Cancer Chemotherapy and Pharmacology

, Volume 67, Issue 5, pp 1145–1155 | Cite as

A combined pharmacokinetic model for the hypoxia-targeted prodrug PR-104A in humans, dogs, rats and mice predicts species differences in clearance and toxicity

  • Kashyap Patel
  • Steve S. F. Choy
  • Kevin O. Hicks
  • Teresa J. Melink
  • Nicholas H. G. Holford
  • William R. WilsonEmail author
Original Article



PR-104 is a phosphate ester that is systemically converted to the corresponding alcohol PR-104A. The latter is activated by nitroreduction in tumours to cytotoxic DNA cross-linking metabolites. Here, we report a population pharmacokinetic (PK) model for PR-104 and PR-104A in non-human species and in humans.


A compartmental model was used to fit plasma PR-104 and PR-104A concentration–time data after intravenous (i.v.) dosing of humans, Beagle dogs, Sprague–Dawley rats and CD-1 nude mice. Intraperitoneal (i.p.) PR-104 and i.v. PR-104A dosing of mice was also investigated. Protein binding was measured in plasma from each species. Unbound drug clearances and volumes were scaled allometrically.


A two-compartment model described the disposition of PR-104 and PR-104A in all four species. PR-104 was cleared rapidly by first-order (mice, rats, dogs) or mixed-order (humans) metabolism to PR-104A in the central compartment. The estimated unbound human clearance of PR104A was 211 L/h/70 kg, with a steady state unbound volume of 105 L/70 kg. The size equivalent unbound PR-104A clearance was 2.5 times faster in dogs, 0.78 times slower in rats and 0.63 times slower in mice, which may reflect reported species differences in PR-104A O-glucuronidation.


The PK model demonstrates faster size equivalent clearance of PR-104A in dogs and humans than rodents. Dose-limiting myelotoxicity restricts the exposure of PR-104A in humans to approximately 25% of that achievable in mice.


Hypoxia-activated prodrugs Nitrogen mustards Pharmacokinetics PR-104 Allometry 



We thank Proacta Inc. for provision of PR-104 and access to pharmacokinetic and toxicity data for rats, dogs and humans, and MicroConstants Inc. for assay of PR-104 and PR-104A in plasma from these species. The study was supported by grant 08/103 from the Health Research Council of New Zealand and a Fellowship to KP from the Auckland Medical Research Foundation.

William R. Wilson is a founding scientist, stockholder and consultant to Proacta, Inc.

Supplementary material

280_2010_1412_MOESM1_ESM.doc (148 kb)
Supplementary material 1 (DOC 133 kb)


