Once versus twice daily dosing of terfenadine in the treatment of seasonal allergic rhinitis: US and European studies.
Terfenadine was compared for efficacy in treatment regimens of 120 mg once daily (qd) and 60 mg twice daily (bid) in patients with seasonal allergic rhinitis in double blind, randomized, parallel 1-week studies, three in Europe (one multicenter study, three sites; n = 191) and one in the US (single center; n = 201). Patients had moderate or severe symptoms for 2 or more years and positive skin tests to relevant pollen antigens. On entry and final visit individual symptoms were rated by physicians on a visual analog scale in Europe and a numerical scale in the US. Most patients filled out daily symptom diaries during the studies. Individual symptom scores and total symptom scores, (calculated by adding individual symptom scores together) as assessed by physicians and patients, were similar at baseline for both treatment regimens on entry, with improvement during the week. There were more patients with complete and marked relief in Europe than in the US. (Total symptom scores as assessed by physicians, for instance, improved from baseline ratings of 407 for the 60 bid regimen and 431 for the 120 qd regimen in Europe to 102 and 95 at final visit, and in the US from 8.8 for 60 bid and 8.5 for the 120 qd to 4.5 and 4.1). There was no statistical difference between the two treatment regimens in Europe or the US. Terfenadine, 120 mg once daily, is as effective as the currently approved dosage of 60 mg twice daily in the treatment of seasonal allergic rhinitis, and terfenadine, 120 mg once daily, has the added convenience of allowing the patient once a day dosing.
Chu
T J
TJ
Allergy & Asthma Associates of Santa Clara Valley, Med Corp, San Jose, CA 95117.
Yamate
M
M
Biedermann
A A
AA
Wolfe
J D
JD
Goldsobel
A B
AB
D000293:Adolescent; D000328:Adult; D000368:Aged; D001559:Benzhydryl Compounds / Q000009:adverse effects / Q000592:standards / Q000627:therapeutic use*; D002648:Child; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005060:Europe; D005260:Female; D006634:Histamine H1 Antagonists / Q000009:adverse effects / Q000592:standards / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic; D006255:Rhinitis, Allergic, Seasonal / Q000188:drug therapy* / Q000453:epidemiology; D016593:Terfenadine; D014481:United States
D001559:Benzhydryl Compounds; D006634:Histamine H1 Antagonists; D016593:Terfenadine