title: Conversion from sirolimus to everolimus in kidney transplant recipients receiving a calcineurin-free regimen.
abstract: BACKGROUND
  Everolimus (EVL) and sirolimus (SRL) were introduced into immunosuppressive regimens, in an attempt to replace or reduce the dose of the nephrotoxic calcineurin inhibitors (CNI). In our institution, due to an administrative decision, conversion from SRL to EVL, was carried out, providing us the opportunity to investigate the effectiveness and safety profile of both drugs and to review the practical conversion dose between them.
  
  
  METHODS
  We retrospectively analyzed the medical records of 51 maintenance kidney transplant recipients receiving an SRL-based CNI-free regimen, who were switched to EVL. SRL dose was concentration controlled to a through level of 4-8 ng/mL. Patients were converted to a variable dose of EVL that was adjusted to achieve a trough concentration of 3-8 ng/mL.
  
  
  RESULTS
  SRL mean dose at time of conversion was 2.0 ± 0.9 mg/d. Initial EVL mean dose was 1.3 ± 0.5 mg/d. Six months after conversion, mean EVL trough level was 6.2 ± 2.8 ng/mL. EVL dose at this point was 2.0 ± 0.9 mg/d, which was not statistically different from SRL dose at the time of conversion (p = 0.575), suggesting a conversion factor of 1:1. During this six month period post conversion, no significant changes were observed in serum creatinine, hematocrit level, platelet count, proteinuria or lipid levels. No patient experienced an acute rejection episode.
  
  
  CONCLUSIONS
  Conversion from SRL to EVL in renal transplant recipients receiving a CNI-free immunosuppressive regimen can be performed safely with a low trough level range of EVL. We report for the first time a conversion factor between SRL and EVL.
authors: Nephrology Research and Development Unit, Faculty of Medicine, Hospital S. João, Porto, Portugal. catgcarvalho@gmail.com
authors: Catarina
authors: C
authors: Carvalho
authors: Luis
authors: L
authors: Coentrão
authors: Manuela
authors: M
authors: Bustorff
authors: Emilia
authors: E
authors: Patrício
authors: Susana
authors: S
authors: Sampaio
authors: Joana
authors: J
authors: Santos
authors: Gerardo
authors: G
authors: Oliveira
authors: Manuel
authors: M
authors: Pestana
mesh_terms: D019703:Calcineurin; D003404:Creatinine / Q000097:blood; D000068338:Everolimus; D005260:Female; D005919:Glomerular Filtration Rate; D006084:Graft Rejection / Q000188:drug therapy / Q000517:prevention & control*; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D020123:Sirolimus / Q000031:analogs & derivatives* / Q000627:therapeutic use*
chemical_list: D007166:Immunosuppressive Agents; D000068338:Everolimus; D003404:Creatinine; D019703:Calcineurin; D020123:Sirolimus