Allergic rhinitis is a very common medical problem affecting adults and children alike. It has been estimated that 20% to 25% of the world's population suffer from allergic rhinitis, resulting in considerable morbidity - impaired quality of life. In the U.S., there is an estimated $2.4 billion annual medical cost associated with allergic rhinitis.~In Taiwan, household dust mites (HDM) are primary allergens causing allergic reactions including allergic rhinitis. The incidence of HDM in Taiwan can be as high as 100%. Df, Dp and Blomia tropicalis (Bt) rank among the top 3 most common household dust mites. Antihistamines remain a major therapy for treatment of allergic rhinitis. Chinese herbs have long been used to treat different allergic and immunologic diseases. YU-PING-FENG-SAN (YPFS) with a formulation that contains 3 herbs [Huangqi (HQ), baizhu (BZ), and fangfeng (FF)] has been reported as one of the effective traditional Chinese medicines for the treatment of recurrent rhinitis.~In 3 previous non-placebo controlled clinical studies in perennial rhinitis, it has been demonstrated that by adding Xingyi(XY) to a YPFS formula with CQ, BZ, and FF, additional efficacy benefits can be obtained.~The aim of this double-blind, randomized, parallel group, placebo-controlled study is to assess the efficacy and safety of EWO1 in patients with moderate to severe perennial allergic rhinitis. After a 2-week placebo run-in period, patients who satisfy all of the inclusion/exclusion criteria will be randomized 1:1 to receive either EWO1, or placebo for 28 days. After the treatment-period, patients will be followed for 14 days to see if there is any rebound in rhinitis symptoms. The Primary efficacy endpoint is weekly combined symptom scores at the end of treatment. Besides, intent to treat analyses will be carried out for both efficacy and safety. A minimum of 60 patients will be randomized into this two-treatment parallel-design study.
The aim of this double-blind, randomized, parallel group, placebo-controlled study is to assess the efficacy and safety of EWO1 in patients with moderate to severe perennial allergic rhinitis (AR).