Efficacy and Safety of Depemokimab (GSK3511294) in Participants With Chronic Rhinosinusitis With Nasal Polyps (ANCHOR-1)

Inclusion criteria:

• Participants with 18 years of age and older inclusive, at the time of signing the informed consent.
• Endoscopic bilateral NP score of at least 5 out of a maximum score of 8 (with a minimum score of 2 in each nasal cavity) assessed by the investigator.
• Participants who have had at least one of the following at Visit 1: Previous nasal surgery for the removal of NP; have used at least three consecutive days of systemic corticosteroids in the previous 2 years for the treatment of NP; medically unsuitable or intolerant to systemic corticosteroid.
• Participants (except for those in Japan) must be on daily treatment with intranasal corticosteroids (INCS) (including intranasal liquid steroid wash/douching) for at least the 8 weeks immediately prior to screening.
• Participants presenting with severe NP symptoms defined as symptoms of nasal congestion/blockade/obstruction with moderate or severe severity and loss of smell or rhinorrhea (runny nose) based on clinical assessment by the investigator.
• Presence of symptoms of chronic rhinosinusitis as described by at least 2 different symptoms for at least 12 weeks prior to Visit 1, one of which should be either nasal blockage/obstruction/congestion or nasal discharge (anterior/posterior nasal drip), plus facial pain/pressure and/or reduction or loss of smell.
• Male or eligible female participants.

Exclusion criteria:

• As a result of medical interview, physical examination, or screening investigation the physician responsible considers the participant unfit for the study.
• Cystic fibrosis.
• Antrochoanal polyps.
• Nasal cavity tumor (malignant or benign).
• Fungal rhinosinusitis.
• Severe nasal septal deviation occluding one nostril preventing full assessment of nasal polyps in both nostrils
• Participants who had a sino-nasal or sinus surgery changing the lateral wall structure of the nose making impossible the evaluation of nasal polyp score.
• Acute sinusitis or upper respiratory tract infection (URTI) at screening or in 2 weeks prior to screening.
• Ongoing rhinitis medicamentosa (rebound or chemical induced rhinitis).
• Participants who have had an asthma exacerbation requiring admission to hospital within 4 weeks of screening.
• Participants who have undergone any intranasal and/or sinus surgery (for example [e.g.], polypectomy, balloon dilatation or nasal stent insertion) within 6 months prior to Visit 1; nasal biopsy prior to Visit 1 for diagnostic purposes only is excepted.
• Participants where NP surgery is contraindicated in the opinion of the Investigator.
• Participants with other conditions that could lead to elevated eosinophils such as hyper-eosinophilic syndromes including (but not limited to) Eosinophilic granulomatosis with polyangiitis (EGPA) (formerly known as Churg-Strauss Syndrome) or Eosinophilic Esophagitis.
• Participants with a known, pre-existing parasitic infestation within 6 months prior to Visit 1.
• A known immunodeficiency (e.g. human immunodeficiency virus [HIV]), other than that explained by the use of corticosteroids (CSs) taken as therapy for asthma.
• A current malignancy or previous history of cancer in remission for less than 12 months prior to screening.
• Liver Disease: Alanine aminotransferase (ALT) >2 times Upper limit of normal (ULN); Total bilirubin >1.5 times ULN (isolated bilirubin >1.5 times ULN is acceptable if bilirubin is fractionated and direct bilirubin less than [<]35 percent [%]); Cirrhosis or current unstable liver or biliary disease per investigator assessment defined by the presence of ascites, encephalopathy, coagulopathy, hypoalbuminemia, esophageal or gastric varices, persistent jaundice.
• Participants who have known, pre-existing, clinically significant cardiac, endocrine, autoimmune, metabolic, neurological, renal, gastrointestinal, hepatic, hematological or any other system abnormalities that are uncontrolled with standard treatment.
• Participants with current diagnosis of vasculitis. Participants with high clinical suspicion of vasculitis at screening will be evaluated and current vasculitis must be excluded prior to enrollment.
• Hypersensitivity: Participants with allergy/intolerance to the excipients of depemokimab (GSK3511294) in a monoclonal antibody, or biologic.
• Participants that, according to the investigator's medical judgment, are likely to have active Coronavirus Disease-2019 (COVID-19) infection must be excluded. Participants with known COVID-19 positive contacts within the past 14 days must be excluded for at least 14 days following the exposure during which the participant should remain symptom-free. Reported smell/ taste complications from COVID-19 must be used as exclusion.
• Participants that have been exposed to ionizing radiation in excess of 10 millisievert (mSv) above background over the previous 3-year period as a result of occupational exposure or previous participation in research studies.
• Previously participated in any study with mepolizumab, reslizumab, or benralizumab and received study intervention (including placebo) within 12 months prior to Visit 1.
• Women who are pregnant or lactating or are planning on becoming pregnant during the study.