This is a phase 3b, multicentre, randomized, double-blind, single-dose crossover study comparing the safety and tolerability of HFO MDI with HFA MDI delivered in participants with well controlled or partially controlled asthma defined as an ACQ-5 score < 1.5.Eligible participants are at least 18 years of age and no older than 45 years of age and are required to have asthma as defined by GINA guidelines (GINA 2022). Participants are required to be well controlled or partially controlled on their current treatment for asthma, including, low-dose ICS daily or low-dose ICS/formoterol as needed (not approved in the US), or SABA as needed, or low-dose ICS whenever SABA as needed is used. The primary objective is to assess the potential change in FEV1 induced by HFO MDI as compared with HFA MDI in participants with asthma.~This study will be conducted at approximately 5 sites in the US and will randomize approximately 52 adult participants to achieve 46 completers.~The study will be conducted for a maximal 37 days and will comprise:~A screening period approximately 14 (±2) days prior to first dosing~Two treatment periods of 1 day each, with a 3 to 12-day washout period between the 2 treatment periods~A final safety follow-up visit via telephone contact 3 to 7 days after the final dose administration in Treatment Period 2~Single dose study treatment will be administered via MDI device as 4 inhalations:~Treatment A: HFO propellant only MDI; 4 inhalations per dose - test formulation~Treatment B: HFA propellant only MDI; 4 inhalations per dose - reference formulation
A study to assess bronchospasm potentially induced by HFO MDI as compared with HFA MDI in participants with well controlled or partially controlled asthma