Lung deposition of two different ICS/LABA combinations with Dry Powder Inhaler (DPI) in asthmatic patients using Functional Respiratory Imaging (FRI)

Introduction: FRI is a novel computational fluid dynamics-based technique using in vitro formulation characteristics and patientʼs lung CT scan to simulate aerosol deposition.

Aim: to compare the lung deposition patterns of extrafine beclometasone/formoterol combination (Foster), administered through NEXThaler, with fluticasone furoate/vilanterol (Relvar), administered through Ellipta.

Methods: in vitro drug delivery parameters from optimal profiles with a DPI, as defined by ERS/ISAM Task Force, were incorporated by FRI into lung CT scan images of 20 asthmatic patients to calculate aerosol airway deposition patterns.

Results: Intrathoracic deposition with NEXThaler was higher compared with Ellipta both for ICS (40.09 ± 5.53% vs. 12.91 ± 5.05%) and LABA (36.49 ± 5.70% vs. 25.82 ± 6.15%). The difference in peripheral deposition was even greater both for ICS (24.69 ± 3.38% vs. 4.97 ± 1.96%) and LABA (21.94 ± 3.42% vs. 13.02 ± 3.02%), reflecting the lower MMAD of Foster NEXThaler. Consequently, central to peripheral (C/P) ratio with NEXThaler was lower than with Ellipta both for ICS (0.63 ± 0.15 vs. 1.63 ± 0.54) and LABA (0.67 ± 0.17 vs. 0.99 ± 0.25). Notably, the two components of BDP/FF showed a similar C/P distribution pattern, while this was not observed with FluF/Vil.

Conclusions: FRI deposition data show a much higher lung deposition, with a lower central to peripheral ratio, with extrafine BDP/FF NEXThaler than with non-extrafine FluF/Vil Ellipta, suggesting that the extrafine formulation is superior to larger particle formulations in delivering both ICS and LABA consistently to both the large and small airways.