Striving for Better Care

More treatment options are needed to extend and improve the lives of New Zealanders with advanced breast cancer. 

Different medicines are needed for the different sub-types of breast cancer (hormone receptor positive/negative, HER2 positive/negative, triple negative, etc.), and different patients with the same sub-type may respond differently to a single medicine. On top of this, as breast cancer progresses, different medicines are needed to suppress tumour growth and spread.

This is why advanced breast cancer patients have a variety of treatment pathways, involving different sequences and combinations of drugs. Not everyone receives each drug, and as soon as a patient’s cancer progresses, they are moved on to a new drug or combination of drugs (a new ‘treatment line’).

When treating advanced breast cancer, oncologists aim to maximise the quality and length of life for each patient by individually tailoring their treatments, so that the most effective treatment line can be used when it is needed. It is by no means a one-size-fits-all situation, and to get the best outcomes, both patients and oncologists need access to a range of drugs.

Overseas and New Zealand research shows that the more lines of treatment given, the longer patients with advanced cancer live, with a better quality of life.  In New Zealand, few patients receive more than 2 or 3 lines of treatment and between 10 and 30% receive no systemic drug treatment after diagnosis at all [1].

Recently three more medicines for treating advanced breast cancer (Ibrance®, Kadcyla®, Faslodex®) were approved in New Zealand [2]. This is good news but there are more that we could and should be able to access.

Medicines recommended in European guidelines [3] for the treatment of advanced breast cancer but not funded in New Zealand (as at August 2020) include:

Everolimus (brand name Afinitor®) is recommended for second- or later-line treatment of hormone receptor positive, HER2 negative advanced breast cancer, in conjunction with an aromatase inhibitor. In 2018 BCAC applied to PHARMAC for everolimus to be funded, but this was declined in 2019.

Eribulin (brand name Halaven®) is recommended for use in patients with advanced hormone receptor positive, HER2 negative, or triple negative breast cancer whose disease has progressed after treatment with chemotherapy (anthracycline or taxanes). Eribulin has been funded in Australia (since 2014), Canada (2012), France (2015), United Kingdom (2016) and Scotland (2016). There is currently no application before PHARMAC for this medicine.

PARP inhibitors (such as Olaparib®) are recommended for later-line treatment of advanced triple negative breast cancer in patients carrying a BRCA mutation. Olaparib has been funded in New Zealand for the treatment of ovarian cancer in patients with a BCRA mutation, but not for those with breast cancer.

Trastuzumab beyond progression: In New Zealand, trastuzumab (Herceptin®) is funded for use either alone or with pertuzumab (Perjeta®) as a first-line treatment for HER2-positive advanced breast cancer. After progression, trastuzumab emtansine (T-DM1 or Kadcyla®) is funded for second-line use.  When that fails, international guidelines recommend third-line treatment with trastuzumab combined with lapatinib (Tykerb®) or chemotherapy that has not been used before. In New Zealand, trastuzumab cannot be used more than once after a diagnosis of advanced breast cancer, and only chemotherapies (which usually have significant side effects) can be given at this stage.

In 2019, BCAC presented a petition to the Health Select Committee asking the government to provide sufficient funding to PHARMAC to subsidise all of the drugs listed in the European guidelines for the treatment of advanced breast cancer [3, 4].

BCAC’s submission in support of this petition can be read here [5].

As of August 2020, there has been no written report from the Health Select Committee in response to this petition.

New medicines on the horizon for advanced breast cancer include the following: 

For triple negative breast cancer

Atezolizumab (brand name Tecentriq®) is an immunotherapy drug used for treating triple negative breast cancer. After promising early clinical trial results, it was given provisional funding in Australia and the United Kingdom. In New Zealand, pharma company Roche has applied to PHARMAC for funded access and currently offers it to patients via a Cost Share Programme (contact nz.costshare@roche.com for more information).  In August 2020, disappointing results from the latest Phase III trial (called IMpassion131) were published; patients receiving it had failed to show significant improvement in progression free survival. The impact of these results on the availability of this medicine in New Zealand are not yet clear. Further clinical trials using atezolizumab combined with other drugs for metastatic breast cancer are under way.

Sacituzumab govetican (brand name Trodelvy®) is another immunotherapy drug used to treat triple negative breast cancer. It was given accelerated approval by the FDA in the United States in April 2020, when the phase III ASCENT clinical trial showed ‘compelling evidence of efficacy’. It is produced by pharma company Immunomedics. It is not funded in Australia and is not approved by Medsafe or funded by PHARMAC in New Zealand.

Ipatasertib (no brand name yet) is another Roche drug being investigated for use in patients with metastatic triple negative breast cancer. It is an inhibitor of an enzyme called AKT which can be overactive in some cancers.  In the Phase III clinical trial called IPATunity170, patients are being given ipatasertib plus atezolizumab (Tecentriq) plus paclitaxel.

For hormone receptor positive, HER2-negative breast cancer

Alpelisib (brand name PIQRAY®) is a drug which inhibits an enzyme called PI3K that is involved in cell proliferation.  Some patients with advanced hormone receptor positive, HER2-negative breast cancer have a mutation that means they over-produce PI3K and so they can benefit from alpelisib. This drug is sold by Novartis along with a test kit for the mutation, so that those who will benefit can be identified before taking it. The FDA in the United States approved this medicine in May 2019. It is not approved by Medsafe or funded by PHARMAC in New Zealand.

For HER2-positive breast cancer

Trastuzumab deruxtecan (brand name Enhertu®) is a new drug for advanced HER2-positive breast cancer currently being tested in Phase III clinical trials. It targets the HER2 receptor and delivers a chemotherapy drug directly to the tumour cells. It is thought to work better than current anti-HER2 drugs for those whose tumours express HER2 only at low levels. Astra Zeneca have developed Enhertu in collaboration with Japanese company Daiichi Sankyo. In July 2020, the European Medicines Agency (which assesses efficacy and safety of new drugs) granted 'accelerated assessment' for Enhertu. It is not approved by Medsafe or funded by PHARMAC in New Zealand.

Further information:

19 August 2020

 

References

[1] Breast Cancer Foundation NZ. “I’m still here”. Insights into living – and dying – with Advanced Breast Cancer in New Zealand. September 2018. https://breastcancerfoundation.org.nz/Images/Assets/21894/1/BCFNZ-ABC-Report-2018-Executive-Summary.pdf

[2] Petition of Terre Maize: Fund Kadcyla and Palbociclib for breast cancer sufferers

BCAC’s role in fulvestrant funding: https://www.breastcancer.org.nz/about-us/submissions

[3] 4th ESO-ESMO International Consensus Guidelines for Advanced Breast Cancer (ABC 4) Annals of Oncology, Vol. 29, Issue 8, 1 August 2018, pages 1634-1657. https://www.esmo.org/content/download/181639/3308758/1/Clinical-Practice-Guidelines-Slideset-Advanced-Breast-Cancer.pdf

[4] Petition of Emma Crowley for BCAC: Fund breast cancer drugs

[5] BCAC's submission in support of the Petition of Emma Crowley's for BCAC: Fund breast cancer drugs