The median CD4 % value rose from 10 % to 23 % at 12 weeks and to 24.5 % at 24 weeks in the zinc group , whereas in the placebo group , the value rose from 11 % to 20 % at 12 weeks and to 22 % at 24 weeks ( P = 0.188 for comparison between the zinc and the placebo group at 12 wk and P = 0.3 for comparison at 24 wk ) .