What do you use to treat a kidney transplant patient with progressive BK nephropathy despite a maximal decrease in immunosuppression for months?

Assuming you are referring to actual BK nephropathy (biopsy evidence of viral inclusion on renal tubular cells staining positive by SV40 either by IF or immunohistochemistry) + serum BK viral PCR.

Beyond lowering immunosuppression, adjunctive therapy (none of which are FDA approved of course) includ...