Executive Summary:

Sustainability is a hot topic at the moment and the inhaler industry is busy making changes to their pMDI devices to suit more sustainable propellants. It is great to see all the hard work going into reducing the environmental impact of the gases in these devices. However, it led us to thinking about the next steps after the propellent changes and how the sustainability of the physical devices can be further improved. In many cases the overall device has largely remained unchanged for many years.

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HD’s solution to improve sustainability is to create a pMDI with reusable plastic elements, which we’ve calculated would eliminate approximately 80% of the current annual plastic waste, not to mention the substantial reduction in packaging, storage and transport which further reduces the carbon footprint as well as costs involved.

Initially HD conducted a Public and Patient Involvement (PPI) activity, jointly organised by Keele University and JG Technology Management, to capture the thoughts of people who use inhalers, and people who care for people who use inhalers.

The session was incredibly insightful, with new ideas being expressed by the entire group, confirming our prior assumptions, and sparking new ways of thinking. This PPI session was a pivotal moment in building confidence with our vision for this project.

Our team began investigating reasons that prevent simply replacing the current canisters. The key reasons are that the housing nozzle eventually becomes blocked after a period of time, preventing a repeatable measured dose reaching the user, and a build-up of the residual drug can become toxic. Understanding these points set us off looking at how we could redesign the inhaler to separate the nozzle from the mouthpiece body to allow only the nozzle to be disposed of with the empty canister.

Safety was of course our biggest concern, and we were keen not to introduce new risks to a very familiar device. Some of the highest ranked device risks that we analysed included choking hazards, use error and component failures preventing a new canister being inserted.

Alongside safety, another risk was that, as the classic pMDI canister is so standardised and established in the industry, that changing the design of it could impact on the potential uptake of the system. With this in-mind, one of the requirements which we set was that the nozzle should fit to the canister without any changes to the existing canister components.

Involving all of the team at HD over various brainstorm sessions, we aimed to think of as many methods of attaching the nozzle to the canister as possible. With 15-20 feasible solutions, we scored them in an idea judgement matrix, using a number of criteria to assess the best idea.

Here are a selection of risks, and design features that we included to mitigate them:-



Aside from these technical features, the form of the inhaler has seen sharp edges replaced with softer, rounded edges, which make the inhaler feel better in the hand and much more comfortable to carry in pockets etc.

After all the work we’ve carried out on this project, we’re left with a sustainable pMDI system that would feel like a relatively small change to users, but provide an impressive annual plastic reduction of approximately 80%. Across the UK and USA alone, this would be in the region of 1,500 tonnes of plastic! We’ve already gained a high amount of interest from the NHS, who can see the sustainability improvements and potential cost savings as well. We look forward to gaining support to take this project further and hopefully see this making a big difference to the sustainability of future pMDIs.


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