zaprinast and Asthma--Exercise-Induced

We conducted a placebo controlled, double-blind trial on the effect of a single dose of zaprinast (M&B 22,948, an orally active mast cell stabilizer) on exercise-induced asthma in 15 children. We demonstrated no prophylactic effect on the whole group. A trend towards effectiveness was shown when the results for children whose asthma was not steroid dependent were analysed alone.

Topics: Adolescent; Asthma; Asthma, Exercise-Induced; Child; Clinical Trials as Topic; Double-Blind Method; Humans; Purinones

M&B 22,948 (2-o-propoxyphenyl-8-azapurin-6-one) is an orally absorbed mast cell stabilizer which is 30 times as potent as disodium cromoglycate in laboratory and animal studies. In a double-blind placebo-controlled cross-over trial we studied the protection afforded by a single oral dose of 10 mg of M&B 22,948 against asthma induced by histamine and exercise, each in 12 patients. Compared with placebo the drug had no significant effect on the response to inhaled histamine but significantly inhibited the fall in FEV1 induced by exercise on treadmill (P less than 0.005). The exercise-induced fall in FEV1 was less following M&B 22,948 than placebo in all patients and the fall was inhibited by more than 50% in five (42%) of 12 patients. The degree of inhibition was significantly correlated with the plasma drug concentration (r = 0.65, P less than 0.025). M&B 22,948 merits evaluation in the treatment of asthma.

Topics: Adolescent; Adult; Asthma; Asthma, Exercise-Induced; Bronchial Provocation Tests; Clinical Trials as Topic; Double-Blind Method; Female; Forced Expiratory Volume; Humans; Male; Middle Aged; Physical Exertion; Purinones