MedKoo product information:

 Formestane

Formestane is a synthetic steroidal substance with antineoplastic activity. Formestane binds irreversibly to and inhibits the enzyme aromatase, thereby blocking the conversion of cholesterol to pregnenolone and the peripheral aromatization of androgenic precursors into estrogens. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus).

Formestane belongs to a class of drugs known as 2 aromatase inhibitors. It is used in the treatment of estrogen-receptor positive breast cancer in post-menopausal women. It is available as an intramuscular depot injection (Lentaron). Formestane is often used to suppress estrogen production from anabolic steroids or prohormones. It also acts as a prohormone to 4-hydroxytestosterone, an active steroid which displays weak androgenic activity in addition to acting as a mild aromatase inhibitor. Formestane has poor oral bioavailability and as such is no longer popular as many orally available aromatase inhibitors have been developed. see http://en.wikipedia.org/wiki/Formestane.

  1: Santen RJ, Brodie H, Simpson ER, Siiteri PK, Brodie A. History of aromatase: saga of an important biological mediator and therapeutic target. Endocr Rev. 2009 Jun;30(4):343-75. Epub 2009 Apr 23. Review. PubMed PMID: 19389994.

2: Bhatnagar AS. The discovery and mechanism of action of letrozole. Breast Cancer Res Treat. 2007;105 Suppl 1:7-17. Epub 2007 Oct 3. Review. Erratum in: Breast Cancer Res Treat. 2008 Nov;112(2):385. PubMed PMID: 17912633; PubMed Central PMCID: PMC2001216.

3: Dutta U, Pant K. Aromatase inhibitors: past, present and future in breast cancer therapy. Med Oncol. 2008;25(2):113-24. Epub 2007 Nov 1. Review. PubMed PMID: 17973095.

4: Jordan VC, Brodie AM. Development and evolution of therapies targeted to the estrogen receptor for the treatment and prevention of breast cancer. Steroids. 2007 Jan;72(1):7-25. Epub 2006 Dec 13. Review. PubMed PMID: 17169390; PubMed Central PMCID: PMC2566956.

5: Mauri D, Pavlidis N, Polyzos NP, Ioannidis JP. Survival with aromatase inhibitors and inactivators versus standard hormonal therapy in advanced breast cancer: meta-analysis. J Natl Cancer Inst. 2006 Sep 20;98(18):1285-91. PubMed PMID: 16985247.

6: Carlini P, Bria E, Giannarelli D, Ferretti G, Felici A, Papaldo P, Fabi A, Nisticò C, Di Cosimo S, Ruggeri EM, Milella M, Mottolese M, Terzoli E, Cognetti F. New aromatase inhibitors as second-line endocrine therapy in postmenopausal patients with metastatic breast carcinoma: a pooled analysis of the randomized trials. Cancer. 2005 Oct 1;104(7):1335-42. Review. PubMed PMID: 16088965.

7: Spano JP, Khayat D, Delozier T. [Aromatase inhibitors in adjuvant setting in breast cancer]. Bull Cancer. 2004 Dec 1;91 Suppl 4:S239-43. Review. French. PubMed PMID: 15899615.

8: Sainsbury R. Aromatase inhibition in the treatment of advanced breast cancer: is there a relationship between potency and clinical efficacy? Br J Cancer. 2004 May 4;90(9):1733-9. Review. PubMed PMID: 15150604; PubMed Central PMCID: PMC2410276.

9: Miller WR, Anderson TJ, Evans DB, Krause A, Hampton G, Dixon JM. An integrated view of aromatase and its inhibition. J Steroid Biochem Mol Biol. 2003 Sep;86(3-5):413-21. Review. PubMed PMID: 14623539.

10: Carlini P, Ferretti G, Di Cosimo S, Colella E, Tonachella R, Romiti A, Tomao S, Frassoldati A, Papaldo P, Fabi A, Ruggeri EM, Cognetti F. Is there a benefit by the sequence anastrozole-formestane for postmenopausal metastatic breast cancer women? J Steroid Biochem Mol Biol. 2003 Jul;86(1):107-9. PubMed PMID: 12943750.

11: Vergote I, Robertson JF, Kleeberg U, Burton G, Osborne CK, Mauriac L; Trial 0020 Investigators; Trial 0021 Investigators. Postmenopausal women who progress on fulvestrant ('Faslodex') remain sensitive to further endocrine therapy. Breast Cancer Res Treat. 2003 May;79(2):207-11. PubMed PMID: 12825855.

12: Johnson PE, Buzdar A. Are differences in the available aromatase inhibitors and inactivators significant? Clin Cancer Res. 2001 Dec;7(12 Suppl):4360s-4368s; discussion 4411s-4412s. Review. PubMed PMID: 11916226.

