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Anastrozole

A Review of its Use in the Management of Postmenopausal Women with Advanced Breast Cancer

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Abstract

Anastrozole is a new oral nonsteroidal aromatase inhibitor indicated for the second-line endocrine treatment of postmenopausal women with advanced breast cancer. In postmenopausal women, anastrozole significantly reduces plasma estrogen levels; maximal suppression is achieved at dosages ≥1 mg/day and levels remain suppressed during long term therapy.

In two phase III clinical trials, anastrozole 1 or 10 mg/day showed similar clinical efficacy to that of oral megestrol (megestrol acetate) 160 mg/day in postmenopausal women with advanced breast cancer. Primary end-points [including time to disease progression (120 to 170 days) and overall response rates (complete and partial response and stable disease lasting ≥24 weeks: 29 to 37%)] and secondary end-points [time to treatment failure (115 to 168 days) and duration of response (257 to 261 days)] did not differ significantly between treatment groups. However, a significant survival advantage was observed in patients treated with anastrozole 1 mg/day compared with megestrol in a follow-up combined analysis of patients enrolled in both studies (median time to death 26.7 vs 22.5 months). Quality of life parameters were generally improved to a similar extent in all treatment groups.

Anastrozole is generally well tolerated in the majority of patients, the most common adverse events being gastrointestinal (GI) disturbances (incidence 29 to 33%). These events are generally mild or moderate and transient. Other adverse events reported with anastrozole include headache (≤18%), asthenia (≤16%), pain (≤15%), hot flushes and bone pain (both ≤12%), back pain and dyspnoea (both ≤11%) and peripheral oedema (≤9%). GI disturbance tended to be more common with anastrozole than megestrol, particularly at the 10 mg/day dosage; however, compared with megestrol, anastrozole is less frequently associated with weight gain.

Conclusions: Anastrozole, with its apparent survival advantage versus megestrol (demonstrated in a combined analysis of phase III studies), convenient once daily oral administration and acceptable short term tolerability profile, is a second-line treatment option for postmenopausal patients with tamoxifenrefractory advanced breast cancer. The results of ongoing comparative trials with tamoxifen will determine the relative efficacy of anastrozole as first-line endocrine therapy for advanced breast cancer and as adjuvant therapy for early disease. In addition, direct comparative studies are required to determine the efficacy of anastrozole relative to that of other oral aromatase inhibitors such as letrozole and vorozole.

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References

  1. Jaiyesimi IA, Buzdar AU, Decker DA, et al. Use of tamoxifen for breast cancer: twenty-eight years later. J Clin Oncol 1995; 13(2): 513–29

    PubMed  CAS  Google Scholar 

  2. Buzdar AU, Hortobagyi G. Update on endocrine therapy for breast cancer. Clin Cancer Res 1998; 4: 527–34

    PubMed  CAS  Google Scholar 

  3. Goss PE, Gwyn KMEH. Current perspectives on aromatase inhibitors in breast cancer. J Clin Oncol 1994 Nov; 12: 2460–70

    PubMed  CAS  Google Scholar 

  4. Leonard RCF, Rodger A, Dixon JM. Metastatic breast cancer. BMJ 1994 Dec; 309: 1501–4

    Article  PubMed  CAS  Google Scholar 

  5. Dowsett M. Biological background to aromatase inhibition. Breast 1996; 5(3): 196–201

    Article  Google Scholar 

  6. Miller WR. Aromatase inhibitors and breast cancer. Cancer Treat Rev 1997; 23: 171–87

    Article  PubMed  CAS  Google Scholar 

  7. Coombes RC, Goss PE, Dowsett M, et al. 4-Hydroxyandrostenedione treatment for postmenopausal patients with advanced breast cancer. Steroids 1987 Jul–Sep; 50: 245–52

    Article  PubMed  CAS  Google Scholar 

  8. Harris AL, Powles TJ, Smith IE, et al. Aminoglutethimide for the treatment of advanced postmenopausal breast cancer. Eur J Cancer Clin Oncol 1983; 19: 11–7

    Article  PubMed  CAS  Google Scholar 

  9. Wiseman LR, Goa KL. Formestane: a review of its pharmacological properties and clinical efficacy in the treatment of postmenopausal breast cancer. Drugs Aging 1996 Oct; 9(4): 292–306

    Article  PubMed  CAS  Google Scholar 

  10. Plourde PV, Dyroff M, Dukes M. Arimidex®: a potent and selective fourth-generation aromatase inhibitor. Breast Cancer Res Treat 1994; 30(1): 103–11

    Article  PubMed  CAS  Google Scholar 

  11. Dukes M, Edwards PN, Large M, et al. The preclinical pharmacology of Arimidex (anastrozole; ZD1033): a potent, selective aromatase inhibitor. J Steroid Biochem Mol Biol 1996; 58(4): 439–45

    Article  PubMed  CAS  Google Scholar 

  12. Geisler J, King N, Dowsett M, et al. Influence of anastrozole (Arimidex), a selective, non-steroidal aromatase inhibitor, on in vivo aromatisation and plasma oestrogen levels in postmenopausal women with breast cancer. Br J Cancer 1996; 74: 1286–91

    Article  PubMed  CAS  Google Scholar 

  13. Dowsett M, Lonning PE. Anastrozole- a new generation in aromatase inhibition: clinical pharmacology. Oncology 1997; 54Suppl. 2: 11–4

    Article  PubMed  CAS  Google Scholar 

  14. Yates RA, Dowsett M, Fisher GV, et al. Arimidex (ZD1033): a selective, potent inhibitor of aromatase in postmenopausal female volunteers. Br J Cancer 1996 Feb; 73: 543–8

