Efficacy of desloratadine in intermittent allergic rhinitis: a GA(2)LEN study

The Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines proposed a classification for allergic rhinitis based on the duration of symptoms (intermittent, persistent) rather than on the time of allergen exposure (seasonal, perennial). There is no placebo-controlled, randomized clinical trial on intermittent allergic rhinitis (IAR) to date. Desloratadine (DL) is recommended for the first-line treatment of seasonal and perennial allergic rhinitis.

To assess the efficacy and safety of DL in subjects with IAR based on the ARIA classification.

Patients over 12 years of age with IAR were assessed over 15 days of treatment with DL 5 mg once daily (n = 276) or placebo (n = 271). The primary endpoint was the AM/PM reflective total 5 symptom score (T5SS). Secondary endpoints included AM/PM instantaneous T5SS and individual symptoms, therapeutic response, symptom severity by visual analogue scale, and quality-of-life.

The mean reduction of AM/PM reflective T5SS was significantly greater with DL than with placebo over 15 days (-3.01 vs-2.13, P < 0.001) and on each individual day (P < 0.05). Mean AM instantaneous T5SS was reduced significantly with DL compared to placebo as early as day 2 (-1.84 vs-0.89; P < 0.001). The therapeutic response and improvement in quality-of-life were significantly greater with DL than with placebo (P < 0.001 for each). The frequency of treatment-related adverse events was low and similar between DL (7.2%) and placebo (7.0%).

This is the first large trial to show that treatment can be effective in IAR. Desloratadine was effective and safe.