How would you approach management of a patient with longstanding history of SLE, but having active psoriasis?

1. Since methotrexate (MTX) worked well before, I'd revisit other possible ways to use it in ways that minimize GI issues. For example, splitting up oral MTX over 24 hours can help alleviate GI side effects (eg 2.5 mg q 12 hours for 3 doses), yet have greater efficacy due to a larger area under the curve (concentration-wise). Or try low-dose SQ MTX.
2. I'd work closely with an excellent medical dermatologist. Could a lower dose of hydroxychloroquine (HCQ) possibly be considered (to get some efficacy for SLE and perhaps less chances for psoriasis exacerbation)? Though I use oral desensitization for HCQ hypersensitivity dermatitis, could desensitization also be used in this situation? Then use a maintenance dose lower than the dose that exacerbate...

In addition to above, I would consider deucravicitinib. It has PASI75 scores that are in the 60s, and is in trials for SLE. Its phase 2 trials seemed promising. Other PO JAK inhibitors should be efficacious but may carry worse side effect profile.

I have also employed PDE4 inhibitors such as po apremilast or roflumilast with modest improvements in psoriasis and cutaneous lupus.

I agree with @Dr. First Last, Sotyktu is likely to help with both disease processes. I would also add that Rinvoq being approved for PsA and also having been used off label for cutaneous lupus has worked very well in my hands and with a cleaner safety profile than methotrexate. When I worked with Dr. @Dr. First Last at Upenn, we also did put a few similar patients on Xeljanz who ended up doing well.