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Xyzal

Clinical Pharmacology
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Clinical Pharmacology

The efficacy of XYZAL was evaluated in six randomized, placebo-controlled, double-blind clinical trials in adult and adolescent patients 12 years and older with symptoms of seasonal allergic rhinitis or perennial allergic rhinitis. The six clinical trials include three dose-ranging trials of 2 to 4 weeks duration, one 2-week efficacy trial in patients with seasonal allergic rhinitis, and two efficacy trials (one 6-week and one 6- month) in patients with perennial allergic rhinitis.

These trials included a total of 2412 patients (1068 males and 1344 females) of whom 265 were adolescents 12-17 years of age. Efficacy was assessed using a total symptom score from patient recording of 4 symptoms (sneezing, rhinorrhea, nasal pruritus, and ocular pruritus) in five studies and 5 symptoms (sneezing, rhinorrhea, nasal pruritus, ocular pruritus, and nasal congestion) in one study. Patients recorded symptoms using a 0-3 categorical severity scale (0 = absent, 1 = mild, 2 = moderate, 3 = severe) once daily in the evening reflective of the 24 hour treatment period. In one study, patients also recorded these symptoms in an instantaneous (1 hour before the next dose) manner. The primary endpoint was the mean total symptom score averaged over the first week and over 2 weeks for seasonal allergic rhinitis trials, and 4 weeks for perennial allergic rhinitis trials.

The three dose-ranging trials were conducted to evaluate the efficacy of XYZAL 2.5, 5, and 10 mg once daily in the evening. One trial was 2 weeks in duration conducted in patients with seasonal allergic rhinitis, and two trials were 4 weeks in duration conducted in patients with perennial allergic rhinitis. In these trials, each of the three doses of XYZAL demonstrated greater decrease in the reflective total symptom score than placebo and the difference was statistically significant for all three doses in two of the studies. Results for two of these trials are shown in Table 3.

Table 3 : Mean Reflective Total Symptom Score in Allergic Rhinitis Dose-Ranging Trials

Treatment N Baseline On
Treatment
Adjusted
Mean
Difference from Placebo
Estimate 95% CI p-value
Seasonal Allergic Rhinitis Trial — Reflective total symptom score
XYZAL 2.5 mg 116 7.83 4.27 0.91 (0.37, 1.45) 0.001
XYZAL 5 mg 115 7.45 4.06 1.11 (0.57, 1.65) <0.001
XYZAL 10 mg 118 7.15 3.57 1.61 (1.07,2.15) <0.001
Placebo 118 7.94 5.17      
Perennial Allergic Rhinitis Trial — Reflective total symptom score
XYZAL 2.5 mg 133 7.14 4.12 1.17 (0.71, 1.63) <0.001
XYZAL 5 mg 127 7.18 4.07 1.22 (0.76, 1.69) <0.001
XYZAL 10 mg 129 7.58 4.19 1.10 (0.64, 1.57) <0.001
Placebo 128 7.22 5.29      
*Total symptom score is the sum of individual symptoms of sneezing, rhinorrhea, nasal pruritus, and ocular pruritus as assessed by patients on a 0-3 categorical severity scale.

Brand Name: Xyzal
Generic Name: Levocetirizine Dihydrochloride
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