According to our center standard, upon diagnosis of late AMR, all recipients (both study groups) on therapy with a calcineurin inhibitor (Tacrolimus or Cyclosporine A) or a mammalian Target of Rapamycin (mTOR) inhibitor (Everolimus or Sirolimus), without Azathioprine or MMF, will receive MMF (initially 2 x 500 mg per day; in absence of gastrointestinal side effects and significant leukopenia or thrombocytopenia stepwise increase of dose to 2 x 1000 mg per day) to avoid underimmunosuppression. Recipients weaned off steroids will receive low dose Prednisolone (initiation with 10 mg/day, tapered to 5 mg/day within 4 weeks).