Mepolizumab (Nucala), an IL-5 antibody was approved in the past for patients who have severe persistent asthma.
A recent study sought to determine whether mepolizumab could reduce the need for surgery in patients with severe recurrent bilateral nasal polyps. Chronic sinusitis is common, and it can be categorized into 2 types: with nasal polyps and without nasal polyps. Up to 4% of the population is estimated to be affected by nasal polyps. Nasal polyps have a negative effect on quality of life including physical health, general health, social functioning, sleep and mental health and it often leads to missed work. Symptoms experienced by patients with nasal polyps include nasal blockage, loss of smell, runny nose and asthma related issues.
Current treatment options for patients with nasal polyps are limited to intranasal corticosteroids (i.e. Nasonex), oral corticosteroids (prednisone), long-term antibiotics, and surgery. Nasal steroids are usually the initial treatment option for patients with mild disease. Short term courses of oral steroids are reserved for more severe cases.
Although symptoms can be controlled medically in some patients, surgery is often required. Surgery can range from a single polyp removal to full removal of polyp issue from sinuses. The recurrence rate is high for patients and repeated surgery is often required, one study shoed that 15% of patients had 4-6 procedures within an 8 year period. Even after surgery nasal steroids is still required. There is a proportion of patients whom surgery and oral steroids both fail to achieve disease control.
IL-5 is the critical factor that promotes eosinophils and survival. Mepolizumab, an IL-5 antibody is under investigation for the treatment of nasal polyps. Mepolizumab reduces blood and tissue eosinophil counts and is approved for the treatment of severe eosinophilic asthma. Both severe eosinophilic asthma and nasal polyps have local eosinophilic inflammation. IL-5 seems to play a key role in the development of nasal polyps. An aim of a recent study published in Journal of Allergy and Clinical Immunology, was to build on previous studies and determine whether mepolizumab (Nucala) could reduce the need for surgery in patients with severe recurrent bilateral nasal polyps.
107 patients (half received mepoliuzmab and half placebo) with severe recurrent polyps that required surgery, demonstrated mepolizumab treatment
- reduced the need for surgery compared to placebo
- improved nasal polyp symptoms (runny nose, mucus in throat, nasal blockage, sense of smell) compared to placebo
- demonstrated a safety profile compared to placebo
Efficacy results from this study were consistent with a smaller study investigating mepolizumab in the treatment of nasal polyps. There was a similar study using dupilumab (an anti-IL 4/13 therapy) that also showed improved nasal polyp scores. Currently dupilumab is approved for atopic dermatitis, but it is seeking other indications as well.
Side effects seen in this study for mepolizumab (> 5%) were, headache, nasopharyngitis, oropharyngeal pain and back pain. Limitations of this study were that patients were only studied for 6 months, there were low patient numbers involved and the dose given was 750mg IV every 4 weeks. Currently the dose approved for Nucala (mepolizumab) is 100mg subcutaneously every 4 weeks for add-on maintenance treatment of adults with severe eosinophilic asthma, which will be used for future studies. Not every patient with nasal polyps responded to mepolizumab, additional future research will be needed to identify which patients would most likely benefit to mepolizumab treatment. Perhaps specific biomarkers could be identified.
Of note, the patients in this study were not identified with having Samter’s Triad (nasal polyps, asthma, aspirin sensitivity), the management and treatment of these patients could be different.
In conclusion, mepolizumab reduced the numbers of patients needing surgery for nasal polyps and improved their nasal polyps overall. If you suffer from recurrent nasal polyps, have your ENT (Ear, Nose and Throat) doctor coordinate care with your allergy doctor about what the best treatment option is for you.
Update July 29, 2021
FDA has approved Nucala for Nasal Polyps. It is for the add on maintenance treatment for chronic rhinosinusitis with nasal polyps for adults 18 years and older with inadequate response to nasal steroids.