Clinical effects of HC 20-511 (ketotifen) in bronchial asthma and its inhibitory effect on antigen-induced morphological changes of basophils

Sixty-four patients with confirmed bronchial asthma were treated with HC 20-511 (Ketotifen). HC20-511 was evaluated to be very effective in 6.3%, effective in 50.0% and slightly effective in 10.9% of these patients. The appearance of reactive basophils was inhibited by HC 20-511 in 5 out of 6 cases of reaction to house dust, in all three cases with buckwheat allergy to their allergen and in 7 out of 11 cases to anti-IgE. These results confirm that HC 20-511 inhibits type I allergic reactions induced by specific allergen and IgE.