Randomisation and blinding
2:1 (SpiroDex:Dex) randomisation was performed utilising a coin toss method to achieve the desired probability. Multiple coin flips per patient (maximum of 6 flips per patient, or until ≥ 3 heads were recorded) were used to achieve a 2:1 randomisation. Further information on this method of randomisation is available in the supplementary information. After randomisation the group allocation was concealed in an opaque sealed envelope which was opened prior to the initiation of treatment. The group allocation was known only to the treating non-trial physician. The patients and the trial investigators recording the trial parameters were blinded to group allocation. Blank pills were used as the placebo pills.