Intranasal corticosteroids used with antibiotics are known to improve rhinosinusitis symptoms compared with antibiotic therapy alone. However, the efficacy of intranasal corticosteroid monotherapy for acute, uncomplicated rhinosinusitis is not established.

To evaluate efficacy and safety of mometasone furoate nasal spray (MFNS) versus amoxicillin and placebo in patients with acute, uncomplicated rhinosinusitis.

In this double-blind, double-dummy trial, subjects (≥12 years; N = 981) were randomized to MFNS 200 μg once daily or twice daily for 15 days, amoxicillin 500 mg 3 times daily for 10 days, or respective placebo. Follow-up was 14 days. The primary efficacy endpoint was mean am/pm major symptom score over the treatment phase. Secondary efficacy endpoints included total symptom score. Safety assessments included disease recurrence during follow-up and adverse event monitoring.

Mometasone furoate nasal spray 200 μg twice daily was significantly superior to placebo (P < .001) and amoxicillin (P = .002) at improving major symptom score. Starting on day 2, MFNS 200 μg twice daily improved total symptom score throughout treatment versus amoxicillin (P = .012) and placebo (P < .001). Global response to treatment was significantly greater with MFNS 200 μg twice daily versus amoxicillin (P = .013) and placebo (P = .001). Although significantly superior to placebo, MFNS 200 μg once daily was not superior to amoxicillin for the primary or secondary efficacy endpoints. All treatments were well tolerated with a similar incidence of adverse events.

In patients with acute, uncomplicated rhinosinusitis, MFNS 200 μg twice daily produced significant symptom improvements versus amoxicillin and placebo, without predisposing the patient to disease recurrence or bacterial infection.