How to Develop Method for Pulmonary Dry Powder Inhalers

Dry powder inhalers (DPIs) are the system in which devices used to administrate a dry powder formulation of an active drug is delivered for local or systemic effect via the pulmonary route. DPIs have several advantages over other methods of pulmonary drug delivery, for example, direct delivery of the drug into the deep lungs utilizing the patient's respiration and are increasingly being explored as a mechanism for the delivery of systemic drugs. Successful delivery of drugs into the deep lungs depends on the integration between powder formulations and the device performance. Development requires that current DPIs demonstrate in vitro performance and reliability. However, questions remain about the ability to interchange DPIs and the effects of different clinical states and patient characteristics.