Orencia takes a long time when it works the way it is intended. Basically you will stop making so many Helper T cells because of the blocked education by APCs. It will take a long time for existing ones targeted to your RA causative proteins to die even if new ones aren't being made so quickly. Those Helper Ts, are being used to induce clonal expansion of B cells that are producing Abs which are most likely the effector of the disease. One of these Th cells can turn on many B cells. So the eventual reduction of these B cells is also going to take additional months. Finally, you have to wait for the antibodies produced by these Bcells to leave circulation. That has a half-life of about 20 days. So lets say another month.
There is an immediate affect experienced by some people, but this is a different mechanism where the APCs themselves are suppressed by Orencia and not common. Don't listen to the circus. It is supposed to take time, though I would guess about 3 months.