Drug delivery to the lungs from dry powder inhalers: Impact of the inhaler device and patient inhalation manoeuvre

Description

Inhaled therapy plays an important role in the management of airway
diseases such as, asthma and chronic obstructive pulmonary disease
(COPD). Peak inhalation flow has been considered for so many years
by the inhalation scientists as the most important parameter governing
drug delivery to the lungs from DPIs, however, many patients especially
those with low lung capacity are unable to generate sufficient inhalation
flow to deaggregate the powder formulation to get most of the dose
into their lungs. In addition to the peak inhalation flow (MIF), this
presentation will focus on other inhalation parameters such the inhaled
volume (Vin) and the acceleration rate of the air flow at the start of
the inhalation manoeuvre (ACIM) and to investigate their impact on
the dose emission and aerodynamic characteristics from two inhaler
devices (low resistance: Ombrez Breezhaler and high resistance device:
Easyhaler).
Traditionally, the in-vitro total emitted dose (TED) and its particle size
distribution via a DPI is measured using standard pharmacopoeial
methods and is widely accepted by the regulatory authorities. The
method involves simulating an inhalation profile through a dry powder
inhaler (DPI) using a vacuum pump to emit a dose and collect it into
a cascade impactor. The measured particle size distributions represent
particle deposition into different zones of the lungs. Humans cannot
replicate the square wave generated by a vacuum pump; nor can
the majority of patients achieve the pharmacopoeia-recommended
inhalation parameters (4 KPa pressure drop and 4 Litres inhaled
volume). These limitations are becoming more problematic as the use of
DPIs are extended to, for example: paediatric, who do not have the lung
capacity of a healthy adult. In this presentation we will discuss an Exvivo
method that replaces the vacuum pump used in pharmacopoeia
methods with a patient inhalation profile to provide information on the
TED that the patient would have inhaled in real life.
Audience Take Away:
• The difference between different dry powder inhalers (DPIs) and
how the design of a DPI device affects drug delivery to the lungs.
• Should we look for a threshold inhalation flow to deaggregate the
powder formulation or the peak inhalation flow when choosing an
inhaler device?
• Understand the important inhalation manoeuvre parameters to
maximize drug delivery to the lungs, especially for patients with
low lung capacity.
• Understand how to use a DPI more efficiently to get most of the
inhaled dose into the lungs.

Period	6 Jun 2018
Event title	2nd Global Conference on Pharmaceutics & Drug Delivery Systems
Event type	Conference
Conference number	2
Location	Rome, ItalyShow on map
Degree of Recognition	International