Peak nasal inspiratory flow assessment of polyp size and response from SYNAPSE

In the phase III SYNAPSE study, mepolizumab plus standard of care reduced total endoscopic nasal polyp score (NPS) versus that with placebo in patients with chronic rhinosinusitis with nasal polyps.

Our aim was to investigate relationships between NPS and (1) peak nasal inspiratory flow (PNIF) and (2) patient-reported outcomes.

In this post hoc analysis, patients randomized 1:1 received mepolizumab, 100 mg, or placebo subcutaneously every 4 weeks (plus standard of care). Changes from baseline in PNIF (week 52), visual analog scale scores (overall symptoms, nasal obstruction, and loss of smell [weeks 49-52]), and total 22-Item Sino-Nasal Outcome Test score (week 52) were assessed in patients with or without improvements in NPS (improvement of ≥1 point) or without (improvement of <1 point or worsening).

Patients with improvements in NPS had greater improvements in PNIF (a median of 50 L per minute [interquartile range (IQR) = 10.5-87.5] with mepolizumab vs a median of 40 L per minute [IQR = 0-85.0] with placebo) than did those patients without improvements in NPS (a median of 0.0 L per minute [IQR = -10.0 to 45.0] with mepolizumab vs a median of 0.0 L per minute [IQR = -30.0 to 30.0] with placebo). Similar results were seen for the following: change from baseline in overall symptoms (a median of -5.8 [IQR = -8.1 to -3.80] with mepolizumab and a median of -4.1 [IQR = -7.0 to -1.2] with placebo with improvement in NPS vs a median of -1.3 [IQR = -6.3 to 0.0] with mepolizumab and a median of -0.1 [IQR = -3.4 to 0.0] with placebo without improvement in NPS); change in nasal obstruction (a median of -5.7 [IQR = -8.2 to -3.5] with mepolizumab and a median of -4.5 [IQR = -7.3 to -1.2] with placebo with improvement in NPS vs a median of -1.3 [IQR = -6.6 to 0.0] with mepolizumab and a median of 0.0 [IQR = -3.6 to 0.0] with placebo without improvement in NPS); change in loss of smell (a median of -2.8 [IQR = -7.9 to 0.0] with mepolizumab and a median of -0.7 [IQR = -4.0 to 0.0] with placebo with improvement in NPS vs a median of 0.0 [IQR = -2.4 to 0.0] with mepolizumab and a median of 0.0 [IQR = -0.3 to 0.0]) with placebo without improvement in NPS); and change in visual analog scale score and 22-Item Sino-Nasal Outcome Test total score (a median of -37.0 [IQR = -52.0 to -24.0] with mepolizumab and a median of -29.0 [IQR = -43.0 to -9.0] with placebo with improvement in NPS vs a median of -16.0 [IQR = -42.0 to 0.0] with mepolizumab and a median of 0.0 [IQR = -27.0 to 0.0] with placebo without improvement in NPS).

Improvement in NPS was associated with improvements in PNIF and patient-reported outcomes irrespective of treatment. PNIF could be a useful noninvasive tool for monitoring nasal polyp size.