Differences between treatments (indacaterol plus tiotropium–tiotropium plus placebo) in FEV1 AUC5min–8h and trough FEV1 in patient subgroups analysed according to COPD severity, smoking status and ICS use*
| Differences between indacaterol + tiotropium versus tiotropium + placebo | ||||
| FEV1 AUC5min–8h | Trough FEV1 | |||
| Study 1 | Study 2 | Study 1 | Study 2 | |
| COPD severity† | ||||
| Moderate‡ | 120 ml (90 to 160) (n=233/237)§ | 130 ml (90 to 160) (n=247/237) | 90 ml (50 to 130) (n=259/260) | 90 ml (60 to 120) (n=261/258) |
| Severe or very severe | 130 ml (100 to 160) (n=272/267) | 110 ml (80 to 140) (n=283/267) | 70 ml (30 to 110) (n=302/289) | 60 ml (30 to 90) (n=304/306) |
| Smoking status | ||||
| Ex-smoker | 120 ml (90 to 150) (n=300/324) | 140 ml (110 to 170) (n=331/285) | 70 ml (40 to 110) (n=335/350) | 80 ml (60 to 110) (n=352/322) |
| Current smoker | 130 ml (90 to 170) (n=205/180) | 90 ml (50 to 120) (n=199/219) | 80 ml (40 to 130) (n=226/199) | 60 ml (20 to 90) (n=213/242) |
| ICS use | ||||
| ICS non-users | 120 ml (90 to 160) (n=242/236) | 140 ml (100 to 170) (n=229/251) | 70 ml (30 to 110) (n=271/260) | 90 ml (60 to 120) (n=244/274) |
| ICS users | 130 ml (100 to 160) (n=263/268) | 100 ml (70 to 140) (n=301/253) | 80 ml (50 to 120) (n=290/289) | 60 ml (30 to 90) (n=321/290) |
Data are least squares means with 95% CI in parentheses. All treatment contrasts significant at p≤0.001.
↵* The interaction term for treatment by subgroup was non-significant in all cases (p>0.1).
↵† Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2007.
↵‡ Includes one patient (study 1, tiotropium group) with mild severity.
↵§ Patient numbers are for indacaterol + tiotropium and tiotropium groups, respectively.
AUC5min–8h, area under the curve from 5 min to 8 h post dose; COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; ICS, inhaled corticosteroid.