A Study of the Efficacy and Safety of Brensocatib in Participants With Chronic Rhinosinusitis Without Nasal Polyps (CRSsNP)

Inclusion Criteria:

• Participants who have at least a 12-week history before Screening Visit of CRSsNPand confirmed by endoscopy at Visit 1 (Screening).

• Participants must have a NCS of ≥2 at Visit 1 (Screening Visit) and Visit 2 (weeklyaverage score).

• Participants must have sTSS (nasal congestion [NC], anterior/posterior rhinorrhea,facial pain/pressure) ≥5 at Visit 1 (Screening) and at Visit 2 (Baseline) (averagescore in the week prior to randomization).

• Participants who have at least 1 of the 3 following features:

1. Previous sinonasal surgery for CRS, including but not limited to fenestratedendoscopic sinus surgery and balloon sinuplasty.

2. Received medical treatment with systemic corticosteroids (SCS) to treatsymptoms of CRS as defined by any dose and duration within 1 year of ScreeningVisit or intolerance/contraindication to SCS.

3. Received a course of antibiotics to treat symptoms of CRS within 1 year beforethe Screening Visit.

• Participants who have a blood eosinophil count ≤750 cells/microliter (μL) at Visit 1 (Screening).

• Participants who have bilateral inflammation of paranasal sinuses in the CT scanperformed during Screening and bilateral ethmoid and/or maxillary opacificationbefore randomization as confirmed by the central reader.

• Participants who have a SNOT-22 score of ≥20 at Visit 1 (Screening) and Visit 2 (Baseline).

• Participants who have received a stable daily dose regimen of MFNS for at least 4weeks before Visit 2 (Baseline).

Exclusion Criteria:

• Diagnosis of unilateral or bilateral chronic rhinosinusitis with nasal polyps (CRSwNP).

• Clinical diagnosis of cystic fibrosis (CF) or primary ciliary dyskinesia.

• Scheduled sinus surgery at any time during the study.

• Participants who have had nasal surgery within 4 weeks before Visit 1 (Screening)and during the Screening Period.

• Significant oral maxillofacial structural abnormalities or severe septal deviation.

• Participants with radiological suspicion or confirmed invasive fungalrhinosinusitis, odontogenic sinusitis, osteomas, or nasal tumors.

• Participants with acute change in symptoms consistent with acute rhinosinusitis.

• Participants with seasonal allergic rhinitis whose symptoms coincide with thetreatment period of the study.

• Participants with moderate to severe atopic dermatitis requiring treatment with highpotency topical steroids or topical calcineurin inhibitors or biologics.

• Clinical diagnosis of Papillon-Lefèvre syndrome. Note: Other inclusion/exclusioncriteria may apply.