Bioreductive drugs: from concept to clinic

Stephanie McKeown, RL Cowen, KJ Williams

    Research output: Contribution to journalArticle

    130 Citations (Scopus)

    Abstract

    One of the key issues for radiobiologists is the importance of hypoxia to the radiotherapy response. This review addresses the reasons for this and primarily focuses on one aspect, the development of bioreductive drugs that are specifically designed to target hypoxic tumour cells. Four classes of compound have been developed since this concept was first proposed: quinones, nitroaromatics, aliphatic and heteroaromatic N-oxides. All share two characteristics: (1) they require hypoxia for activation and (2) this activation is dependent on the presence of specific reductases. The most effective compounds have shown the ability to enhance the anti-tumour efficacy of agents that kill better-oxygenated cells, i.e. radiation and standard cytotoxic chemotherapy agents such as cisplatin and cyclophosphamide. Tirapazamine (TPZ) is the most widely studied of the lead compounds. After successful pre-clinical in vivo combination studies it entered clinical trial; over 20 trials have now been reported. Although TPZ has enhanced some standard regimens, the results are variable and in some combinations toxicity was enhanced. Banoxantrone (AQ4N) is another agent that is showing promise in early phase I/II clinical trials; the drug is well tolerated, is known to locate in the tumour and can be given in high doses without major toxicities. Mitomycin C (MMC), which shows some bioreductive activation in vitro, has been tested in combination trials. However, it is difficult to assign the enhancement of its effects to targeting of the hypoxic cells because of the significant level of its hypoxia-independent toxicity. More specific analogues of MMC, e.g. porfiromycin and apaziquone (E09), have had variable success in the clinic. Other new drugs that have good pre-clinicai profiles are PR 104 and NLCQ-1; data on their clinical safety/efficacy are not yet available. This paper reviews the pre-clinical data and discusses the clinical studies that have been reported.
    LanguageEnglish
    Pages427-442
    JournalClinical Oncology
    Volume19
    Issue number6
    DOIs
    Publication statusPublished - Aug 2007

    Fingerprint

    tirapazamine
    apaziquone
    Mitomycin
    Porfiromycin
    Pharmaceutical Preparations
    Neoplasms
    Quinones
    Phase II Clinical Trials
    Clinical Trials, Phase I
    Cytotoxins
    Cyclophosphamide
    Oxides
    Cisplatin
    Oxidoreductases
    Radiotherapy
    Clinical Trials
    Radiation
    Safety
    Drug Therapy
    Hypoxia

    Cite this

    McKeown, S., Cowen, RL., & Williams, KJ. (2007). Bioreductive drugs: from concept to clinic. 19(6), 427-442. https://doi.org/10.1016/j.clon.2007.03.006
    McKeown, Stephanie ; Cowen, RL ; Williams, KJ. / Bioreductive drugs: from concept to clinic. 2007 ; Vol. 19, No. 6. pp. 427-442.
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    McKeown, S, Cowen, RL & Williams, KJ 2007, 'Bioreductive drugs: from concept to clinic', vol. 19, no. 6, pp. 427-442. https://doi.org/10.1016/j.clon.2007.03.006

    Bioreductive drugs: from concept to clinic. / McKeown, Stephanie; Cowen, RL; Williams, KJ.

    Vol. 19, No. 6, 08.2007, p. 427-442.

    Research output: Contribution to journalArticle

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    McKeown S, Cowen RL, Williams KJ. Bioreductive drugs: from concept to clinic. 2007 Aug;19(6):427-442. https://doi.org/10.1016/j.clon.2007.03.006