Treatment of reversible chronic airways obstruction with doxofylline compared with slow-release theophylline: a double-blind, randomized, multicentre trial

Abstract

A multicentre, double-blind, randomized trial was carried out in 11 Italian Pneumologic Clinics to investigate the therapeutic efficacy and tolerability of doxofylline compared with slow-release theophylline in 139 patients (86 males, 53 females) aged 17-77 years suffering from reversible chronic airways obstruction. The two groups of 69 patients on doxofylline and 70 patients on theophylline did not differ in their baseline clinical and functional parameters. After one week of wash-out, the two drugs were administered orally at a dose of 400 mg twice daily of doxofylline and 300 mg twice daily of theophylline. The treatment and follow-up lasted 28 days. Inhaled salbutamol on demand was allowed in the wash-out week and throughout the trial. The average serum levels at day 14 and 28 were: doxofylline 7.5 and 8.5 micrograms/ml; theophylline 10.4 and 7.95 micrograms/ml respectively. Both drugs significantly increased spirometric parameters (p less than 0.001 for all tests) and significantly reduced salbutamol consumption (p less than 0.001 for both drugs). Doxofylline was better tolerated than theophylline considering either the number of unwanted side-effects: (doxofylline 12; theophylline 37) or number of drop-outs due to side-effects (doxofylline 5; theophylline 10). From these results doxofylline seemed to be a good alternative to theophylline in the treatment of reversible chronic airway obstruction in view of its better safety profile.