title: C2 monitoring of cyclosporine in stable renal transplant patients results in lower costs and improved renal function.
abstract: BACKGROUND
  C2 (2-hour post-absorption levels) monitoring of cyclosporine (CsA) seems to reduce the rate of acute rejection episodes (ARE) without increasing nephrotoxicity during the first months after transplant. There are a few reports on the impact of adopting this strategy in patients with stable renal transplants. We herein report a prospective trial in long-term renal transplant patients (>6 months) monitored by C0 or C3 who were switched to C2 monitoring.
  
  
  METHODS
  Seventy-six (mean age = 43 +/- 11 years) kidney transplant patients (mean = 37 +/- 21 months after transplant) receiving CsA, steroids, and azathioprine were switched to C2 monitoring, seeking to achieve a target range of 800 +/- 100 ng/mL. The patients were followed for at least 6 months.
  
  
  RESULTS
  At conversion the C2 values of 61% of the patients were above and 17% below the therapeutic range. Six months after conversion there was a significant reduction in BUN (29 +/- 11 vs 27 +/- 10, P < .01), Creatinine (Cr), cholesterol, and triglyceride levels were unchanged. Mean CsA dose was decreased 10% from 244 +/- 63 to 220 +/- 52 (P < .01), implying a net savings of 390 US dollars per patient per year. Among the group of patients who showed a high C2 level, there was also a reduction in BUN (30 +/- 12 vs 27 +/- 10, P < .01) and a nonsignificant decrease in Cr (1.53 +/- 0.6 vs 1.50 +/- 0.6).
  
  
  CONCLUSIONS
  C2 monitoring in stable kidney transplant recipients is feasible and safe. The strategy results in reduced drug costs and improved renal function.
authors.affiliation: Department of Urology, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile. javierdomi@hotmail.com
authors.forename: J
authors.initials: J
authors.lastname: Domínguez
authors.forename: D
authors.initials: D
authors.lastname: Fuenzalida
authors.forename: R
authors.initials: R
authors.lastname: Norambuena
authors.forename: E
authors.initials: E
authors.lastname: Pais
authors.forename: G
authors.initials: G
authors.lastname: Cortes Monroy
authors.forename: R
authors.initials: R
authors.lastname: Llanos
mesh_terms: D000328:Adult; D001806:Blood Urea Nitrogen; D002677:Chile; D003365:Costs and Cost Analysis; D003404:Creatinine / Q000097:blood; D016572:Cyclosporine / Q000191:economics / Q000493:pharmacokinetics / Q000627:therapeutic use*; D016903:Drug Monitoring / Q000379:methods; D005260:Female; D006400:Hematocrit; D006801:Humans; D007166:Immunosuppressive Agents / Q000191:economics / Q000493:pharmacokinetics / Q000627:therapeutic use*; D007677:Kidney Function Tests; D016030:Kidney Transplantation / Q000276:immunology / Q000502:physiology*; D050356:Lipid Metabolism; D008297:Male; D008657:Metabolic Clearance Rate; D013997:Time Factors
chemical_list: D007166:Immunosuppressive Agents; D016572:Cyclosporine; D003404:Creatinine