The novel, easy-to-use, breath-actuated fluticasone propionate/salmeterol multidose dry powder inhaler (MDPI) (AirDuo RespiClick®) was recently approved in the USA for twice-daily treatment of asthma in patients aged ≥ 12 years. This inhaled corticosteroid (ICS) and long-acting β2-adrenoreceptor agonist (LABA) combination treatment is available in low-, mid- and high-dosage formulations (55/14, 113/14 and 232/14 μg, respectively). In 12-week, phase III trials in patients aged ≥ 12 years with persistent asthma, all three dosages of fluticasone propionate/salmeterol MDPI treatment produced significant improvements in lung function and other asthma symptoms compared with fluticasone propionate MDPI monotherapy or placebo MDPI. In a 26-week, phase III trial in this patient population, mid- and high-dosage fluticasone propionate/salmeterol MDPI were noninferior to mid- (250/50 μg) and high- (500/50 μg) dosage fluticasone propionate/salmeterol DPI (Advair Diskus®), respectively, in terms of improvements in lung function. Treatment-emergent adverse events (TEAEs) with fluticasone propionate/salmeterol MDPI were mostly of mild to moderate severity, with no severe TEAEs deemed to be treatment related. Although long-term pharmacovigilance is required to fully establish its safety, given the ease of use and favorable characteristics of the device and its clinical efficacy at relatively low metered doses of the active moieties, fluticasone propionate/salmeterol MDPI is an important emerging treatment option in patients aged ≥ 12 years with asthma.

The in-vitro aerosol performance of two combination dry powder inhaler (DPI) products, Foster® NEXThaler® and Seretide® Diskus® were investigated with single particle aerosol mass spectrometry (SPAMS). The in-vitro pharmaceutical performance is markedly different for both inhalers. Foster® NEXThaler® generates a higher fine particle fraction (FPF <5 μm) and a much higher relative extra fine particle fraction (eFPF <2 μm). In terms of the composition of the aerodynamic particle size distribution (APSD), it could be verified with SPAMS that overall Foster® NEXThaler® emits a significantly higher number of fine and extra fine particles with a median aerodynamic diameter (MAD) of 2.1 μm while Seretide® Diskus® had a larger MAD of 3.1 μm. Additionally, the interactions between the two active pharmaceutical ingredients (APIs) in both products are different. While Seretide® Diskus® emits a significant (37%) number of co-associated API particles, only a negligible number of co-associated API particles were found in Foster® NEXThaler® (<1%). A major difference with Foster® NEXThaler® is that it contains magnesium stearate (MgSt) as a second excipient besides lactose in a so-called 'dual excipient' platform. The data generated using SPAMS suggested that nearly all of the beclomethasone dipropionate particles in Foster® NEXThaler® also contain MgSt and must therefore be co-associated with this additional excipient. This may help explain why beclomethasone dipropionate in Foster® NEXThaler® forms less particle co-associations with the second API, formoterol fumarate, shows a lower cohesive strength in respect to beclomethasone itself and why both APIs exhibit superior detachment from the carrier as evidenced by the increased eFPF and smaller MAD.

This was a randomized, double-blind, crossover, clinical-end-point pilot study examining the hypothesis that inhaled fluticasone propionate decreases exhaled nitric oxide (eNO) concentrations within a week of beginning treatment and shows evidence of dose separation across the marketed dose range. Subjects had a ≥6-month history of asthma and screening eNO ≥60 parts per billion. At the start of each treatment period, eNO was ≥55 parts per billion, and forced expiratory volume in 1 second was ≥50% predicted. Subjects attended a clinic visit daily on consecutive mornings during each of 3 1-week treatment periods to measure eNO and receive once-daily doses of 100/50, 250/50, or 500/50 fluticasone propionate/salmeterol combination product (Advair® Diskus). Daily eNO value recorded was the highest of 3 measurements; 1 inhalation of treatment was then administered. Procedures were repeated for 3 treatment cycles, separated by 14-day minimum washouts. A total of 105 subjects were screened; 22 were randomized; and 17 completed all treatments. Mean percentage eNO decrease (standard deviation) from day 1 baseline for each treatment period was 36.6 (±18.7), 45.3 (±16.5), and 54.6 (±12.5) with Advair® 100/50, 250/50, and 500/50, respectively. Mean percentage decrease in eNO across each treatment (dose) was modeled using a mixed-model ANOVA. Although the overall treatment was significant (P = .0015), because of the relatively small sample size and within-subject variability, only the 100/50 vs 500/50 (P = .0003) and 250/50 vs 500/50 (P = .047) treatments were significantly different.

Particle co-associations between the active pharmaceutical ingredients fluticasone propionate and salmeterol xinafoate were examined in dry powder inhaled (DPI) and metered dose inhaled (MDI) combination products. Single Particle Aerosol Mass Spectrometry was used to investigate the particle interactions in Advair Diskus® (500/50 mcg) and Seretide® (125/25 mcg). A simple rules tree was used to identify each compound, either alone or co-associated at the level of the individual particle, using unique marker peaks in the mass spectra for the identification of each drug. High levels of drug particle co-association (fluticasone-salmeterol) were observed in the aerosols emitted from Advair Diskus® and Seretide®. The majority of the detected salmeterol particles were found to be in co-association with fluticasone in both tested devices. Another significant finding was that rather coarse fluticasone particles (in DPI) and fine salmeterol particles (both MDI and DPI) were forming the particle co-associations.