title: 24-hour efficacy of once-daily desloratadine therapy in patients with seasonal allergic rhinitis [ISRCTN32042139].
abstract: BACKGROUND
  Early studies with desloratadine demonstrated efficacy in treating seasonal allergic rhinitis (SAR). A dose-ranging study was conducted to characterize its 24-hour efficacy in patients with SAR.
  
  
  METHODS
  Patients (N = 1,026) were randomly assigned once-daily (QD) desloratadine (2.5, 5, 7.5, 10, or 20 mg) for 2 weeks in a placebo-controlled, double-blind study. The end point of 24-hour efficacy was assessed by the mean change from baseline in the average AM instantaneous total symptom score (TSS) over the treatment period. Day 2 data were assessed for efficacy of desloratadine following the first dose. Other efficacy variables included AM/PM previous total nasal and nonnasal symptom scores and individual symptom scores.
  
  
  RESULTS
  Desloratadine 5-20 mg was significantly (P <.01) more effective than placebo in improving total AM instantaneous TSS and AM/PM previous total nasal and nonnasal symptom scores. This dosing range also was significantly (P <.01) more effective than placebo for reducing AM instantaneous TSS beginning with the first dose; thus, demonstrating the full 24-hour efficacy of desloratadine. AM/PM previous scores for all individual symptoms, including nasal congestion, were also significantly improved versus placebo (P <.05) with desloratadine at 5, 7.5, and 20 mg. All treatments were well tolerated. There were no clinically meaningful changes in electrocardiogram parameters.
  
  
  CONCLUSIONS
  Desloratadine 5-20 mg provided significant 24-hour relief of SAR signs and symptoms. There were no statistically significant differences between the 4 largest doses suggesting that desloratadine 5 mg QD offers the best therapeutic profile for patients with SAR.
authors.affiliation: Schering-Plough Research Institute, Kenilworth, New Jersey, USA. luis.salmun@spcorp.com
authors.forename: Luis M
authors.initials: LM
authors.lastname: Salmun
authors.forename: Richard
authors.initials: R
authors.lastname: Lorber
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002648:Child; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D039563:Histamine H1 Antagonists, Non-Sedating / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D017336:Loratadine / Q000008:administration & dosage* / Q000009:adverse effects / Q000031:analogs & derivatives*; D008297:Male; D008875:Middle Aged; D006255:Rhinitis, Allergic, Seasonal / Q000188:drug therapy*
chemical_list: D039563:Histamine H1 Antagonists, Non-Sedating; D017336:Loratadine; C121345:desloratadine