Targeting of Inhaled Therapeutics to the Small Airways: Nanoleucine Carrier Formulations

Current dry powder formulations for inhalation deposit a large fraction of their emitted dose in the upper respiratory tract where they contribute to off-target adverse effects and variability in lung delivery. The purpose of the current study is to design a new formulation concept that more effectively targets inhaled dry powders to the large and small airways. The formulations are based on adhesive mixtures of drug nanoparticles and nanoleucine carrier particles prepared by spray drying of a co-suspension of leucine and drug particles from a nonsolvent. The physicochemical and aerosol properties of the resulting formulations are presented. The formulations achieve 93% lung delivery in the Alberta Idealized Throat model that is independent of inspiratory flow rate and relative humidity. Largely eliminating URT deposition with a particle size larger than solution pMDIs is expected to improve delivery to the large and small airways, while minimizing alveolar deposition and particle exhalation.

Targeting of Inhaled Therapeutics to the Small Airways: Nanoleucine Carrier Formulations

Current dry powder formulations for inhalation deposit a large fraction of their emitted dose in the upper respiratory tract where they contribute to off-target adverse effects and variability in lung delivery. The purpose of current study is to design a new formulation concept that more effectively targets inhaled dry powders to the large and small airways. The formulations are based on adhesive mixtures of drug nanoparticles and nanoleucine carrier particles prepared by spray drying of a co-suspension of leucine and drug particles from a nonsolvent. The physicochemical and aerosol properties of the resulting formulations are presented. The formulations achieve 93% lung delivery in the Alberta Idealized Throat model that is independent of inspiratory flow rate and relative humidity. Largely eliminating URT deposition with a particle size larger than solution pMDIs is expected to improve delivery to the large and small airways, while minimizing alveolar deposition and particle exhalation.

Carrier Effect in Development of Rifampin Loaded Proliposome for Pulmonary Delivery: A Quality by Design Study

Purpose: Pulmonary Tuberculosis (TB) is a worldwide life-threatening infection. The recommended anti-TB regimen contains oral administration of classical first-line drugs such as rifampin for 6-24 months which often leads to low patient compliance due to high adverse effects; therefore, lung localized pulmonary delivery of anti-TB agents may be a suitable alternative. Proliposomes free-flowing powders are well-known carriers for lung delivery since they can form liposomes by hydration. Liposomes are safe and useful carriers for lung delivery due to their phospholipid structure. Methods: Porous lactose and mannitol as proliposome carriers were prepared by spray drying technique using sucrose and citric acid as templating agents. Design expert® software was used to develop forty formulations due to the porous and non-porous carriers, which were characterized with respect to their weight yield, density, and flowability. Rifampin-loaded hydrated liposomes were produced and evaluated for size, morphology, loading capacity and encapsulation efficiency. The optimized proliposomes in vitro release and aerosolization properties were evaluated. Solid-state analysis was confirmed by Differential Scanning Calorimetry (DSC). Results: Porous lactose surface area was 80 folds higher than non-porous one, respectively. Optimized porous-based proliposome indicated the acceptable aerosolization properties, including mass median aerodynamic diameter (MMAD) of 6.21±0.36 µm and fine particle fraction (FPF) of 9.17±0.18% with a fast rifampin release (80%) within one hour. DSC results proved that there was no change in the solid-state of rifampin during the production process. Conclusion: Hence, it seems; rifampin loaded inhalable proliposomes may be a suitable system for delivering liposomal rifampin into the lungs.