13: Brodie A, Long B. Aromatase inhibition and inactivation. Clin Cancer Res. 2001 Dec;7(12 Suppl):4343s-4349s; discussion 4411s-4412s. Review. PubMed PMID: 11916223.

14: Brodie A. Aromatase inhibitors in breast cancer. Trends Endocrinol Metab. 2002 Mar;13(2):61-5. PubMed PMID: 11854020.

15: Carlini P, Frassoldati A, De Marco S, Casali A, Ruggeri EM, Nardi M, Papaldo P, Fabi A, Paoloni F, Cognetti F. Formestane, a steroidal aromatase inhibitor after failure of non-steroidal aromatase inhibitors (anastrozole and letrozole): is a clinical benefit still achievable? Ann Oncol. 2001 Nov;12(11):1539-43. PubMed PMID: 11822752.

16: Kerbrat P, Lefeuvre C. [Aromatase inhibitors: a review of clinical trials]. Bull Cancer. 2000 Dec;87 Spec No:31-39. Review. French. PubMed PMID: 11250606.

17: Buzdar A. An overview of the use of non-steroidal aromatase inhibitors in the treatment of breast cancer. Eur J Cancer. 2000 Sep;36 Suppl 4:S82-4. PubMed PMID: 11056331.

18: Bajetta E, Zilembo N, Bichisao E, Martinetti A, Buzzoni R, Pozzi P, Bidoli P, Ferrari L, Celio L. Tumor response and estrogen suppression in breast cancer patients treated with aromatase inhibitors. Ann Oncol. 2000 Aug;11(8):1017-22. PubMed PMID: 11038039.

19: Santen RJ, Harvey HA. Use of aromatase inhibitors in breast carcinoma. Endocr Relat Cancer. 1999 Mar;6(1):75-92. Review. PubMed PMID: 10732791.

20: Bajetta E, Zilembo N, Bichisao E. Aromatase inhibitors in the treatment of postmenopausal breast cancer. Drugs Aging. 1999 Oct;15(4):271-83. Review. PubMed PMID: 10582774.

21: Bernhard J, Thürlimann B, Schmitz SF, Castiglione-Gertsch M, Cavalli F, Morant R, Fey MF, Bonnefoi H, Goldhirsch A, Hürny C. Defining clinical benefit in postmenopausal patients with breast cancer under second-line endocrine treatment: does quality of life matter? J Clin Oncol. 1999 Jun;17(6):1672-9. PubMed PMID: 10561203.

22: Dowsett M, Doody D, Miall S, Howes A, English J, Coombes RC. Vorozole results in greater oestrogen suppression than formestane in postmenopausal women and when added to goserelin in premenopausal women with advanced breast cancer. Breast Cancer Res Treat. 1999 Jul;56(1):25-34. PubMed PMID: 10517340.

23: Michaud LB, Buzdar AU. Risks and benefits of aromatase inhibitors in postmenopausal breast cancer. Drug Saf. 1999 Oct;21(4):297-309. Review. PubMed PMID: 10514021.

24: de Jong PC, Blijham GH. New aromatase inhibitors for the treatment of advanced breast cancer in postmenopausal women. Neth J Med. 1999 Aug;55(2):50-8. Review. PubMed PMID: 10474272.

25: Njar VC, Brodie AM. Comprehensive pharmacology and clinical efficacy of aromatase inhibitors. Drugs. 1999 Aug;58(2):233-55. Review. PubMed PMID: 10473018.

26: Lønning PE. Aromatase inhibitors and their future role in post-menopausal women with early breast cancer. Br J Cancer. 1998 Sep;78 Suppl 4:12-5. PubMed PMID: 9741783; PubMed Central PMCID: PMC2062757.

27: Friedrichs K, Jänicke F. [Aromatase inhibitors--new possibilities in treatment of breast carcinoma]. Praxis (Bern 1994). 1998 Apr 22;87(17):584-8. Review. German. PubMed PMID: 9623325.

28: Kelloff GJ, Lubet RA, Lieberman R, Eisenhauer K, Steele VE, Crowell JA, Hawk ET, Boone CW, Sigman CC. Aromatase inhibitors as potential cancer chemopreventives. Cancer Epidemiol Biomarkers Prev. 1998 Jan;7(1):65-78. Review. PubMed PMID: 9456245.

29: Roseman BJ, Buzdar AU, Singletary SE. Use of aromatase inhibitors in postmenopausal women with advanced breast cancer. J Surg Oncol. 1997 Nov;66(3):215-20. Review. PubMed PMID: 9369969.

