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Effect of Mepolizumab in Severe Bilateral Nasal Polyps

A Randomised, Double-blind, Parallel Group PhIII Study to Assess the Clinical Efficacy and Safety of 100 mg SC Mepolizumab as an Add on to Maintenance Treatment in Adults With Severe Bilateral Nasal Polyps - SYNAPSE (StudY in NAsal Polyps Patients to Assess the Safety and Efficacy of Mepolizumab)

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03085797
Enrollment
414
Registered
2017-03-21
Start date
2017-05-25
Completion date
2019-12-11
Last updated
2026-07-22

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Nasal Polyps

Keywords

SB240563, Nasal Polyps, Mepolizumab, Phase 3, Parallel group, Efficacy

Brief summary

Nasal polyps (NP) has long been known as chronic inflammatory disease of the nasal mucosa. This disease is characterized by the presence of polyps in the upper nasal cavity, originating from within the ostiomeatal complex. The presence of polyps can cause long-term symptoms such as prominent nasal obstruction, post-nasal drip, loss of smell, and discharge. Mepolizumab (SB240563) is an Immunoglobulin G 1 \[IgG1\], kappa humanized monoclonal antibody (mAB) that blocks human interleukin-5 (hIL-5) from binding to the interleukin-5 (IL-5) receptor complex expressed on the eosinophil cell surface and thus inhibits signaling. Neutralization of IL-5 with mepolizumab has been shown to reduce blood, sputum and tissue eosinophils and hence is assumed to be a treatment option in a number of eosinophilic diseases including NP. The aim of this randomized, double-blind, parallel group, phase 3 (PhIII) study is to assess the clinical efficacy and safety of 100 milligram (mg) subcutaneous (SC) mepolizumab as an add on to maintenance treatment in adults with severe bilateral NP. The study will include a 4-week run in period followed by randomization to a 52-week treatment period. Participants will receive mepolizumab 100 mg or placebo SC by the investigator or delegate via a pre-filled safety syringe every 4 weeks for 52 weeks. Throughout the entire study period (run in + treatment period + follow up), participants will receive a standard of care (SoC) for NP which consists of daily mometasone furorate (MF) nasal spray, and if required, saline nasal douching, occasional short courses of high dose oral corticosteroids (OCS) and/or antibiotics. The treatment period will consist of thirteen, 4-weekly doses of mepolizumab or placebo. In addition, up to the first 200 randomized participants will be followed up every other month for up to a further 6 months after the Visit 15 (7 months post last dose) in order to assess maintenance of response and to validate a physiological model derived from the previous Phase 2 study. Approximately 400 participants will be randomized (200 participants per treatment arm) in to the study. Total duration of the study will be 76 weeks for first 200 randomized participants and 52 weeks for remainder of participants who are not participating in the 6 months no treatment follow up.

Interventions

DRUGMepolizumab

Mepolizumab injection 100 mg/millilitre (mL) is a clear to opalescent, colorless to pale yellow to pale brown sterile solution for SC injection in a single-use, safety syringe.

DRUGPlacebo

Placebo is a clear to opalescent, colorless sterile solution for SC injection in a single-use, safety syringe.

DRUGMometasone furoate

All participants will receive mometasone furoate usually 400 micrograms (mcg), 2 actuations (50 mcg/actuation) in each nostril twice daily. Intolerant participants will use 200g (2 actuations \[50 g/actuation\] in each nostril once daily).

Sponsors

GlaxoSmithKline
Lead SponsorINDUSTRY
CRF Health
CollaboratorINDUSTRY
Bristol-Myers Squibb
CollaboratorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Investigator)

