This study is not being conducted in the United States.

This study is designed to provide efficacy and safety data for formoterol 10µg twice-a-day (b.i.d.) delivered by the Certihaler in patients with chronic obstructive pulmonary disease (COPD). This study is also designed to compare the efficacy and safety of therapy with formoterol (Certihaler)10µg b.i.d. added to tiotropium (HandiHaler) 18µg once daily (o.d.) compared with tiotropium (HandiHaler) 18µg o.d. monotherapy, and to compare the safety and efficacy of formoterol 10µg b.i.d. (Certihaler) with tiotropium 18µg o.d. (HandiHaler).

Inclusion Criteria:

• Co-operative males or females with a diagnosis of moderate COPD as per the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria with an age at onset ≥ 40 years.
• Current or previous smokers with a smoking history of ≥ 10 pack-years. Ten pack-years is defined as 20 cigarettes a day for 10 years, or 10 cigarettes a day for 20 years etc.
• Pre-bronchodilator forced expiratory volume in one second (FEV1) < 70% of patient's predicted normal value and ≥ 1.00 L, with FEV1/forced vital capacity (FVC) < 70% at Visit 2.
• A total symptom score from the patient diary of more than 0 on at least 4 of the last 7 days prior to Visit 3

Exclusion Criteria:

• Pregnant women, nursing mothers, and females of childbearing potential, regardless of whether or not sexually active, who do not use a reliable contraceptive method (oral, mechanical, subcutaneous or surgical contraception).
• Patients who have been hospitalized for an acute exacerbation of their airway diseases in the month prior to Visit 1 or during screening.
• Patients who have had a respiratory tract infection within 1 month prior to Visit 1. Patients who develop a respiratory tract infection during the screening period must discontinue from the trial, but will be permitted to re-enroll at a later date (at least 1 month after the resolution of the respiratory tract infection).
• Patients with concomitant pulmonary disease including a history of cancer (all), pulmonary tuberculosis or congenital bronchiectasis.
• History of asthma