In final guidance, the National Institute for Health and Clinical Excellence (NICE) says that widespread use of AstraZeneca's breast cancer drug Faslodex (fulvestrant) would not be an effective use of NHS resources.

Faslodex is licensed as alternative to aromatase inhibitors for postmenopausal women who have oestrogen-receptor-positive, locally advanced or metastatic breast cancer, and who have already received anti-oestrogen therapy. However, NICE's final guidance concludes that the drug does not work significantly better than existing treatments.

AstraZeneca had estimated that Faslodex could extend life when compared to the currently-prescribed aromatase inhibitors - the firm's own Arimidex (anastrazole) and Novartis' Femara (letrozole) - but NICE's independent appraisal committee found these estimates to be "considerably uncertain," and concluded that it had not been given any conclusive evidence that Faslodex extends life or delays tumour progression any more than aromatase inhibitor therapy, the Institute reports.

However, NICE adds that, importantly, the guidance states that women who are currently receiving the drug as an alternative to aromatase inhibitors after they have received anti-oestrogen treatment should be able to continue to do so until they and their doctors consider it appropriate to stop.

Decisions on the use of Faslodex outside of its licensed indication (eg, after an aromatase inhibitor) are still made at local NHS level, NICE adds.

NICE chief executive Sir Andrew Dillon commented that while there is evidence that Faslodex can delay the growth of breast cancer, the advisory committee found that, when used according to its marketing authorisation, the drug’s effectiveness is uncertain compared to aromatase inhibitors, which are currently the preferred treatment options on the NHS.

"Confidence about the additional benefits new treatments bring is important both for patients and for those who have responsibility for managing the resources available to the NHS," Sir Andrew added.

NICE also reports that the appraisal committee had considered it likely that the population covered by Faslodex's marketing authorisation would be small, given the restriction to patients who have previously received an anti-oestrogen, the declining use of tamoxifen and the increasing use of aromatase inhibitors. However, the precise population size is uncertain, it added.

Turning to the product's costs, the committee concluded that while the Incremental Cost Effectiveness Ratio (ICER) of £35,000 per Quality-Adjusted Life Year (QALY) for Faslodex 500mg compared with Arimidex was the most plausible estimate presented, this estimate was associated with considerable uncertainty.

It also found that Faslodex did not fulfil all of NICE's end-of-life criteria, because the CONFIRM (COmparisoN of FASLODEX in Recurrent or Metastatic breast cancer) trial had showed that the drug is indicated for women who have a life expectancy greater than 24 months.

- CONFIRM is a Phase III, randomised, double-blind, parallel-group, multi-center trial comparing Faslodex 500mg and 250mg in postmenopausal women with oestrogen receptor-positive advanced breast cancer, failing on prior endocrine therapy (anti-oestrogen or aromatase inhibitor).