Dry powder inhaler design and particle technology in enhancing Pulmonary drug deposition: challenges and future strategies

Abstract

Objectives: The efficient delivery of drugs from dry powder inhaler (DPI) formulations is associated with the complex interaction between the device design, drug formulations, and patient's inspiratory forces. Several challenges such as limited emitted dose of drugs from the formulation, low and variable deposition of drugs into the deep lungs, are to be resolved for obtaining the efficiency in drug delivery from DPI formulations. The objective of this study is to review the current challenges of inhaled drug delivery technology and find a way to enhance the efficiency of drug delivery from DPIs.

Methods/evidence acquisition: Using appropriate keywords and phrases as search terms, evidence was collected from the published articles following SciFinder, Web of Science, PubMed and Google Scholar databases.

Results: Successful lung drug delivery from DPIs is very challenging due to the complex anatomy of the lungs and requires an integrated strategy for particle technology, formulation design, device design, and patient inhalation force. New DPIs are still being developed with limited performance and future device design employs computer simulation and engineering technology to overcome the ongoing challenges. Many issues of drug formulation challenges and particle technology are concerning factors associated with drug dispersion from the DPIs into deep lungs.

Conclusion: This review article addressed the appropriate design of DPI devices and drug formulations aligned with the patient's inhalation maneuver for efficient delivery of drugs from DPI formulations.

Keywords: Computational modelling; DPI device design; Drug formulation; Lung deposition; Particle technology.

Fig. 1

Mechanism of drug dispersion from dry powder inhaler (Redrawn from Tiano and Dalby [20])

Fig. 2

Mechanisms of dispersion of the powder as aerosol inside an inhaler (drug particle in blue, carrier particle in orange)

Fig. 3

The roles of computational modelling in developing of DPI systems

Fig. 4

The calculated concentrations of tobramycin across the bronchial tree for three types of inhalations—uninstructed, instructed fast, and instructed slow—during tobramycin inhalation powder (TIP) and tobramycin inhalation solution inhalation sessions, based on three single-study participants and three out of the nine CT models examined [149]