title: A multicenter experience with generic tacrolimus conversion.
abstract: BACKGROUND
  The first generic tacrolimus product gained Food and Drug Administration approval in August 2009. This prospective, observational trial sought to determine the need for dose titrations and measure drug cost savings on conversion to generic tacrolimus.
  
  
  METHODS
  Transplant recipients on stable tacrolimus doses were converted from brand to generic tacrolimus on a mg:mg basis. Data were collected at the time of generic conversion (study arm) and at a time point exactly 6 months before conversion (control arm) for all subjects.
  
  
  RESULTS
  Seventy conversions from four centers are reported. Subjects were a mean of 70 months after kidney (n=37), liver (n=28), or multiorgan (n=5) transplant. In the study arm, mean tacrolimus doses were 4.4 and 4.5 mg/d and mean tacrolimus trough concentrations were 5.8 and 5.9 ng/mL before and after conversion, respectively. In the control arm, mean tacrolimus doses were 4.6 and 4.6 mg/d and mean tacrolimus trough concentrations were 6.1 and 5.9 ng/mL before and after the control time point, respectively. Dose titrations occurred in five patients (7%) in the control arm and 15 patients (21%) in the study arm (P=0.028). Mean monthly drug costs were $645 for brand, $593 for generic, and $595 for generic after dose titrations. Mean monthly patient copays were $38 for brand and $15 for generic.
  
  
  CONCLUSIONS
  These cumulative data show that dose requirements and trough levels are similar between brand and generic tacrolimus and that generic substitution allows for savings. However, postconversion monitoring is prudent as patients may require dose titration.
authors.affiliation: Department of Pharmacy and Division of Transplant Surgery, Tufts Medical Center, Boston, MA 02111, USA. lmcdevitt@tuftsmedicalcenter.org
authors.forename: Lisa M
authors.initials: LM
authors.lastname: McDevitt-Potter
authors.forename: Basma
authors.initials: B
authors.lastname: Sadaka
authors.forename: Eric M
authors.initials: EM
authors.lastname: Tichy
authors.forename: Christin C
authors.initials: CC
authors.lastname: Rogers
authors.forename: Steven
authors.initials: S
authors.lastname: Gabardi
mesh_terms: D019540:Area Under Curve; D016527:Drug Costs; D057915:Drug Substitution; D016568:Drugs, Generic; D005260:Female; D006801:Humans; D007165:Immunosuppression Therapy / Q000191:economics* / Q000379:methods; D007166:Immunosuppressive Agents / Q000191:economics* / Q000627:therapeutic use*; D016030:Kidney Transplantation / Q000379:methods; D016031:Liver Transplantation / Q000379:methods; D008297:Male; D016377:Organ Transplantation / Q000379:methods*; D011446:Prospective Studies; D012306:Risk; D016559:Tacrolimus / Q000191:economics* / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D016568:Drugs, Generic; D007166:Immunosuppressive Agents; D016559:Tacrolimus