A Study of Lebrikizumab (LY3650150) in Participants With Chronic Rhinosinusitis and Nasal Polyps Treated With Intranasal Corticosteroids (CONTRAST-NP)

The main purpose of this study is to evaluate the efficacy and safety of lebrikizumab in participants with chronic rhinosinusitis and nasal polyps treated with intranasal corticosteroids. The study will last about 18 months.

Inclusion Criteria: * Physician-diagnosed chronic rhinosinusitis (CRS) with bilateral nasal polyps (NP). * Prior treatment with systemic corticosteroids (SCS) within the last 2 years (or a medical contraindication or intolerance to SCS), prior surgery for NP, or both. * Endoscopic bilateral NPS score of at least 5 out of 8, with a minimum score of 2 in each nasal cavity performed at screening and baseline. * Ongoing symptoms for at least 8 weeks prior to study entry (screening), including: 1. Nasal congestion with moderate or severe symptom severity (score 2 or 3) at screening and a weekly average severity score of at least 1 (range 0 to 3) at randomization, and 2. At least one other symptom, such as partial loss of smell (hyposmia), total loss of smell (anosmia), or anterior or posterior rhinorrhea. * Have concomitant asthma must be stable in the 3 months prior to screening using permitted regular asthma treatment. * Adolescent participants ≥12 to \