  1. 1.
    Carmeliet P (2005) Angiogenesis in life, disease and medicine. Nature 438:932–936PubMedCrossRefGoogle Scholar
  2. 2.
    Liao D, Johnson RS (2007) Hypoxia: a key regulator of angiogenesis in cancer. Cancer Metastasis Rev 26:281–290PubMedCrossRefGoogle Scholar
  3. 3.
    Kioi M, Vogel H, Schultz G, Hoffman RM, Harsh GR, Brown JM (2010) Inhibition of vasculogenesis, but not angiogenesis, prevents the recurrence of glioblastoma after irradiation in mice. J Clin Invest 120:694–705PubMedCrossRefGoogle Scholar
  4. 4.
    Erler JT, Giaccia AJ (2006) Lysyl oxidase mediates hypoxic control of metastasis. Cancer Res 66:10238–10241PubMedCrossRefGoogle Scholar
  5. 5.
    O’Donnell JL, Joyce MR, Shannon AM, Harmey J, Geraghty J, Bouchier-Hayes D (2006) Oncological implications of hypoxia inducible factor-1alpha (HIF-1alpha) expression. Cancer Treat Rev 32:407–416PubMedCrossRefGoogle Scholar
  6. 6.
    Bristow RG, Hill RP (2008) Hypoxia, DNA repair and genetic instability. Nat Rev Cancer 8:180–192PubMedCrossRefGoogle Scholar
  7. 7.
    Gatenby RA, Gillies RJ (2007) Glycolysis in cancer: a potential target for therapy. Int J Biochem Cell Bio 39:1358–1366CrossRefGoogle Scholar
  8. 8.
    Koong AC, Chauhan V, Romero-Ramirez L (2006) Targeting XBP-1 as a novel anti-cancer strategy. Cancer Biol Ther 5:756–759PubMedCrossRefGoogle Scholar
  9. 9.
    Graeber TG, Osmanian C, Jacks T, Housman DE, Koch CJ, Lowe SW, Giaccia AJ (1996) Hypoxia-mediated selection of cells with diminished apoptotic potential in solid tumours. Nature 379:88–91PubMedCrossRefGoogle Scholar
  10. 10.
    Brown JM, Wilson WR (2004) Exploiting tumor hypoxia in cancer treatment. Nat Rev Cancer 4:437–447PubMedCrossRefGoogle Scholar
  11. 11.
    Tatum JL, Kelloff GJ, Gillies RJ, Arbeit JM, Brown JM, Chao KS, Chapman JD, Eckelman WC, Fyles AW, Giaccia AJ, Hill RP, Koch CJ, Krishna MC, Krohn KA, Lewis JS, Mason RP, Melillo G, Padhani AR, Powis G, Rajendran JG, Reba R, Robinson SP, Semenza GL, Swartz HM, Vaupel P, Yang D, Croft B, Hoffman J, Liu G, Stone H, Sullivan D (2006) Hypoxia: importance in tumor biology, noninvasive measurement by imaging, and value of its measurement in the management of cancer therapy. Int J Radiat Biol 82:699–757PubMedCrossRefGoogle Scholar
  12. 12.
    Stratford IJ, Workman P (1998) Bioreductive drugs into the next millennium. Anticancer Drug Des 13:519–528PubMedGoogle Scholar
  13. 13.
    Denny WA (2001) Prodrug strategies in cancer therapy. Eur J Med Chem 36:577–595PubMedCrossRefGoogle Scholar
  14. 14.
    Wardman P (2001) Electron transfer and oxidative stress as key factors in the design of drugs selectively active in hypoxia. Curr Med Chem 8:739–761PubMedGoogle Scholar
  15. 15.
    McKeown SR, Cowen RL, Williams KJ (2007) Bioreductive drugs: from concept to clinic. Clin Oncol 19:427–442CrossRefGoogle Scholar
  16. 16.
    Chen Y, Hu L (2009) Design of anticancer prodrugs for reductive activation. Med Res Rev 29:29–64PubMedCrossRefGoogle Scholar
  17. 17.
    Jameson MB, Rischin D, Pegram M, Gutheil J, Patterson AV, Denny WA, Wilson WR (2010) A phase I pharmacokinetic trial of PR-104, a nitrogen mustard prodrug activated by both hypoxia and aldo-keto reductase 1C3, in patients with solid tumors. Cancer Chemother Pharmacol 65:791–801PubMedCrossRefGoogle Scholar
  18. 18.
    Patterson AV, Ferry DM, Edmunds SJ, Gu Y, Singleton RS, Patel K, Pullen SM, Syddall SP, Atwell GJ, Yang S, Denny WA, Wilson WR (2007) Mechanism of action and preclinical antitumor activity of the novel hypoxia-activated DNA crosslinking agent PR-104. Clin Cancer Res 13:3922–3932PubMedCrossRefGoogle Scholar
  19. 19.
    Singleton RS, Guise CP, Ferry DM, Pullen SM, Dorie MJ, Brown JM, Patterson AV, Wilson WR (2009) DNA crosslinks in human tumor cells exposed to the prodrug PR-104A: relationships to hypoxia, bioreductive metabolism and cytotoxicity. Cancer Res 69:3884–3891PubMedCrossRefGoogle Scholar
  20. 20.
    Guise CP, Wang A, Thiel A, Bridewell D, Wilson WR, Patterson AV (2007) Identification of human reductases that activate the dinitrobenzamide mustard prodrug PR-104A: a role for NADPH:cytochrome P450 oxidoreductase under hypoxia. Biochem Pharmacol 74:810–820PubMedCrossRefGoogle Scholar
  21. 21.
    Guise CP, Abbattista M, Singleton RS, Holford SD, Connolly J, Dachs GU, Fox SB, Pollock R, Harvey J, Guilford P, Doñate F, Wilson WR, Patterson AV (2010) The bioreductive prodrug PR-104A is activated under aerobic conditions by human aldo-keto reductase 1C3. Cancer Res 70:1573–1584PubMedCrossRefGoogle Scholar
  22. 22.
    Hicks KO, Myint H, Patterson AV, Pruijn FB, Siim BG, Patel K, Wilson WR (2007) Oxygen dependence and extravascular transport of hypoxia-activated prodrugs: comparison of the dinitrobenzamide mustard PR-104A and tirapazamine. Int J Radiat Oncol Biol Phys 69:560–571PubMedCrossRefGoogle Scholar