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* 18 years of age and older inclusive, at the time of signing the informed consent. * Body weight greater or equal to 40 kilogram (kg). * Male or female participants (with appropriate contraceptive methods) to be eligible for entry into the study. To be eligible for entry into the study, woman of childbearing potential (WOCBP) must commit to consistent and correct use of an acceptable method of birth control from the time of consent, for the duration of the trial, and for 105 days after last study drug administration. * Participants who have had at least one previous surgery in the previous 10 years for the removal of NP. NP Surgery is defined as any procedure involving instruments with resulting incision (cutting open) and removal of polyp tissue from the nasal cavity (polypectomy). For the purpose of inclusion into this study, any procedure involving instrumentation in the nasal cavity resulting in dilatation of the nasal passage such as balloon sinuplasty, insertion of coated stents or direct injection of steroids or other medication without any removal of NP tissue is not accepted. * Participants with bilateral NP as diagnosed by endoscopy or computed tomography (CT) scan. * Presence of at least two of the following symptoms one of which should be either nasal blockage/obstruction/congestion or nasal discharge (anterior/posterior nasal drip) and either nasal discharge (anterior/posterior nasal drip); facial pain/pressure; reduction or loss of smell for at least 12 weeks prior to screening. * Participants with severe NP symptoms defined as an obstruction VAS symptom score of \>5. * Severity consistent with a need for surgery as described by: 1. Participants with an overall VAS symptom score \>7, 2. Participants with an 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). * Treatment with intranasal corticosteroids (INCS) for at least 8 weeks prior to screening. * Capable of giving signed informed consent

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 * Eosinophilic granulomatosis with polyangiitis (also known as churg strauss syndrome), young's, kartagener's or dyskinetic ciliary syndromes. * Antrochoanal polyps * Nasal septal deviation occluding one nostril * Acute sinusitis or upper respiratory track 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 polypectomy, balloon dilatation or nasal stent insertion) within 6 months prior Visit 1. * Participants where NP surgery is contraindicated in the opinion of the Investigator. * Participants with a known medical history of human immunodeficiency virus (HIV) infection. * Participants with a known, pre-existing parasitic infestation within 6 months prior to Visit 1. * Participants who are currently receiving, or have received within 3 months (or 5 half lives - whatever is the longest) prior to first mepolizumab dose, chemotherapy, radiotherapy or investigational medications/therapies. * Participants with a history of sensitivity to any of the study medications, or components thereof or a history of drug or other allergy that, in the opinion of the investigator or GSK medical monitor, contraindicates their participation. Aspirin-sensitive participants are acceptable. * Participants with a history of allergic reaction to anti-IL-5 or other monoclonal antibody therapy. * Participants on a waiting list for NP surgery while at screening * Participants that have taken part in previous mepolizumab, reslizumab, dupilumab or benralizumab studies. * Use of systemic corticosteroids (including oral corticosteroids) or corticosteroid nasal solution (intranasal corticosteroid is accepted) within 4 weeks prior to Screening or planned use of such medications during the double-blind period. * INCS dose changes within 1 month prior to screening. * Treatments with biological or immunosuppressive treatment (other than omalizumab) treatment within 5 terminal phase half lives of Visit 1. * Omalizumab treatment in the 130 days prior to Visit 1. * Commencement of leukotriene antagonist treatment less than 30 days prior to Visit 1. * Allergen immunotherapy within the previous 3 months. * Women who are pregnant or lactating or are planning on becoming pregnant during the study. * Participants who currently smoke or have smoked in the last 6 months. * Any participant who is considered unlikely to survive the duration of the study period or has any rapidly progressing disease or immediate life-threatening illness (e.g. cancer). In addition, any participant who has any other condition (e.g. neurological condition) that is likely to affect respiratory function should not be included in the study. * Participants who have known, pre-existing, clinically significant endocrine, autoimmune, cardiovascular, metabolic, neurological, renal, gastrointestinal, hepatic, hematological or any other system abnormalities that are uncontrolled with standard treatment. * Immunocompromized, other than that explained by the use of corticosteroids taken as therapy. * A current malignancy or previous history of cancer in remission for less than 12 months prior to Screening. Participants with successfully treated basal cell carcinoma, squamous cell carcinoma of the skin, or cervical carcinoma in situ, with no evidence of recurrence may participate in the study. * Current active liver or biliary disease (with the exception of gilbert's syndrome or asymptomatic gallstones or otherwise stable chronic liver disease per investigator assessment). * Corrected QT interval (QTc) \>450 milliseconds (msec) or QTc \>480 msec in participants with bundle branch block at visit 1. * A known or suspected history of alcohol or drug abuse within 2 years prior to Screening (Visit 1) that in the opinion of the investigator would prevent the participant from completing the study procedures. * An investigator, sub-investigator, study coordinator, employee of a participating investigator or study site, or immediate family member of the aforementioned that is involved in this study. * In the opinion of the investigator, any participant who is unable to read and/or would not be able to complete a questionnaire.

