Combination preparation, containing cyclosporin a or FK506 or rapamycin and a xanthine derivative

Cyclosporin A (CysA) is a cyclic undecapeptide which is obtained from a fungus (CAS No.59865-13-3; U.S. Pat. No. 3,737,433). Its immunosuppressive effect has been known since 1972, but nevertheless it still took about 10 years until CysA found its way into the treatment of the acute rejection reaction of transplants (Borel J. F.: Cyclosporine. In: Dale M., Foreman J. C., Fan T. P. D. (eds.): Textbook of Immunology (3rd ed.). Blackwell Scient. Publ. Oxford 1994 pp 320-329). Today, as a result of its outstanding properties, CysA can no longer be overlooked in immunosuppression, even if its use is accompanied by a number of sometimes serious side effects. Xanthines of the formula I are useful in producing a superadditive increase in immunosuppressive action when combined with immunosuppressive compounds such as CysA or FK506.