If she has it in her mind that making this trip to participate in the trials might cure her, there is very little that you can do to change her mind or to stop her. The only thing that I can suggest is that you could possibly advise her to educate herself thoroughly about Lupus, its treatments, its symptoms, and its medications before she makes that journey or makes a final decision. Short of that, it is not good for you to stress yourself about this issue as you are virtually powerless to do anything about it. You can only pray that this does not turn out badly for her and offer to be here for her no matter which way it turns out. I wish you the best.
Peace and Blessings
Look For The Good and Praise It!