The Determination of Metabolite M 17 and Its Meaning for Immunosuppressive Cyclosporin Therapy

Abstract

Cyclosporin A (CyA) is intensively metabolized by the hepatic cytochrome p450 III monooxygenase A system in the human liver, the most important metabolites being M1, M17, and M21. Because CyA and its metabolites have nephrotoxic, hepatotoxic, and neurotoxic side effects, CyA dosage must be calculated to avoid the risk of organ rejection through underdosage and toxic organ damage through overdosage or accumulation of metabolites.

In this study, we determined the whole-blood concentrations of cyclosporin and metabolite M17 by high-pressure liquid chromatography (HPLC) and by monoclonal specific and polyclonal nonspecific fluorescence polarization immunoassay (Abbott) in patients after immunosuppressive treatment.

Patients with different resorption and metabolization rates showed high individual variations. CyA concentrations in patients with good liver function and low concentra tions of CyA metabolites showed a good correlation between the HPLC and the FPIA (TDx-monoclonal assay) methods in ranges between 25 and 180 ng/mL. TDx-mono clonal was not always as precise as HPLC. In cases of metabolic disorders, we found false high CyA concentrations assayed with the immunologic method, caused by a cross- reaction of the elevated metabolite concentration. We found that HPLC rendered more information about the extent of immunosuppressive activity and the metabolization rate and showed a good correlation with the concentration of metabolite M17 and total metabolites measured with the Abbott CyA polyclonal kit.

Get full access to this article

View all access options for this article.

References

Lermaire M. , Fahr A. , Maurer G. : Pharmacokinetics of cyclosporin: Inter- and intra-individual variations and metabolic pathways. Transplant Proc 22:1110-1112, 1990.

Van Buren D. , Widemann CA , Ried M. , et al: The antagonistic effect of rifampin upon cyclosporin bioavailability. Transplant Proc 16:1642-1645, 1984.

Christians U. , Sewing KF : Cyclosporin metabolism in transplant patients . Pharmacol Ther 57:291-345, 1993.

Maurer G. , Lemaire M. : Biotransformation and distribution in blood of cyclosporin and its metabolites . Transplant Proc 18:25-34, 1986.

Wallemacq PE , Lhoest G. , Dumont P. : Isolation, purification and structure elucidation of cyclosporin metabolites in rabbit and man. Biomed Environ Mass Spectrom 18:48-56, 1989.

Brockmüller UJ , Jochimsen F. , Keller F. , et al: Cyclosporin metabolites and central nervous system toxicity. Lancet I:1223, 1988.

Davenport A. , Wiil EJ , Davison AM , et al: Toxicity of cyclosporin metabolites . Lancet II:333, 1988.

Kohlhaw K. , Wonigeit K. , Schafer O. , et al: Association of very high blood levels of cyclosporin metabolites with clinical complications after liver transplantation. Transplant Proc 21:2232-2233, 1989.

Leunissen K. , Baumann G. , Bosman R. , et al: Cyclosporin metabolites and nephrotoxicity . Lancet II:1398, 1986.

10.

Wysocki GP , Gebhardt W. , Kopsa H. , et al: Fibrous hyperplasia of the gingiva: A side effect of cyclosporin A therapy. Oral Surg 55:274-278, 1983.

11.

Schmidt JB , Gebhardt W. , Kopsa H. , et al: Does cyclosporin A influence sex hormone levels? Exp Clin Endocr 88:207-211, 1986.

12.

Penn I. , Brunson ME : Cancer after cyclosporin therapy. Transplant Proc 20:885-892, 1988.

13.

Sewing KF , Christians U. , Kohlhaw K. , et al: Biological activity of cyclosporin metabolites. Transplant Proc 22:1129-1139, 1990.

14.

Freed BM , Rosano TG , Lempert N. : In vitro immunosuppressive properties of cyclosporin metabolites. Transplantation 43:123-127, 1986.

15.

Khoschsorur G. , Semmelrock HJ , Rödl S. , et al: Rapid, sensitive high-performance liquid chromatographic method for the determination of CyA and its metabolites M1, M17 and M21. J Chromatography 690:367-372, 1997.

16.

Nattermann U. , Steiner W. , Land W. : Vergleich der Klinischen Wertigkeit eines polyspezifischen und eines monospezifischen Assays zur postoperativen Ciclosporin-Bestimmung nach Nierentrans-plantation. Z Transplantationsmedizin, Sonderdruck, Nr. 4, 1990.

17.

Rossano TG , Freed BM , Gerilli J. , et al: Immunosuppressive metabolites of cyclosporin in the blood of renal allograft recipients. Transplantation 42:262, 1986.

18.

Freed BM , Stevens C. , Brooks C. , et al: Assessment of the biological activity of cyclosporin metabolites using the human jurkat cell line. Transplant Proc 23: 980, 1991.

19.

Kunzendorf U. , Brockmöller J. , Jochimsen F. , et al: Immunosuppressive properties of cyclosporin metabolites. Lancet 1:734, 1989.

20.

Moyer TP , Winkels J. , Krom R. , et al: Evalution of Abbott TDx monoclonal assay of cyclosporin in whole blood. Clin Chem 37:16-20, 1991.

21.

Wang P. , Meucci V. , Simpson E. , et al: A monoclonal antibody fluorescent polarization immunoassay for cyclosporin. Transplant Proc 22:1186-1188, 1990.

22.

Tredger JM , Gonde CE , Williams R. : Monitoring cyclosporin in liver-transplant recipients: Effects of clinical status on the performance of two monoclonal antibody-based methods. Clin Chem 38:108-113, 1992.

23.

Lucey MR , Kolars JC , Merion RM , et al: Cyclosporin toxicity at therapeutic blood levels and cytochrome P450IIIA. Lancet 335:11-15, 1990.

24.

Burckart GJ , Venkataramanan R. , Ptachcinski RJ , et al: Cyclosporin pharmacokinetic profiles in liver, heart and kidney transplant patients as determined by HPLC. Transplant Proc 18:457-476, 1986.