Despite receiving a reduced glucocorticoid dose , patients in the mepolizumab group , as compared with those in the placebo group , had a relative reduction of @ % in the annualized rate of exacerbations ( @ vs. @ , P = @ ) and a reduction of @ points with respect to asthma symptoms ( P = @ ) , as measured on the Asthma Control Questionnaire @ ( in which the minimal clinically important difference is @ points ) .