Comparison of the efficacy, tolerability, and safety of formoterol dry powder and oral, slow-release theophylline in the treatment of COPD.

STUDY OBJECTIVE: To compare the efficacy, tolerability, and safety of therapy with formoterol and oral slow-release theophylline (THEO) in patients with COPD.

DESIGN: A randomized, parallel-group study, with double-blind arms for formoterol and placebo (PL) and an open arm for oral slow-release THEO administered in individual doses on the basis of plasma concentrations.

SETTING: Eighty-one centers worldwide.

PATIENTS: Eight hundred fifty-four patients with symptomatic COPD.

INTERVENTION: Comparison of twice-daily inhaled formoterol dry powder (12 or 24 microg), PL, and THEO (individualized doses) over 12 months.

MEASUREMENTS AND RESULTS: Compared to PL, doses of formoterol and THEO both significantly improved the area under the curve for FEV(1) measured over a period of 12 h following the morning dose of study medication at 3 and 12 months (p < 0.001 for all comparisons). Therapy with formoterol, 12 microg, was significantly more effective than that with THEO (p < or = 0.026). Formoterol significantly reduced the percentage of "bad days" (i.e., days with at least two individual symptom scores > or = 2 and/or a reduction in peak expiratory flow from a baseline of > 20%; p < or = 0.035 vs. PL and THEO), and the use of salbutamol rescue medication (p < or = 0.003 vs PL) over the whole treatment period, while the effect of THEO was similar to that of PL. Therapy with formoterol and THEO was more effective than PL at improving quality of life for > 12 months (p < or = 0.030). Treatment-related adverse events and discontinuations were more frequent among patients receiving THEO than among those receiving formoterol.

CONCLUSIONS: Long-term treatment with inhaled formoterol dry powder is more effective and better tolerated than treatment with therapeutically appropriate doses of oral slow-release THEO in symptomatic patients with COPD.