The bronchosparing effect of celiprolol, a new beta 1- alpha 2-receptor antagonist on pulmonary function of propranolol-sensitive asthmatics.

Twelve normotensive asthmatics who demonstrated bronchoconstriction after a single oral dose of 80 mg of propranolol received (according to a double-blind, randomized, crossover design) placebo, celiprolol 200 mg, and celiprolol 400 mg at intervals of at least three days. Pulmonary function parameters were measured by whole body plethysmography just before treatment and hourly for three hours. Thereafter, terbutaline (0.5 mg), a beta2 agonist, was administered in aerosol form at 15-minute intervals for a total of five doses. This design permitted a safety assessment of the effect of placebo and celiprolol on resting pulmonary function and the evaluation of any interaction between this beta blocker and terbutaline. Propranolol 80 mg produced a statistically significant decrease in a forced one second expiratory volume and forced vital capacity, and a pronounced rise in airways resistance as compared with either dose of celiprolol or with placebo (P less than .001). The effect of celiprolol was not statistically distinguishable from placebo. Terbutaline caused further net bronchodilation after administration of celiprolol and placebo but, even at supratherapeutic doses, failed to restore pulmonary function parameters to baseline levels after treatment with propranolol. The bronchosparing effect of celiprolol may be due to its unique pharmacologic profile, which includes cardioselectivity, modest beta 2-agonist activity, and alpha 2-receptor blockade.