Patent ID: 6571793
Filing Date: 2003-06-03
Classification: A61M

Abstract:
A method for optimizing an electrostatically dosed dry powder inhaler (EDPI) for utilization of a prepared pre-metered electro-dose consisting of an electro-powder, comprising the steps ofarranging a measurement set-up for measurement of parameters affecting a systemic delivery or local lung delivery of a pre-metered electro-dose from a dry powder inhaler (DPI) including analysis of dose de-agglomeration, particle size distribution as well as uniformity of dose together with pressures times and flows according to USP; adjusting said DPI for a systemic or a local lung setting with respect to an activation pressure and a closing pressure having a DPI with a 20 to 60 liters/minute inhalation air flow for a systemic delivery setting and 20 to 80 liters/minute for a local lung setting; adjusting a de-agglomeration power between 0.1 and 6 watts to be used in said DPI by optimizing a pressure drop and an inhalation flow rate by changes to a mouthpiece and/or a device member and their relation to each other; adjusting said activation pressure between 0.5 and 4 kPa and said closing pressure between 0.5 and 4 kPa to eliminate low power at the start and end of the inhalation; verifying that said DPI meets specifications set regarding the de-agglomeration power and said activation and closing pressures together with timings within an active time of the DPI; verifying that a de-agglomeration difference, expressed in percent using an expression 100[1âˆ’ de-agglomeration(Q1 kpa/de-agglomeration(Q)], is not more than 50%, where Q1 kPa represents a pressure drop over the inhaler device reduced to 1 kPa and Q represents a reference pressure drop; verifying that a uniformity of dose meets a uniformity standard; and verifying and optimizing a not approved DPI by further adjusting said DPI and/or electro-dose to meet specifications of an EDPI.