Co-polymer Stabilizers for Pressured Metered Dose Inhalers (pMDIs)

Case ID:

A series of novel co polymer surfactants with the general structure LAmEOnLAm were developed along with a Colloidal Probe Microscopy (CPM) method to optimize the surfactant composition using adhesion forces to improve stabilization of drug dispersions. This expands the range of biomolecules and micronized drug particles that can be formulated with pMDIs.  New pharmaceutical compositions can be tested and the ideal co-polymer surfactant composition optimized through quantitative measurement of cohesive forces. The biodegradable and biocompatible lactide-based amphiles chosen can stabilize drug dispersions in HFA propellants used in pressurized metered dose inhaler (pDMIs) formulations better than existing excipients.

Competitive Advantage
Improved Deep Lung Deposition
Increased Suspension Stability
Expanded range of insoluble inhaler drugs

Benefit Analysis
pMDIs are still the most frequently prescribed inhaler device in the world and various spacer combinations and breath-actuated devices have recently improved patient compliance. The technologies developed at WSU directly address the challenge of reformulation pMDI drugs from traditional CFC propellants to more environmentally friendly Hydrofluorakane (HFA) propellants. 

While several HFA propellants have been developed, especially for new and insoluble active pharmaceutical ingredients there is still a limited selection of excipients compatible with HFA and safe for human use.  Very specific size requirements and strong interactions between particles and intrinsic barriers need to be overcome in order to deliver therapeutics to the lung epithelia. The WSU inventions greatly expand the range of therapeutics that can be delivered using pMDIs through compositions and methods to achieve optimal formulations.

Stage of Development: Pre-clinical
Biocompatibility & long term stability studies
Complete aerosol characterization using Anderson Casade Impactor (ACI) and other methods

Patent Status
12/738,826 “Co-polymer Stabilizers For Hydryfluoroalkane Dispersions” - Notice of Allowance

2008 "Biocompatible and Biodegradable Copolymer Stabilizers for Hydrofluoroalkane Dispersions: A Colloidal Probe Microscopy Investigation" L. Wu & S.R.P. da Rocha, LANGMUIR, 23(24), pp 12104-12110.

2007 “Biocompatible, lactide-based surfactants for the CO2-water interface: High-pressure contact angle goniometry, tensiometry, and emulsion formation” B. Bharatwaj et al. LANGMUIR, 23(24) pp 12071-12078


Patent Information:
For Information, Contact:
Nicole Grynaviski
Commercialization Principal
Wayne State University
Sandro da Rocha
Libo Wu
Drug Delivery