“Greener” choices in inhalers garner increasing pharma, device company support

To address global climate change, Cynthia Siego writes how some pharma and device makers have developed pressurized Metered Dose Inhalers (pMDI) using propellants with lower global warming risk to treat asthma and COPD patients.


umerous companies, including dozens of pharmaceutical companies, have set net-zero emissions targets following COP26. The healthcare industry is a particularly important stakeholder as climate change, health, and medicine are inextricably linked.

Rising global temperatures are associated with several negative health impacts, including asthma, cardiovascular diseases, infectious diseases, and other heat-related illnesses. Yet healthcare is among the most carbon-intensive service sectors in the US economy.

Given the primary goal for the healthcare industry – saving patients’ lives and improving health outcomes – companies have to account for their contributions to climate change. Some pharmaceutical and medical devices companies have taken up the challenge to innovate with more environmentally friendly alternatives to their product.

For example, some have developed pressurized Metered Dose Inhalers (pMDI) using propellants with lower global warming risk to treat asthma and COPD patients.

Lower Carbon Impact Inhalers

Metered Dose Inhalers (MDIs), containing hydrofluoroalkane (HFA; typically, HFA134a or HFA227ea) propellants, are widely prescribed in the US for acute symptoms and long-term management of asthma and COPD.

The propellant is required to atomize the drug formulation, which helps enable accurate and repeatable dosing of active agents in each puff. HFA—a potent greenhouse gas—has been scheduled to be phased down under the Kigali Amendment to the Montreal Protocol. This has spurred innovations to facilitate transitions from HFA MDIs towards alternatives with lower carbon footprints, such as dry powder inhalers (DPI, no propellant).

We analyzed 2019 Medicare Part D Drug Spending Data combined with published data on inhalers’ carbon footprints to broadly demonstrate the potential impact of switching from HFA MDIs to DPIs. We focused on two commonly prescribed type of inhalers: Albuterol Sulfate (short-acting beta-agonists, SABA), Fluticasone Propionate (inhaled corticosteroids, ICS).

This analysis illustrates the economic and environmental implications of switching from HFA MDIs to DPIs

as well as the potential value of investments in lower carbon footprint alternatives to HFA MDIs.

We found that only approximately 4.8% of Medicare Part D beneficiaries who received Albuterol and 10.9% who received Fluticasone inhalers use the DPI version. This is somewhat comparable to the proportion of DPI use in the UK (6% SABA, 6% ICS), but far behind that of Sweden (90% SABA, 85% ICS).

Meanwhile, the average total annual drug spending per beneficiary using DPI tends to be lower compared to those using the HFA MDI proportionate.

Economic and Environmental Impact of Switching to Lower Carbon Impact Inhalers

Looking at current HFA MDI use, for every 10% of Albuterol HFA MDIs replaced with Albuterol DPI, the total annual drug spending (the amounts paid by Medicare Part D and the beneficiary) is estimated to be reduced by $16.6M, while 122 kt CO2e (9.6% of Albuterol inhalers’ carbon footprint) emission could be averted annually.

Similarly, every 10% of Fluticasone HFA MDI substituted with its DPI counterpart, the total annual cost projected to be reduced by $6.4M and 8 kt CO2e (9.5% of Fluticasone inhalers carbon footprint) would be saved annually.

Reducing the proportion of Albuterol HFA MDI use to 10%, as in Sweden, would yield carbon savings of 1,096 kt CO2e annually, through reduction in carbon footprint at the user phase (71%) and end-of-life stage (27%) of the device, while also delivering a $148M reduction in annual prescription cost.

Applying the proportion of Swedish ICS MDI use (15%) to Fluticasone HFA MDI in the Medicare Part D population results in an estimated reduction of 69 kt CO2e annually (60% from user phase, 31% from end-of-life stage, 9% from manufacturing), and $53M prescription cost savings annually.

Implications of Environmentally Friendly Medicine

Thus, if prescribers are able to switch from HFA MDIs to DPI options within each therapeutic category, both major economic savings and substantial carbon reductions could be made. DPIs might not be the best solution for all patients clinically, as DPI’s require patients to have sufficient respiratory force to inhale the drugs; but even a small transition could still yield meaningful results.

Aside from incentivizing the use of currently available DPIs, these results also point towards the large potential market for more climate-friendly alternatives to traditional MDIs, which is only likely to expand given the growing awareness and commitment to alleviating climate change.

Some companies have spearheaded the development of alternatives, such as pMDIs at comparable carbon footprints to typical DPIs.

This spurt of green innovations, in turn, sends stronger market signals to policymakers that ramping up their national agenda to slow climate change includes achievable goals at a reasonable cost, as well as provides confidence to investors in supporting greener initiatives.

Additionally, green medical innovations can provide choices to the patients on the type of treatment that works best for them—clinically and socially; therefore, likely encourages more open conversations between prescribers and patients on the appropriateness of treatments while encouraging proper use and less waste.

This analysis shows but one example of how greener choices and innovation could help alleviate the destructive climate change impacts on health and how healthcare industry could contribute to a more sustainable future.