Real-world use affirms mepolizumab efficacy in chronic rhinosinusitis with nasal polyps

Mepolizumab proves beneficial to adults with chronic rhinosinusitis with nasal polyps treated in routine clinical practice, especially in terms of reducing oral corticosteroid (OCS) and surgical burden, according to a study. This supports clinical data from the pivotal phase III SYNAPSE study.

Analysis of retrospective data from the Komodo Research database, which encompasses >320 million patients in the US, showed that between the pre- and post-index initiation of mepolizumab, there was a significant reduction in nasal polyp-related OCS use, as measured in multiple different outcomes, reported Dr Juan Carlos Cardet of the University of South Florida Health Morsani College of Medicine in in Tampa, Florida, US.

In particular, total OCS dose dropped by about 64 percent per patient per year (PPPY), from 310 to 119 mg of prednisone PPPY (rate ratio, 0.36, 95 percent confidence interval [CI], 0.27–0.47; p<0.001), with the proportion of patients having at least 1 OCS prescription having decreased by 70 percent, from 59 percent to 18 percent (risk ratio, 0.30, 95 percent CI, 0.23–0.40; p<0.001). [AAAAI 2024, abstract 813]

Moreover, the rate of OCS burst (≥20 mg prednisone equivalents for 2‒28 days) decreased from 0.7 to 0.3 patient per year (PPY) between the pre- and post-index periods. This corresponded to a 63-percent decline (rate ratio, 0.37, 95 percent CI, 0.28–0.50; p<0.001), Cardet noted.

Findings for sinus surgeries were also significant.

Cardet reported that the rate of sinus surgeries fell by 77 percent, from 0.9 PPY in the pre-mepolizumab period to 0.2 PPY in the post-mepolizumab period (rate ratio, 0.23, 95 percent CI, 0.13–0.40; p<0.001). The number of patients who underwent a sinus surgical procedure (ie, polypectomy, sinusotomy, or functional endoscopic sinus surgery) at least once dropped by 72 percent, from 29 percent to 8 percent (risk ratio, 0.28, 95 percent CI, 0.17–0.44; p<0.001).

Claims for sinus CT scans also decreased from 0.6 to 0.2 PPY, which translated to a 74-percent reduction (rate ratio, 0.26, 95 percent CI, 0.19–0.36; p<0.001).

A sensitivity analysis that excluded patients with OCS prescription for fungal rhinosinusitis or cystic fibrosis did not significantly alter the results, with similar degree of reductions seen for total OCS dose (rate ratio, 0.33, 95 percent CI, 0.21–0.53), the proportion of patients with at least one OCS prescription (risk ratio, 0.27, 95 percent CI, 0.17–0.43; p<0.001), and the rate of sinus surgeries PPY (rate ratio, 0.31, 95 percent CI, 0.13–0.79; p=0.013).

“These are real-world findings that supplement the [pivotal] randomized controlled trial data and tell us a little bit more about how mepolizumab can reduce exposure to OCS and additional surgeries,” Cardet said.

In the phase III SYNAPSE study, mepolizumab was shown to improve sinosanal outcomes and reduce the need for systemic corticosteroids or surgery in patients with chronic rhinosinusitis with nasal polyps. These phase III data served as the basis for the US Food and Drug Administration (FDA) approval of the monoclonal antibody as an add-on maintenance treatment for chronic rhinosinusitis with nasal polyps in adults with inadequate response to nasal corticosteroids. [Lancet Respir Med 2021;9:1141-1153; https://tinyurl.com/2dm9r8fw]

Taken together, the clinical and real-world data indicate that mepolizumab is useful in the treatment of patients with chronic rhinosinusitis with nasal polyps, who are at increased risk of systemic corticosteroid-related adverse outcomes and have a health-related quality of life similar to patients with asthma, diabetes, or rheumatoid arthritis, Cardet said. [Allergy Asthma Proc 2019;40:48-56; J Asthma Allergy 2023;16:323-332; Clin Ther 2022;44:1187-1202]

The retrospective analysis included 240 adults (mean age 49.1 years, 55.0 percent female, 36.3 percent non-Hispanic White, with chronic rhinosinusitis with nasal polyps who had at least two mepolizumab dispensing/administrations within 6 months of index date (first dispensing or administration of the drug) and 12 months of continuous health plan enrolment in the pre-index period and at least 6 months in the post-index period.

At baseline, 79.2 percent were on antibiotics and 17.1 percent were on biologics (ie, dupilumab or omalizumab). None of the included patients used reslizumab, benralizumab, or tezepelumab at any point during the study period.