Design outcomes

Primary

MeasureTime frameDescription
Change From Baseline in Total Endoscopic Nasal Polyps Score at Week 52Baseline (Day 1) and Week 52Independent reviewers, blinded to treatment, reviewed image recordings of nasal endoscopies to determine total endoscopic NP score based on NP size. The right and left nostrils were scored from 0 to 4 (0 = No polyps; 1 = Small polyps in the middle meatus not reaching below the inferior border of the middle concha; 2 = Polyps reaching below the lower border of the middle turbinate; 3 = Large polyps reaching the lower border of the inferior turbinate or polyps medial to the middle concha; and 4 = Large polyps causing complete obstruction/congestion of the inferior meatus). The total score is the sum of the right and left nostril scores and ranges from 0 to 8, higher scores indicate greater disease severity. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. Baseline was defined as Day 1 value. Change from Baseline = Post-baseline value minus Baseline value.
Change From Baseline in Nasal Obstruction Visual Analog Scale (VAS) Score During the 4 Weeks Prior to Week 52Baseline and Weeks 49 to 52Participants rated individual (nasal obstruction, nasal discharge, mucus in the throat, loss of smell, facial pain) and overall symptoms on a visual analog scale (VAS) using an electronic diary (eDiary). Captured scores ranged between 0 (none) and 100 (as bad as you can imagine), final scores derived from the electronically captured scores by dividing by 10. The final nasal obstruction VAS score ranged between 0 and 10, with higher scores indicating greater disease severity. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. The average of daily scores in 4-weekly intervals were calculated and data is presented for Weeks 49-52. Baseline was defined as the average score from the 7 days of eDiary data collected prior to Day 1. Change from Baseline = Post-baseline value minus Baseline value.

Secondary

MeasureTime frameDescription
Percentage of Participants With Nasal Surgery Over TimeWeeks 8, 16, 24, 32, 40, 48 and 52The percentage of participants with nasal surgery over time (by Weeks 8, 16, 24, 32, 40, 48 and 52) was derived from Kaplan-Meier time-to-event analyses for the event 'first nasal surgery'. Nasal surgery was defined as any procedure involving instruments resulting in incision and removal of tissue (polypectomy) in the nasal cavity. Time to first nasal surgery was defined as (Date of first nasal surgery - Date of first dose of study treatment) + 1. Percentage of participants with nasal surgery over time (by Weeks 8, 16, 24, 32, 40, 48 and 52) and corresponding 95% CI have been presented, calculated using the Kaplan-Meier method. Analysis included surgeries occurring up to Week 52, reported on-treatment and those reported after early discontinuation from IP by participants who remained in the study.
Change From Baseline in Overall VAS Score During the 4 Weeks Prior to Week 52Baseline and Weeks 49 to 52Participants rated individual (nasal obstruction, nasal discharge, mucus in the throat, loss of smell, facial pain) and overall symptoms on a visual analog scale using an eDiary. Captured scores ranged between 0 (none) and 100 (as bad as you can imagine), final scores derived from the electronically captured scores by dividing by 10. The final overall VAS score ranged between 0 and 10, with higher scores indicating greater disease severity. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. The average of daily scores in 4-weekly intervals were calculated and data is presented for Weeks 49-52. Baseline was defined as the average score from the 7 days of eDiary data collected prior to Day 1. Change from Baseline = Post-baseline value minus Baseline value.
Change From Baseline in Sino-nasal Outcome Test (SNOT)-22 Total Score at Week 52Baseline (Day 1) and Week 52The SNOT-22 is a 22-item self-reported questionnaire developed to measure symptoms and impacts related to chronic rhinosinusitis. The 22 questions are self-completed by participants based on their recall of their symptoms over the previous 2 weeks using a 6-point rating scale (0 = Not present/no problem; 1 = Very mild problem; 2 = Mild or slight problem; 3 = Moderate problem; 4 = Severe problem; 5 = Problem as "bad as it can be"). Scores for each question are summed to derive the total score. The SNOT-22 total score ranges from 0 to 110, with higher scores representing worse quality of life. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. Baseline was defined as Day 1 value. Change from Baseline = Post-baseline value minus Baseline value.
Percentage of Participants Requiring at Least One Course of Systemic Steroids for Nasal Polyps up to Week 52Up to Week 52The number of courses of systemic steroids received by participants were recorded. For the purpose of this study, a course of systemic corticosteroid separated by less than 7 days was considered as a continuation of the same course. Percentage of participants requiring at least one course of systemic steroids for nasal polyps up to Week 52 is presented. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis.
Change From Baseline in the Composite VAS Score (Combining VAS Scores for Nasal Obstruction, Nasal Discharge, Mucus in the Throat and Loss of Smell) During the 4 Weeks Prior to Week 52Baseline and Weeks 49 to 52Participants rated individual (nasal obstruction, nasal discharge, mucus in the throat, loss of smell, facial pain) and overall symptoms on a visual analog scale using an eDiary. Captured scores ranged between 0 (none) and 100 (as bad as you can imagine), final scores derived from electronically captured scores by dividing by 10. The composite VAS score was calculated as average of individual scores of nasal obstruction, nasal discharge, mucus in the throat and loss of smell and ranged between 0 and 10, with higher scores indicating greater disease severity. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. The average of daily scores in 4-weekly intervals were calculated and data is presented for Weeks 49-52. Baseline was defined as the average score from the 7 days of eDiary data collected prior to Day 1. Change from Baseline = Post-baseline value minus Baseline value.
Change From Baseline in Individual VAS Symptom Score: Loss of Smell During the 4 Weeks Prior to Week 52Baseline and Weeks 49 to 52Participants rated individual (nasal obstruction, nasal discharge, mucus in the throat, loss of smell, facial pain) and overall symptoms on a visual analog scale using an eDiary. Captured scores ranged between 0 (none) and 100 (as bad as you can imagine), final scores derived from the electronically captured scores by dividing by 10. The final loss of smell VAS score ranged between 0 and 10, with higher scores indicating greater disease severity. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. The average of daily scores in 4-weekly intervals were calculated and data is presented for Weeks 49-52. Baseline was defined as the average score from the 7 days of eDiary data collected prior to Day 1. Change from Baseline = Post-baseline value minus Baseline value.

