Based on what you guys describe (shingles reactivation, mouth sore reactivation), I wonder if xeljanz is a stronger immunosuppressor than biologics are. And maybe that is why it is successful where the biologics had failed.
There is something called a bispecific antibody and it is essentially two monoclonal antibodies joined together so it targets two different receptors. They have been used for a long time in cancer and I saw a paper mentioning them for IBD but they haven’t been trialed yet. The danger would be really strong immunosuppression, or the two pathways interacting unexpectedly. But I think that is where the future is moving.