A comparison of oral procaterol and albuterol in reversible airflow obstruction

The efficacy and safety of orally administered procaterol hydrochloride, a potent beta 2-adrenergic bronchodilator, was compared with that of albuterol in an eight-center, double-blind study conducted in 223 patients with mild to moderate, reversible bronchial airway obstruction. After a 1-wk placebo washout period, patients were administered either procaterol 0.05 mg twice daily for 2 wk followed by 0.10 mg twice daily for 10 wk or albuterol 2 mg three times a day for 2 wk followed by 4 mg three times a day for 10 wk. Spirometry determinations 1.5 h postdose showed consistently greater percent improvements from predose in FVC, FEV1, and FEF25-75 with procaterol than with albuterol at Weeks 1, 2, 4, 8, and 12. Treatment differences were statistically significant (alpha = 0.05) after 2 wk, 2 months, and 3 months of treatment. Bronchodilatation was evident 0.5 h after dosing and peaked at 1.5 to 3 h postdose for both treatments. The duration of action (i.e., time until spirometry determinations were lower than those at 0.5 h postdose) was at least 5 h after procaterol but only 3 h after albuterol. There was no evidence of tolerance with continued procaterol treatment, whereas a diminished duration of response to albuterol was observed with long-term treatment. Tremor was reported statistically more frequently in patients receiving procaterol than in those receiving albuterol (alpha = 0.05); the frequencies of other adverse events were similar for the two groups. No statistically significant treatment differences were noted for asthma symptoms, global evaluations, ECG results, vital signs, or clinical laboratory measurements.(ABSTRACT TRUNCATED AT 250 WORDS)