Contacts

STUDY_DIRECTORGSK Clinical Trials

GlaxoSmithKline

Participant flow

Recruitment details

Participants (par.) were enrolled across 11 countries (Germany, Netherlands, Romania, Sweden, United Kingdom, United States, Argentina, Australia, Canada, Republic of Korea and Russian Federation).

Pre-assignment details

A total of 414 participants were enrolled and randomized in the study, of which only 407 participants received study treatment and were included in the Intent-to-Treat Population (defined as all randomized participants who took at least 1 dose of study treatment). Seven participants did not receive study treatment as they were randomized in error.

Participants by arm

ArmCount
Placebo
Participants were randomized to receive up to 13 subcutaneous (SC) doses of mepolizumab matching placebo every 4 weeks to Week 52 (Wk 52) on top of standard of care (SoC) for nasal polyps (NP) which included daily mometasone furorate nasal spray. By design, some randomized participants were eligible to enter a further 6-month no-treatment follow-up period to assess maintenance of response after cessation of treatment.
201
Mepolizumab 100 mg SC
Participants were randomized to receive up to 13 SC doses of mepolizumab 100 milligrams per milliliter (mg/mL) every 4 weeks to Week 52 on top of SoC for nasal polyps which included daily mometasone furorate nasal spray. By design, some randomized participants were eligible to enter a further 6-month no-treatment follow-up period to assess maintenance of response after cessation of treatment.
206
Total407

Baseline characteristics

CharacteristicPlaceboMepolizumab 100 mg SCTotal
Age, Continuous48.9 Years
STANDARD_DEVIATION 12.46
48.6 Years
STANDARD_DEVIATION 13.55
48.8 Years
STANDARD_DEVIATION 13.01
Race/Ethnicity, Customized
Race
AA/African H. and American Indian or Alaska Native
1 Participants0 Participants1 Participants
Race/Ethnicity, Customized
Race
Asian-Central/South Asian Heritage (H.)
1 Participants2 Participants3 Participants
Race/Ethnicity, Customized
Race
Asian-Japanese H./East Asian H./SouthEast Asian H.
8 Participants7 Participants15 Participants
Race/Ethnicity, Customized
Race
Black or African American (AA)
4 Participants5 Participants9 Participants
Race/Ethnicity, Customized
Race
White
187 Participants192 Participants379 Participants
Sex: Female, Male
Female
76 Participants67 Participants143 Participants
Sex: Female, Male
Male
125 Participants139 Participants264 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
0 / 2010 / 2061 / 650 / 69
other
Total, other adverse events
141 / 201139 / 20613 / 6514 / 69
serious
Total, serious adverse events
14 / 20112 / 2064 / 652 / 69