  23. 23.
    Wilson WR, Hicks KO, Pullen SM, Ferry DM, Helsby NA, Patterson AV (2007) Bystander effects of bioreductive drugs: potential for exploiting pathological tumor hypoxia with dinitrobenzamide mustards. Radiat Res 167:625–636PubMedCrossRefGoogle Scholar
  24. 24.
    Liu SC, Ahn GO, Kioi M, Dorie MJ, Patterson AV, Brown JM (2008) Optimised Clostridium-directed enzyme prodrug therapy improves the antitumor activity of the novel DNA crosslinking agent PR-104. Cancer Res 68:7995–8003PubMedCrossRefGoogle Scholar
  25. 25.
    Patel K, Lewiston D, Gu Y, Hicks KO, Wilson WR (2007) Analysis of the hypoxia-activated dinitrobenzamide mustard phosphate prodrug PR-104 and its alcohol metabolite PR-104A in plasma and tissues by liquid chromatography-mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 856:302–311PubMedCrossRefGoogle Scholar
  26. 26.
    Gu Y, Wilson WR (2009) Rapid and sensitive ultra-high-pressure liquid chromatography-tandem mass spectrometry analysis of the novel anticancer agent PR-104 and its major metabolites in human plasma: application to a pharmacokinetic study. J Chromatogr B Analyt Technol Biomed Life Sci 877:3181–3186PubMedCrossRefGoogle Scholar
  27. 27.
    Jameson MB, McKeage MJ, Ramanathan RK, Rajendran J, Gu Y, Wilson WR, Melink TJ, Tchekmedyian NS (2010) Final results of a phase Ib trial of PR-104, a pre-prodrug of the bioreductive prodrug PR-104A, in combination with gemcitabine or docetaxel in patients with advanced solid tumors. ASCO Meeting Abstracts (Abstract 2554)Google Scholar
  28. 28.
    Anderson BJ, Holford NHG (2008) Mechanism-based concepts of size and maturity in pharmacokinetics. Ann Rev Pharmacol Toxicol 48:303–332CrossRefGoogle Scholar
  29. 29.
    Denny WA, Atwell GJ, Yang S, Wilson WR, Patterson AV, Helsby NA (2005) Novel nitrophenyl mustard and nitrophenylaziridine alcohols and their corresponding phosphates and their use as targeted cytotoxic agents. PCT WO2005042471A1Google Scholar
  30. 30.
    Holford NHG (1996) A size standard for pharmacokinetics. Clin Pharmacokinet 30:329–332PubMedCrossRefGoogle Scholar
  31. 31.
    West GB, Brown JH, Enquist BJ (1997) A general model for the origin of allometric scaling laws in biology. Science 279:122–126CrossRefGoogle Scholar
  32. 32.
    West GB, Brown JH, Enquist BJ (1999) The fourth dimension of life: fractal geometry and allometric scaling of organisms. Science 284:1677–1679PubMedCrossRefGoogle Scholar
  33. 33.
    Anderson BJ, Woollard GA, Holford NHG (2000) A model for size and age changes in the pharmacokinetics of paracetamol in neonates, infants and children. Br J Clin Pharmacol 502:125–134CrossRefGoogle Scholar
  34. 34.
    Kolokotrones T, Savage V, Deeds EJ, Fontana W (2010) Curvature in metabolic scaling. Nature 464:753–756PubMedCrossRefGoogle Scholar
  35. 35.
    Gu Y, Atwell GJ, Wilson WR (2010) Metabolism and excretion of the novel bioreductive prodrug PR-104 in mice, rats, dogs and humans. Drug Metab Dispos 38:498–508PubMedCrossRefGoogle Scholar
  36. 36.
    Gu Y, Guise CP, Patel K, Abbattista MR, Lie J, Sun X, Atwell GJ, Boyd M, Patterson AV, Wilson WR (2010) Reductive metabolism of the dinitrobenzamide mustard anticancer prodrug PR-104 in mice. Cancer Chemother Pharmacol. doi: 10.1007/s00280-010-1354-5 Google Scholar
  37. 37.
    Velica P, Davies NJ, Rocha PP, Schrewe H, Ride JP, Bunce CM (2009) Lack of functional and expression homology between human and mouse aldo-keto reductase 1C enzymes: implications for modelling human cancers. Mol Cancer 8:121–132PubMedCrossRefGoogle Scholar
  38. 38.
    Birtwistle J, Hayden RE, Khanim FL, Green RM, Pearce C, Davies NJ, Wake N, Schrewe H, Ride JP, Chipman JK, Bunce CM (2009) The aldo-keto reductase AKR1C3 contributes to 7, 12-dimethylbenz(a)anthracene-3, 4-dihydrodiol mediated oxidative DNA damage in myeloid cells: implications for leukemogenesis. Mutat Res 662:67–74PubMedGoogle Scholar
  39. 39.
    Peterson JK, Houghton PJ (2004) Integrating pharmacology and in vivo cancer models in preclinical and clinical drug development. Eur J Cancer 40:837–844PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Kashyap Patel
    • 1
  • Steve S. F. Choy
    • 2
  • Kevin O. Hicks
    • 1
  • Teresa J. Melink
    • 3
  • Nicholas H. G. Holford
    • 2
  • William R. Wilson
    • 1
    Email author
  1. 1.Faculty of Medical and Health SciencesAuckland Cancer Society Research Centre, The University of AucklandAucklandNew Zealand
  2. 2.Department of Pharmacology and Clinical Pharmacology, Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand
  3. 3.Proacta Inc. 9255 Towne Centre DriveSan DiegoUSA

Personalised recommendations