My biologic (Cosentyx) has been a game-changer for me. When my old biologic stopped working, it took three years for us to find another one that worked. Several times it got so bad, I literally couldn’t get out of bed. One time, I had to call a neighbor (who I barely knew) to help me out of bed. Super awkward.
Re: Sitting
I have found that rocking back and forth a little as I work is a big help. YMMV.