Outcome results

Primary

Change From Baseline in Nasal Obstruction Visual Analog Scale (VAS) Score During the 4 Weeks Prior to Week 52

Participants rated individual (nasal obstruction, nasal discharge, mucus in the throat, loss of smell, facial pain) and overall symptoms on a visual analog scale (VAS) using an electronic diary (eDiary). Captured scores ranged between 0 (none) and 100 (as bad as you can imagine), final scores derived from the electronically captured scores by dividing by 10. The final nasal obstruction VAS score ranged between 0 and 10, with higher scores indicating greater disease severity. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. The average of daily scores in 4-weekly intervals were calculated and data is presented for Weeks 49-52. Baseline was defined as the average score from the 7 days of eDiary data collected prior to Day 1. Change from Baseline = Post-baseline value minus Baseline value.

Time frame: Baseline and Weeks 49 to 52

Population: ITT Population

ArmMeasureValue (MEDIAN)
PlaceboChange From Baseline in Nasal Obstruction Visual Analog Scale (VAS) Score During the 4 Weeks Prior to Week 52-0.82 Scores on a scale
Mepolizumab 100 mg SCChange From Baseline in Nasal Obstruction Visual Analog Scale (VAS) Score During the 4 Weeks Prior to Week 52-4.41 Scores on a scale
p-value: <0.00195% CI: [-4.09, -2.18]Wilcoxon rank-sum test
Primary

Change From Baseline in Total Endoscopic Nasal Polyps Score at Week 52

Independent reviewers, blinded to treatment, reviewed image recordings of nasal endoscopies to determine total endoscopic NP score based on NP size. The right and left nostrils were scored from 0 to 4 (0 = No polyps; 1 = Small polyps in the middle meatus not reaching below the inferior border of the middle concha; 2 = Polyps reaching below the lower border of the middle turbinate; 3 = Large polyps reaching the lower border of the inferior turbinate or polyps medial to the middle concha; and 4 = Large polyps causing complete obstruction/congestion of the inferior meatus). The total score is the sum of the right and left nostril scores and ranges from 0 to 8, higher scores indicate greater disease severity. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. Baseline was defined as Day 1 value. Change from Baseline = Post-baseline value minus Baseline value.

Time frame: Baseline (Day 1) and Week 52

Population: ITT Population which included all randomized participants who took at least 1 dose of study treatment.

ArmMeasureValue (MEDIAN)
PlaceboChange From Baseline in Total Endoscopic Nasal Polyps Score at Week 520.0 Scores on a scale
Mepolizumab 100 mg SCChange From Baseline in Total Endoscopic Nasal Polyps Score at Week 52-1.0 Scores on a scale
p-value: <0.00195% CI: [-1.11, -0.34]Wilcoxon rank-sum test
Secondary

Change From Baseline in Individual VAS Symptom Score: Loss of Smell During the 4 Weeks Prior to Week 52

Participants rated individual (nasal obstruction, nasal discharge, mucus in the throat, loss of smell, facial pain) and overall symptoms on a visual analog scale using an eDiary. Captured scores ranged between 0 (none) and 100 (as bad as you can imagine), final scores derived from the electronically captured scores by dividing by 10. The final loss of smell VAS score ranged between 0 and 10, with higher scores indicating greater disease severity. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. The average of daily scores in 4-weekly intervals were calculated and data is presented for Weeks 49-52. Baseline was defined as the average score from the 7 days of eDiary data collected prior to Day 1. Change from Baseline = Post-baseline value minus Baseline value.

