Six hyperimmunized patients awaiting a kidney graft underwent immunoadsorption of separated plasma through a protein-A column to remove HLA antibodies. This procedure was partially limited by constant and rapid antibody resynthesis in spite of strong immunosuppression with cyclophosphamide and prednisolone. Only two patients could be grafted with previously positive--currently negative crossmatches. The first died of infection on day 40, having developed early chronic vascular rejection and the other returned to hemodialysis on day 285 after the development of transplant glomerulopathy. However, immunoadsorption seems to be effective in removing HLA antibodies having a titer below 1/2. Such extremely hyperimmunized patients should probably be excluded from the immunoadsorption program.