Sustaining treatment for asthma and COPD patients while minimizing carbon footprint: effect of HFA-152a and HFA-134a on lung mucociliary clearance

Chiesi is developing a portfolio of pMDI products containing a new propellant (HFA-152a) with lower global warming potential (GWP) compared to currently marketed pMDIs with HFA-134a, aiming to maintain the range of patient-centred treatment options for asthma and COPD while lowering environmental impact. This was a phase I, randomised, open-label, 2-way cross-over study conducted in 20 healthy volunteers (HV) to assess the effect of HFA-152a and HFA-134a on mucociliary clearance (MCC). Each HV underwent two 8-day treatment periods of twice daily administrations of a placebo formulation containing HFA-152a or HFA-134a. Gamma scintigraphy imaging was performed on the day prior to the 1^st administration and on Day 8 after the last administration. Image acquisition lasted 4 hours from the inhalation of a 99mTc radioaerosol and provided an estimation of the percent particle retention (PPR) over time. The MCC was assessed as PPR from the whole right lung at 2 hours (PPR_2h) and 4 hours (PPR_4h) post-inhalation. No statistically significant change from baseline in PPR_2h or PPR_4h was evidenced for either of the two formulations. No significant difference between the two propellants on the change from baseline in PPR_2h and PPR_4h at Day 8 was shown. Thus, the repeated inhalation of HFA-152a or HFA-134a had no impact on lung MCC. Safety and tolerability were good and comparable between both study treatments and lung function remained stable. This study supports the propellant switch from the current HFA-134a to the HFA-152a propellant with lower GWP and the timely introduction of treatment options enabling seamless and safe transition for patients.