Time frame: Baseline and Weeks 49 to 52

Population: ITT Population

ArmMeasureValue (MEDIAN)
PlaceboChange From Baseline in Individual VAS Symptom Score: Loss of Smell During the 4 Weeks Prior to Week 520.00 Scores on a scale
Mepolizumab 100 mg SCChange From Baseline in Individual VAS Symptom Score: Loss of Smell During the 4 Weeks Prior to Week 52-0.53 Scores on a scale
p-value: 0.0295% CI: [-0.65, -0.08]Wilcoxon rank-sum test
Secondary

Change From Baseline in Overall VAS Score During the 4 Weeks Prior to Week 52

Participants rated individual (nasal obstruction, nasal discharge, mucus in the throat, loss of smell, facial pain) and overall symptoms on a visual analog scale using an eDiary. Captured scores ranged between 0 (none) and 100 (as bad as you can imagine), final scores derived from the electronically captured scores by dividing by 10. The final overall VAS score ranged between 0 and 10, with higher scores indicating greater disease severity. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. The average of daily scores in 4-weekly intervals were calculated and data is presented for Weeks 49-52. Baseline was defined as the average score from the 7 days of eDiary data collected prior to Day 1. Change from Baseline = Post-baseline value minus Baseline value.

Time frame: Baseline and Weeks 49 to 52

Population: ITT Population

ArmMeasureValue (MEDIAN)
PlaceboChange From Baseline in Overall VAS Score During the 4 Weeks Prior to Week 52-0.90 Scores on a scale
Mepolizumab 100 mg SCChange From Baseline in Overall VAS Score During the 4 Weeks Prior to Week 52-4.48 Scores on a scale
p-value: 0.00395% CI: [-4.1, -2.26]Wilcoxon rank-sum test
Secondary

Change From Baseline in Sino-nasal Outcome Test (SNOT)-22 Total Score at Week 52

The SNOT-22 is a 22-item self-reported questionnaire developed to measure symptoms and impacts related to chronic rhinosinusitis. The 22 questions are self-completed by participants based on their recall of their symptoms over the previous 2 weeks using a 6-point rating scale (0 = Not present/no problem; 1 = Very mild problem; 2 = Mild or slight problem; 3 = Moderate problem; 4 = Severe problem; 5 = Problem as bad as it can be). Scores for each question are summed to derive the total score. The SNOT-22 total score ranges from 0 to 110, with higher scores representing worse quality of life. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. Baseline was defined as Day 1 value. Change from Baseline = Post-baseline value minus Baseline value.

Time frame: Baseline (Day 1) and Week 52

Population: ITT Population. Only those participants with data available at the specified data point were analyzed.

ArmMeasureValue (MEDIAN)
PlaceboChange From Baseline in Sino-nasal Outcome Test (SNOT)-22 Total Score at Week 52-14.0 Scores on a scale
Mepolizumab 100 mg SCChange From Baseline in Sino-nasal Outcome Test (SNOT)-22 Total Score at Week 52-30.0 Scores on a scale
p-value: 0.00395% CI: [-23.57, -9.42]Wilcoxon rank-sum test
Secondary

Change From Baseline in the Composite VAS Score (Combining VAS Scores for Nasal Obstruction, Nasal Discharge, Mucus in the Throat and Loss of Smell) During the 4 Weeks Prior to Week 52

Participants rated individual (nasal obstruction, nasal discharge, mucus in the throat, loss of smell, facial pain) and overall symptoms on a visual analog scale using an eDiary. Captured scores ranged between 0 (none) and 100 (as bad as you can imagine), final scores derived from electronically captured scores by dividing by 10. The composite VAS score was calculated as average of individual scores of nasal obstruction, nasal discharge, mucus in the throat and loss of smell and ranged between 0 and 10, with higher scores indicating greater disease severity. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis. The average of daily scores in 4-weekly intervals were calculated and data is presented for Weeks 49-52. Baseline was defined as the average score from the 7 days of eDiary data collected prior to Day 1. Change from Baseline = Post-baseline value minus Baseline value.

