We've had at least 2 members in the past who tried Benlysta. Unfortunately they were both extremely ill and moved on to IVIG and still had extensive complications.
We don't seem to have any currently active members, sorry. You may try the websites
https://www.lupus.org,
https://www.lupusresearch.org or other lupus organizations to see if they have more active Lupus Forums. I'd search for "Lupus Forums"