Allergen injection therapy with glutaraldehyde-modified--ragweed pollen-tyrosine adsorbate. A double-blind trial.

The effect of a preseasonal course of four injections of glutaraldehyde-modified—ragweed pollen-tyrosine adsorbate (MRTA), in a total dose of 7,000 Noon pollen units, was compared with a tyrosine base placebo in a double-blind trial in 43 matched patients with ragweed pollen-induced allergic rhinitis. During the pollen season, troublesome symptoms were treated with a standardized therapeutic regimen. The minimum medication requirement that adequately controlled symptoms was used as the main indicator of severity of the allergic rhinitis. Consequently, the symptom scores were similar in both treatment groups; however, the MRTA-treated group required approximately 50% less medication than the placebo group (p < 0.05). Subjective improvement was reported by 67% of the MRTA group and 38% of the placebo group (0.05 < p < 0.1). Serum concentrations of IgE and IgG antibodies to ragweed increased in response to MRTA (p < 0.02) but not in response to placebo. Side effects of MRTA included generalized urticaria in 2, mild asthma in 1, and large late swellings at the injection site which necessitated stopping the injections in 6 patients. MRTA was superior to placebo in reducing the severity of ragweed pollen-induced allergic rhinitis and was associated with a modest incidence of side effects.