Evaluation of the Bronchodilating and Antiallergic Properties of a Beta-Adrenoceptor Stimulant, KWD 2131, in Asthmatic Patients*

KWD 2131 (1-(3,5-dihydroxyphenyl)-(1,1dimethyl-2-hydroxyethyl-amino/ethanol sulphate) is a β-adrenoceptor stimulating compound that has been shown to be equipotent to terbutaline with regard to inhibition of anaphylactic histamine release from guinea pig lung tissue but less potent than terbutaline as a cardioaccelerator in this species. In the present study KWD 2131 was found to be about 5–10 times less potent than terbutaline as a cardioaccelerator, tremorogenic and bronchodilator agent on subcutaneous (s.c.) injection in man. S.c. injection of KWD 2131 in a subthreshold dose for bronchodilatation, i.e. 0.3 mg or 0.6 mg, given prior to a bronchial provocation test with specific allergen had no protective effect on the changes in specific airway conductance and peak expiratory flow in a double-blind cross-over study in 12 patients with allergic asthma. It is concluded that KWD 2131 probably has a less selective antiallergic activity in man as compared to guinea pig and that the methodology employed for the evaluation is useful for the characterization of antiallergic drugs with bronchodilator properties.