The St George 's Respiratory Questionnaire score improved substantially in the AKL1 treatment group by a mean ( SD ) of -7.7 ( 11.7 ) versus worsening in the placebo group ( +1.5 [ 9.3 ] ) , with mean difference in change of -9.2 ( 95 % confidence interval : -19.0 to 0.6 ; P = 0.064 ) .