Suplatast tosilate affects the initial increase in specific IgE and interleukin-4 during immunotherapy for perennial allergic rhinitis

Suplatast tosilate can inhibit IL-4 production and suppress IgE synthesis i n vitro. However? the theory that the agent causes changes in production of IL-4 and IgE in vivo has little experimental support. Immunotherapy could decrease the specific IpE response, but such a favourable effect is only po ssible with prolonged therapy after an initial increase in specific IE. The use of suplatast tosilate together with immunotherapy may blunt the initia l rise in specific IgE and decrease serum levels of specific IgE more quick ly. Eighty-three adult patients with perennial allergic rhinitis due to Der matophagoides farinae (D. farinae) were treated for 6 months with one of 3 treatments. Seventeen patients were treated with oral administration of 300 mg/day suplatast tosilate alone. Forty-six patients were treated with immu notherapy using standardized D. farinae alone. Twenty patients were treated with immunotherapy together with concurrent oral administration of 300 mg/ day suplatast tosilate. Serum samples were collected 3 times from each pati ent, at enrolment, at 3 months and at 6 months after enrolment. Oral admini stration of suplatast tosilate for 3 and 6 months significantly decreased s erum levels of IL-4 and specific IgE, and the rate of decrease in specific IgE correlated significantly with the rate of decrease in IL-4. The rates o f decrease in IL-4 and specific IgE at 3 and 6 months were significantly gr eater in the patients treated with suplatast tosilate and immunotherapy tha n in those treated with immunotherapy alone. In conclusion, suplatast tosil ate is able significantly to decrease serum levels of IL-4 and specific IgE , and the use of the drug together with immunotherapy can blunt the initial increase in specific IgE during the first 6 months of immunotherapy.