Inhalers are essential for managing chronic respiratory conditions, yet their climate impact is often overlooked. Nearly 80% of global inhaler use relies on pressurized metered-dose inhalers (pMDIs), which typically use hydrofluorocarbon (HFC) propellants — potent greenhouse gases.[1] In the U.K., inhalers account for about 3% of the National Health Service’s carbon footprint,[2] making them a target for lower-emission alternatives in healthcare decarbonization efforts.
In May 2025, AstraZeneca received U.K. regulatory approval for a low-carbon version of its widely used chronic obstructive pulmonary disease (COPD) inhaler, Trixeo Aerosphere — a meaningful step toward reducing the climate impact of respiratory care. The new inhaler replaces its traditional propellant with HFO-1234ze(E), a next-generation alternative with 99.9% lower climate impact, while maintaining the same safety and efficacy.[3] It is expected to become available in the U.K. later this year, with plans to expand to the U.S. market in the future.
“The transition of Trixeo to the propellant with near-zero [climate impacts] means that healthcare professionals can focus on optimising outcomes for their COPD patients based on clinical need, while also supporting climate goals,” said Omar Usmani, professor of respiratory medicine at Imperial College London, in a statement. “Clinicians and their patients shouldn’t feel that they have to choose between the most appropriate treatment and the planet.”[4]
This approval is part of AstraZeneca’s broader Ambition Zero Carbon strategy to transition its entire pMDI portfolio to a near-zero emission propellant by 2030. Backed by over $500 million in investment — and delivered at no additional cost to patients or healthcare systems[5] — this initiative sets an important precedent for how the healthcare sector can reduce emissions without compromising access or outcomes.
While other pharmaceutical companies are pursuing similar innovations, AstraZeneca’s approval shows how climate and clinical priorities can advance together.
If you are interested in reading more about corporate work to lower negative environmental impacts, please see other EP Insights from Terra Alpha here.
[4] AstraZeneca: Trixeo Aerosphere approved in the UK as first inhaled respiratory medicine using next-generation propellant with near-zero Global Warming Potential