title: Characterization of renal biomarkers for use in clinical trials: effect of preanalytical processing and qualification using samples from subjects with diabetes.
abstract: BACKGROUND
  Identifying the potential for drug-induced kidney injury is essential for the successful research and development of new drugs. Newer and more sensitive preclinical drug-induced kidney injury biomarkers are now qualified for use in rat toxicology studies, but biomarkers for clinical studies are still undergoing qualification. The current studies investigated biomarkers in healthy volunteer (HV) urine samples with and without the addition of stabilizer as well as in urine from patients with normoalbuminuric diabetes mellitus (P-DM).
  
  
  METHODS
  Urine samples from 20 male HV with stabilizer, 69 male HV without stabilizer, and 95 male DM without stabilizer (39 type 1 and 56 type 2) were analyzed for the following bio-markers using multiplex assays: α-1-microglobulin (A1M), β-2-microglobulin, calbindin, clusterin, connective tissue growth factor (CTGF), creatinine, cystatin-C, glutathione S-transferase α (GSTα), kidney injury marker-1 (KIM-1), microalbumin, neutrophil gelatinase-associated lipocalin, osteopontin, Tamm-Horsfall urinary glycoprotein (THP), tissue inhibitor of metalloproteinase 1, trefoil factor 3 (TFF3), and vascular endothelial growth factor.
  
  
  RESULTS
  CTGF and GSTα assays on nonstabilized urine were deemed nonoptimal (>50% of values below assay lower limits of quantification). "Expected values" were determined for HV with stabilizer, HV without stabilizer, and P-DM without stabilizer. There was a statistically significant difference between HV with stabilizer compared to HV without stabilizer for A1M, CTGF, GSTα, and THP. DM urine samples differed from HV (without stabilizer) for A1M CTGF, GSTα, KIM-1, microalbumin, osteopontin, and TFF3. A1M also correctly identified HV and DM with an accuracy of 89.0%.
  
  
  CONCLUSIONS
  These studies: 1) determined that nonstabilized urine can be used for assays under qualification; and 2) documented that A1M, CTGF, GSTα, KIM-1, microalbumin, osteopontin, and TFF3 were significantly increased in urine from P-DM. In addition, the 89.0% accuracy of A1M in distinguishing P-DM from HV may allow this biomarker to be used to monitor efficacy of potential renal protective agents.
authors.affiliation: Enabling Safety Sciences, Wilmington, DE, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Brott
authors.affiliation: Enabling Safety Sciences, Wilmington, DE, USA.
authors.forename: Stephen T
authors.initials: ST
authors.lastname: Furlong
authors.affiliation: Enabling Safety Sciences, Wilmington, DE, USA.
authors.forename: Scott H
authors.initials: SH
authors.lastname: Adler
authors.affiliation: AstraZeneca Pharmaceuticals, Wilmington, DE, USA.
authors.forename: James W
authors.initials: JW
authors.lastname: Hainer
authors.affiliation: AstraZeneca Pharmaceuticals, Wilmington, DE, USA.
authors.forename: Ramin B
authors.initials: RB
authors.lastname: Arani
authors.affiliation: Drug Safety and Metabolism, AstraZeneca Pharmaceuticals, Alderley Park, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Pinches
authors.affiliation: Steno Diabetes Center, Gentofte, Denmark ; Aarhus University, Aarhus, Denmark ; University of Copenhagen, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Rossing
authors.affiliation: Institute of Cardiovascular Sciences, University College London, London, UK.
authors.forename: Nish
authors.initials: N
authors.lastname: Chaturvedi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002986:Clinical Trials as Topic / Q000379:methods*; D003922:Diabetes Mellitus, Type 1 / Q000175:diagnosis / Q000652:urine*; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis / Q000652:urine*; D003937:Diagnosis, Differential; D064368:Healthy Volunteers; D006801:Humans; D007668:Kidney / Q000187:drug effects / Q000378:metabolism*; D007674:Kidney Diseases / Q000139:chemically induced / Q000175:diagnosis / Q000652:urine*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012107:Research Design; D013048:Specimen Handling / Q000379:methods*; D016482:Urinalysis; D055815:Young Adult
keywords: drug development; healthy volunteers; kidney