    Article  PubMed  CAS  Google Scholar 

  15. Lønning PE, Geisler J, King N, et al. Influence of Arimidex (anastrozole), a non-steroidal aromatase inhibitor, on in vivo aromatisation and plasma estrogen levels in postmenopausal women with breast cancer [abstract]. Breast Cancer Res Treat 1996; 37 Suppl: 72

    Google Scholar 

  16. Kleeberg UR, Dowsett M, Carrion RP, et al. Arandomised comparison of oestrogen suppression with anastrozole and formestane in postmenopausal patients with advanced breast cancer. Oncology 1997; 54Suppl. 2: 19–22

    Article  PubMed  CAS  Google Scholar 

  17. Jonat W, Howell A, Blomqvist C, et al. Arandomised trial comparing two doses of the new selective aromatase inhibitor anastrozole (Arimidex) with megestrol acetate in postmenopausal patients with advanced breast cancer. Eur J Cancer A 1996 Mar; 32A: 404–12

    Article  PubMed  CAS  Google Scholar 

  18. Dowsett M, Welch H, Blackman GM, et al. A randomised, double-blind, parallel-group trial to evaluate the effect of Arimidex (anastrozole) on the pharmacokinetics of tamoxifen in postmenopausal breast cancer patients [abstract]. Breast 1997 Aug; 6(4): 245

    Google Scholar 

  19. Brodie A, Qing L, Yang L, et al. Preclinical studies using the intratumoral aromatase model for postmenopausal breast cancer. Oncology 1998; 12: 36–40

    PubMed  CAS  Google Scholar 

  20. Wolter J, Robert N, Harvey H, et al. Arimidex (ZD1033): a phase I study of a new, selective orally active aromatase inhibitor in postmenopausal women with advanced breast cancer [abstract]. Proc Am Soc Clin Oncol 1995 Mar; 14: 119

    Google Scholar 

  21. Plourde PV, Yates RA, Dyroff M, et al. The effect of Arimidex™, a new potent aromatase inhibitor, on circulating estrogens in post-menopausal women [abstract]. Proc Am Soc Clin Oncol 1993 Mar; 12: 91

    Google Scholar 

  22. Anastrozole. PDR Generics, 4th ed., Medical Economics, New Jersey, 1998: 198–200

    Google Scholar 

  23. Baldinger SL, DeFusco P. Focus on anastrozole: an aromatase inhibitor for the treatment of hormonally dependent advanced breast cancer. Formulary 1996 May; 31: 363–73

    Google Scholar 

  24. Bioavailability of Arimidex: effect of food and comparison of bioavailability of Arimidex tablet and an oral solution. Data for Clinical Invetigators 5th Ed., Jun 1995, Chester, England. Zeneca (Data on file)

  25. Metabolism of anastrozole in healthy postmenopausal female volunteers. Data for Clinical Investigators 5th Ed., Jun 1995. Chester, England. Zeneca (Data on file)

  26. Predictable pharmacokinetics of Arimidex when administered orally for periods of up to seventy-six weeks. Arimidex Pharmacology Summary Report, Chester, England. Zeneca (Data on file)

  27. Zeneca Pharma. Arimidex™. ABPI Compendium of Data Sheets and Summaries of Product Characteristics. Datapharm publications Limited, London, 1507

  28. Dowsett M, Yates R, Wong YWJ, et al. Arimidex (anastrozole): lack of interactions with tamoxifen, antipyrine, cimetidine and warfarin [abstract]. Eur J Cancer 1998 Feb; 34Suppl. 1: S39–40

    Article  Google Scholar 

  29. Buzdar AU, Jones SE, Vogel CL, et al. A phase III trial comparing anastrozole (1 and 10 milligrams), a potent and selective aromatase inhibitor, with megestrol acetate in postmenopausal women with advanced breast carcinoma. Cancer 1997; 79: 730–9

    Article  PubMed  CAS  Google Scholar 

  30. Buzdar AU, Jonat W, Howell A, et al. Anastrozole versus megestrol acetate in postmenopausal women with advanced breast cancer: results of a survival update based on a combined analysis of data from 2 mature phase III trials. Cancer. In press

  31. Hayward JL, Carbone PP, Henson JC, et al. Assessment of response to therapy in advanced breast cancer. Eur J Cancer 1977; 13: 89–94

    Article  Google Scholar 

  32. de Haes JCJM, van Knippenberg FCE, Neijt JP. Measuring psychological and physical distress in cancer patients: structure and application of the Rotterdam Symptom Checklist. Br J Cancer 1990; 62: 1034–8

    Article  PubMed  Google Scholar 

  33. Buzdar A, Jonat W, Howell A, et al. Anastrozole, a potent and selective aromatase inhibitor, versus megestrol acetate in postmenopausal women with advanced breast cancer: results of overview analysis of two phase III trials. J Clin Oncol 1996 Jul; 14: 2000–11

    PubMed  CAS  Google Scholar 

  34. Baum M, Houghton J, On behalf of the ATAC Steering Committee UK. Arimidex, tamoxifen alone or in combination (ATAC) adjuvant trial in post-menopausal breast cancer [abstract]. Eur J Cancer 1998 Feb; 34Suppl. 1: S39

    Article  Google Scholar 

Download references

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Correspondence to Lynda R. Wiseman.

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Wiseman, L.R., Adkins, J.C. Anastrozole. Drugs & Aging 13, 321–332 (1998). https://doi.org/10.2165/00002512-199813040-00008

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