Custom session variable for filtered memberOf AD attribute

You can use a Variable Assign box with an expression like this:

set list "|";
foreach element [split [mcget {session.ad./Common/myPolicy_act_active_directory_query_ag.attr.member}] "|"] {
if { $element contains "Adm"}{
append list "$element | ";
}
}
return $list;

I assigned it to a variable session.custom.myvar. You will need to modify your session variable accordingly but it should work.