not change the dose of these medications until after Week 4 of the study.

⁃ Must be able to use the exhalation delivery system (EDS) correctly; all subjects will be required to demonstrate correct use with the practice EDS at Visit 1 (Screening).

⁃ Must be capable, in the opinion of the investigator, of providing assent and parent or guardian must provide informed consent to participate in the study. Subjects must sign an informed consent document indicating that they understand the purpose of and procedures required for the study and that they are willing to participate in the study.