30: Bajetta E, Zilembo N, Barni S, Noberasco C, Martinetti A, Ferrari L, Schieppati G, Buzzoni R, Jirillo A, Amichetti M, D'Aprile M, Comella G, Bichisao E, Bolelli GF, Attili A, Bombardieri E. A multicentre, randomized, pharmacokinetic, endocrine and clinical study to evaluate formestane in breast cancer patients at first relapse: endocrine and clinical results. The Italian Trials in Medical Oncology (I.T.M.O.) group. Ann Oncol. 1997 Jul;8(7):649-54. PubMed PMID: 9296217.

31: Dowsett M. Aromatase inhibitors come of age. Ann Oncol. 1997 Jul;8(7):631-2. PubMed PMID: 9296213.

32: Rubens RD. Aromatase inhibitors for breast cancer--further progress. Eur J Cancer. 1997 Jun;33(7):989-90. PubMed PMID: 9376202.

33: Trunet PF, Vreeland F, Royce C, Chaudri HA, Cooper J, Bhatnagar AS. Clinical use of aromatase inhibitors in the treatment of advanced breast cancer. J Steroid Biochem Mol Biol. 1997 Apr;61(3-6):241-5. Review. PubMed PMID: 9365196.

34: 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. Review. PubMed PMID: 8894526.

35: Rose C. Proper sequence of endocrine therapies in advanced breast cancer. Acta Oncol. 1996;35 Suppl 5:44-9. Review. PubMed PMID: 9142964.

36: De Coster R, Wouters W, Bruynseels J. P450-dependent enzymes as targets for prostate cancer therapy. J Steroid Biochem Mol Biol. 1996 Jan;56(1-6 Spec No):133-43. Review. PubMed PMID: 8603034.

37: Lønning PE, Ekse D. A sensitive assay for measurement of plasma estrone sulphate in patients on treatment with aromatase inhibitors. J Steroid Biochem Mol Biol. 1995 Dec;55(3-4):409-12. PubMed PMID: 8541238.

38: Brodie AM, Santen RJ. Aromatase and its inhibitors in breast cancer treatment--overview and perspective. Breast Cancer Res Treat. 1994;30(1):1-6. Review. PubMed PMID: 7949200.

39: Brodie AM. Aromatase, its inhibitors and their use in breast cancer treatment. Pharmacol Ther. 1993 Dec;60(3):501-15. Review. PubMed PMID: 8073072.

40: Höffken K. Experience with aromatase inhibitors in the treatment of advanced breast cancer. Cancer Treat Rev. 1993 Apr;19 Suppl B:37-44. Review. PubMed PMID: 8481933.

41: Hayes RA, Miller K, Akira S, Lin YC, Friedman CI, Kim MH. Pregnancy can be established in superovulated adult rats treated with progesterone and an aromatase inhibitor. Life Sci. 1993;52(1):61-71. PubMed PMID: 8417279.

42: Wiseman LR, McTavish D. Formestane. A review of its pharmacodynamic and pharmacokinetic properties and therapeutic potential in the management of breast cancer and prostatic cancer. Drugs. 1993 Jan;45(1):66-84. Review. PubMed PMID: 7680986.

43: Dowsett M, Stein RC, Coombes RC. Aromatization inhibition alone or in combination with GnRH agonists for the treatment of premenopausal breast cancer patients. J Steroid Biochem Mol Biol. 1992 Sep;43(1-3):155-9. Review. PubMed PMID: 1388047.

44: Brodie A. Aromatase and its inhibitors--an overview. J Steroid Biochem Mol Biol. 1991;40(1-3):255-61. Review. PubMed PMID: 1958529.

45: Dowsett M. Clinical development of aromatase inhibitors for the treatment of breast and prostate cancer. J Steroid Biochem Mol Biol. 1990 Dec 20;37(6):1037-41. Review. PubMed PMID: 2149504.

46: Santen RJ. Recent progress in development of aromatase inhibitors. J Steroid Biochem Mol Biol. 1990 Dec 20;37(6):1029-35. Review. PubMed PMID: 2149503.

47: Shearer RJ, Davies JH, Dowsett M, Malone PR, Hedley A, Cunningham D, Coombes RC. Aromatase inhibition in advanced prostatic cancer: preliminary communication. Br J Cancer. 1990 Aug;62(2):275-6. PubMed PMID: 2201397; PubMed Central PMCID: PMC1971817.

48: Wilkinson JR, Williams JC, Singh D, Goss PE, Easton D, Coombes RC. Response of nitrosomethylurea-induced rat mammary tumor to endocrine therapy and comparison with clinical response. Cancer Res. 1986 Sep;46(9):4862-5. PubMed PMID: 3731133.

49: Brodie AM, Santen RJ. Aromatase in breast cancer and the role of aminoglutethimide and other aromatase inhibitors. Crit Rev Oncol Hematol. 1986;5(4):361-96. Review. PubMed PMID: 3094971.