In Vitro, Pharmacokinetic, Pharmacodynamic, and Safety Comparisons of Single and Combined Administration of Tiotropium and Salmeterol in COPD Patients Using Different Dry Powder Inhalers.

In vitro Andersen cascade impactor-sized mass (ISM) and aerodynamic fine particle mass (FPM) <5 µm for tiotropium and salmeterol combined in a novel inhalation powder formulation containing 7.5 µg tiotropium/25 µg salmeterol (TSHH) were similar (within ±15%) to reference products containing 18 µg of tiotropium (Spiriva® HandiHaler®) (TioHH) and 50 µg of salmeterol (Serevent® Diskus®) (SalD). The pharmacokinetics (PK), pharmacodynamics, safety, and tolerability of the novel fixed-dose TSHH formulation administered once daily was compared with the single-agent therapies TioHH (once daily [qd]) and SalD (twice daily [bid]) and with the jointly administered combination of TioHH (qd) plus SalD (bid) in a randomized, 22-week, open-label, four-way crossover study in 50 patients with chronic obstructive pulmonary disease (COPD). For tiotropium, TSHH and TioHH were bioequivalent based on mean steady-state plasma area under the plasma concentration-time curves (AUC), while the urinary excretion amount was higher for TSHH and not bioequivalent to TioHH. Tiotropium peak plasma concentrations at steady state (C max,ss) were 40% higher with TSHH. For salmeterol, substantial differences were observed in plasma AUCs and Cmax,ss. No significant differences in 8-h forced expiratory volume in 1 s or forced vital capacity were detected for the TSHH (qd) against the combination of TioHH (qd) with SalD (bid). Maintenance therapy with tiotropium plus salmeterol as TSHH or as the jointly administered reference products is superior to either agent alone, safe, and well tolerated in COPD patients. In vitro results were not predictive of clinical PK findings for both tiotropium and salmeterol for the TSHH dry powder inhaler product.

Effects of short-acting bronchodilators added to maintenance tiotropium therapy.

BACKGROUND: Combining bronchodilators has been shown to be beneficial in patients with COPD. The additive effects of short-acting bronchodilators added to maintenance tiotropium therapy, however, are unknown. METHODS: Following 3 weeks of tiotropium pretreatment, 60 patients with COPD (FEV1 40% of predicted) participated in a randomized, placebo-controlled study to assess add-on bronchodilator effects of ipratropium bromide (40 microg) or fenoterol (200 microg). Short-acting bronchodilators were added as a single dose 2 h and 8 h after tiotropium dosing. Serial lung function tests were performed over 9 h. RESULTS: The peak FEV1 add-on response within 6 h with fenoterol was significantly greater than with placebo (137 mL) or ipratropium (84 mL); the response with ipratropium was slightly but significantly larger than with placebo (52 mL). One hour after the second dose of the test drugs, a similar order of treatment responses was found. The peak FVC add-on response was significant for fenoterol (249 mL) but not for ipratropium (42 mL). CONCLUSIONS: In conclusion, both short-acting bronchodilator classes were effective when added to maintenance treatment with tiotropium. The addition of the beta2-adrenergic fenoterol provided greater additional bronchodilatation than the short-acting anticholinergic ipratropium. This is consistent with the expected effects of combining bronchodilators with different pharmacologic mechanisms. This randomized controlled trial was registered at www.clinicaltrials.gov (NCT00274066).

Effects of tiotropium with and without formoterol on airflow obstruction and resting hyperinflation in patients with COPD.

BACKGROUND: The combination of short-acting beta(2)-agonists and anticholinergics in the treatment of COPD has been well documented, but data on combination of long-acting agents are lacking. METHODS: A randomized, open-label, placebo-controlled, three-way crossover study was conducted comparing 2-week treatment periods of tiotropium alone to tiotropium plus formoterol once or twice daily following a 2-week pretreatment period with tiotropium. Lung function (FEV(1), FVC, and resting inspiratory capacity [IC]) serially over 24 h was measured in 95 patients with stable COPD at baseline and after 2 weeks of each treatment. RESULTS: Mean baseline FEV(1) was 1.05 L (38% of predicted). There was a circadian variation in FEV(1), FVC, and IC at baseline that was maintained during all treatment periods. Average FEV(1) (0 to 24 h) improved by 0.08 L with tiotropium, by 0.16 L with tiotropium plus formoterol once daily, and by 0.20 L with tiotropium plus formoterol twice daily (p < 0.01 for all comparisons). Compared with tiotropium alone, add-on formoterol in the morning produced improvement in FEV(1), FVC, and IC for > 12 h. The second add-on dose of formoterol in the evening caused further improvement in FEV(1) for 12 h, but in FVC and IC for < 12 h. Peak increase in FEV(1) was 0.23 L (22% of baseline) with tiotropium and 0.39 L (37% of baseline) with tiotropium plus formoterol (p < 0.0001). Compared with tiotropium alone, add-on formoterol once and twice daily reduced the use of rescue salbutamol during the daytime (p < 0.01) and with add-on formoterol twice daily also during the nighttime (p < 0.05). The combination of tiotropium and formoterol was well tolerated. CONCLUSION: In the treatment of COPD, there is benefit from adding formoterol once or twice daily to tiotropium once daily in terms of improvement in airflow obstruction, resting hyperinflation, and the use of rescue salbutamol.