Teaching old drugs new tricks: preventing breast cancer with a repurposed medicine

Hundreds of items can be used for more than one thing: spaghetti is delicious (no white T-shirts please), tells you when a cake is done and makes an excellent play dough hedgehog. Vinegar makes chips tasty and windows shiny. So why not find new uses for medicines, too? It was this way of thinking which led to the creation of England’s Medicines Repurposing programme, established in March 2021 to identify and progress opportunities to use existing medicines in new ways.

The Medicines Repurposing programme provides tailored support for prioritised medicines that could benefit patients and the NHS. It is a collaboration of national agencies including the Department of Health and Social Care, the Medicines and Healthcare products Regulatory Agency, the National Institute for Health and Care Excellence, and the National Institute for Health and Care Research, with support from the Association of Medical Research Charities.

What is the programme doing?

In a major step, NHS England has signed a first-of-its-kind agreement to repurpose a medicine currently used to treat breast cancer, to potentially help prevent thousands of cases of breast cancer. Research shows that the drug, anastrozole, can help to prevent breast cancer when it is taken by postmenopausal people at increased risk of the disease.

NHS England is working with a pharmaceutical company, Accord, and the Medicines and Healthcare products Regulatory Agency (MHRA) to get an independent assessment of using the drug for preventative purposes. The MHRA will decide whether to grant a variation to anastrozole’s licence which would expand its use from a treatment for breast cancer to also be a preventative drug for breast cancer.

Why anastrozole?

Clinical trial data shows that anastrozole can deliver a 49% reduction in breast cancer occurrence, over a nearly 11-year period, when it is taken by postmenopausal people at increased risk. Therefore, it enables nearly half of the people who receive it to live their lives free of breast cancer for over a decade. The use of anastrozole as a preventative drug is not currently covered by the medicine’s licence, which means it is not commonly used despite a clear benefit to patients. If the licence variation is granted by the MHRA, it will provide reassurance to patients and doctors that using anastrozole to prevent breast cancer is safe and effective.

In addition to supporting the licensing decision, a working group has been set up to consider additional ways to improve access to anastrozole as a preventative therapy – for example by providing information for prescribers.

NHS England estimates that this work on anastrozole could enable up to 79,000 people in England to receive the drug for preventative purposes, which would prevent around 2,257 cases of breast cancer. Using anastrozole in this way would save the NHS in England £14.7 million by avoiding the costs of cancer treatment. The entire 5-year treatment course with anastrozole currently costs just £78 per person.

The licensing work is being done by Accord on a not-for-profit basis and should cost less than £30,000.

How to get involved

The Medicines Repurposing Programme welcomes new proposals from healthcare professionals, charities and companies. To learn more about what we are looking for and to propose a potential candidate, please view the interim eligibility criteria and candidate proposal form.

You can get in touch with the team at and subscribe to our mailing list using the same email address.

Rosie Lovett

Rosie Lovett is the Head of the Medicines Repurposing Programme> at NHS England. She completed a PhD in Psychology at the University of York and post-doctoral research at University College London, before joining the Technology Appraisals and Science Policy and Research teams at the National Institute for Health and Care Excellence (NICE).