Time frame: Baseline and Weeks 49 to 52

Population: ITT Population

ArmMeasureValue (MEDIAN)
PlaceboChange From Baseline in the Composite VAS Score (Combining VAS Scores for Nasal Obstruction, Nasal Discharge, Mucus in the Throat and Loss of Smell) During the 4 Weeks Prior to Week 52-0.89 Scores on a scale
Mepolizumab 100 mg SCChange From Baseline in the Composite VAS Score (Combining VAS Scores for Nasal Obstruction, Nasal Discharge, Mucus in the Throat and Loss of Smell) During the 4 Weeks Prior to Week 52-3.96 Scores on a scale
p-value: 0.0295% CI: [-3.44, -1.91]Wilcoxon rank-sum test
Secondary

Percentage of Participants Requiring at Least One Course of Systemic Steroids for Nasal Polyps up to Week 52

The number of courses of systemic steroids received by participants were recorded. For the purpose of this study, a course of systemic corticosteroid separated by less than 7 days was considered as a continuation of the same course. Percentage of participants requiring at least one course of systemic steroids for nasal polyps up to Week 52 is presented. Data up to Week 52, including from participants who remained in the study after early discontinuation from IP, were included in analysis.

Time frame: Up to Week 52

Population: ITT Population

ArmMeasureValue (NUMBER)
PlaceboPercentage of Participants Requiring at Least One Course of Systemic Steroids for Nasal Polyps up to Week 5237 Percentage of participants
Mepolizumab 100 mg SCPercentage of Participants Requiring at Least One Course of Systemic Steroids for Nasal Polyps up to Week 5225 Percentage of participants
p-value: 0.0295% CI: [0.36, 0.92]Regression, Logistic
Secondary

Percentage of Participants With Nasal Surgery Over Time

The percentage of participants with nasal surgery over time (by Weeks 8, 16, 24, 32, 40, 48 and 52) was derived from Kaplan-Meier time-to-event analyses for the event 'first nasal surgery'. Nasal surgery was defined as any procedure involving instruments resulting in incision and removal of tissue (polypectomy) in the nasal cavity. Time to first nasal surgery was defined as (Date of first nasal surgery - Date of first dose of study treatment) + 1. Percentage of participants with nasal surgery over time (by Weeks 8, 16, 24, 32, 40, 48 and 52) and corresponding 95% CI have been presented, calculated using the Kaplan-Meier method. Analysis included surgeries occurring up to Week 52, reported on-treatment and those reported after early discontinuation from IP by participants who remained in the study.

Time frame: Weeks 8, 16, 24, 32, 40, 48 and 52

Population: ITT Population

ArmMeasureGroupValue (NUMBER)
PlaceboPercentage of Participants With Nasal Surgery Over TimeWeek 4018.9 Percentage of participants
PlaceboPercentage of Participants With Nasal Surgery Over TimeWeek 81.0 Percentage of participants
PlaceboPercentage of Participants With Nasal Surgery Over TimeWeek 163.5 Percentage of participants
PlaceboPercentage of Participants With Nasal Surgery Over TimeWeek 249.1 Percentage of participants
PlaceboPercentage of Participants With Nasal Surgery Over TimeWeek 3214.2 Percentage of participants
PlaceboPercentage of Participants With Nasal Surgery Over TimeWeek 4822.0 Percentage of participants
PlaceboPercentage of Participants With Nasal Surgery Over TimeWeek 5223.6 Percentage of participants
Mepolizumab 100 mg SCPercentage of Participants With Nasal Surgery Over TimeWeek 489.2 Percentage of participants
Mepolizumab 100 mg SCPercentage of Participants With Nasal Surgery Over TimeWeek 326.0 Percentage of participants
Mepolizumab 100 mg SCPercentage of Participants With Nasal Surgery Over TimeWeek 80.5 Percentage of participants
Mepolizumab 100 mg SCPercentage of Participants With Nasal Surgery Over TimeWeek 407.6 Percentage of participants
Mepolizumab 100 mg SCPercentage of Participants With Nasal Surgery Over TimeWeek 161.0 Percentage of participants
Mepolizumab 100 mg SCPercentage of Participants With Nasal Surgery Over TimeWeek 529.2 Percentage of participants
Mepolizumab 100 mg SCPercentage of Participants With Nasal Surgery Over TimeWeek 244.0 Percentage of participants
p-value: 0.00395% CI: [0.25, 0.76]Cox Proportional Hazards Model

Source: ClinicalTrials.gov · Data processed: Jul 23, 2026