Long-term multicentric study with azelastine in patients with intrinsic asthma.

Efficacy and tolerance of azelastine (A 5610; CAS 58581-89-8), a new antiallergic compound with a unique structure, were investigated over up to one year of treatment in 225 male and female out-patients (age mean +/- s = 48 +/- 13 years) suffering from chronified intrinsic asthma. The trial was conducted by 24 German and Austrian consulting physicians of pneumology. Plasma levels indicated sufficient compliance in almost 90% of the patients. Tablets containing 4.4 mg azelastine HCl were administered b.i.d. in addition to the pre-existing antiasthmatic medication. Only other antiallergic agents were excluded. Adverse events, vital parameters and laboratory tests on safety were tightly assessed. Eighteen patients dropped out because of adverse events, 78 reported adverse experiences under therapy, normally mild and "vegetative" symptoms. No indicative findings regarding blood pressure, heart rate and laboratory tests were seen. The most frequent observations were taste disorders, asthenia and weight gain. No serious side effects at all were reported. The results on efficacy obtained from this non-controlled study may be predicative due to a baseline validation by an initial single blind placebo controlled run-in phase. Statistically significant improvements were seen for FEV1 and for the physicians' and the patients' rating on efficacy. To a lesser extent peak flow and airway resistance were improved, too. Thus, azelastine was safely tolerated over one year and might be effective in intrinsic asthma.