Tens of thousands more women at increased risk of breast cancer could now benefit from a proven risk-reducing drug on the NHS, after it was licensed in a new use to help prevent the disease.

Anastrozole, which has been used for many years as a breast cancer treatment, has today been licensed by the Medicines and Healthcare products Regulatory Agency (MHRA) as a preventive option – which it is hoped could help prevent around 2,000 cases of breast cancer in England.

The drug, which is off-patent, has been shown in trials to reduce the incidence of the disease in post-menopausal women at increased risk of the disease by almost 50%.

It was first recommended as a preventive option by the National Institute for Health and Care Excellence in 2017, however, with the treatment being unlicensed in this use, uptake has remained low.

Thanks to a pioneering Medicines Repurposing Programme led by NHS England, the drug has today been granted a new indication by the MHRA as a preventive option for women at increased risk, including those with a significant family history of the disease.

Around 289,000 women at moderate or high risk of breast cancer could be eligible for the drug, and while not all will choose to take it, it is estimated that if 25% do, around 2,000 cases of breast cancer could potentially be prevented in England, while saving the NHS around £15 million in treatment costs.

NHS chief executive, Amanda Pritchard, said: “It’s fantastic that this vital risk-reducing option could now help thousands of women and their families avoid the distress of a breast cancer diagnosis.

“Allowing more women to live healthier lives, free of breast cancer is truly remarkable, and we hope that licensing anastrozole for a new use today represents the first step to ensuring this risk-reducing option can be accessed by all who could benefit from it.

“This is the first drug to be repurposed through a world-leading new programme to help us realise the full potential of existing medicines in new uses to save and improve more lives on the NHS. Thanks to this initiative, we hope that greater access to anastrozole could enable more women to take risk-reducing steps if they’d like to, helping them live without fear of breast cancer.”

Lesley-Ann Woodhams, 61, was offered anastrozole off-label for the prevention of breast cancer due to being at increased risk of developing the disease, and having a family history of breast cancer. Lesley-Ann completed the full five-year course of anastrozole in January 2023.

She said: “Taking anastrozole was an easy decision for me, as I’d watched my mum battle breast cancer and my risk was very high. Anastrozole reduced my risk of developing breast cancer, meaning I could live a life without constantly worrying or giving a thought to what could be if I’d developed breast cancer. It really was a gift, it gave my family and myself peace of mind and more importantly, a continued future to look forward to. I’m grateful for every day I took this drug – it was life-changing. Anastrozole has allowed me to continue living my life as I’d planned.”

Breast cancer remains the most common cancer in England, with 47,000 people being diagnosed each year. Thanks to advances in screening, treatment and care alongside NHS awareness campaigns, more women are surviving the disease than ever before.

Anastrozole today becomes the first medicine to be repurposed through a new multi-agency national programme that looks at using existing medicines in new ways to benefit patients and the NHS.

The Medicines Repurposing Programme, set up in 2021, is hosted by NHS England and supported by DHSC, the MHRA, NICE, and the NIHR, and builds on the innovation in medicines repurposing seen during the COVID-19 pandemic, which saw tocilizumab, an arthritis drug, and dexamethasone, a widely available steroid, repurposed as treatments for COVID-19.

The licensing work was undertaken by Accord Healthcare on a not-for-profit basis, after Accord Healthcare was selected through an open competitive process. The Medicines Repurposing Programme will now work with the MHRA and the British Generic Manufacturers Association to ensure other companies that make anastrozole adopt the new licensed indication.

The treatment is taken as a 1mg tablet, once a day for five years. Anastrozole is an aromatase inhibitor. This works by cutting down the amount of the hormone oestrogen that a patient’s body makes by blocking an enzyme called ‘aromatase’.

The most common side effects of the medicine are hot flushes, feeling weak, pain/stiffness in the joints, arthritis, skin rash, nausea, headache, osteoporosis, and depression. Anyone who suspects they are having a side effect from this medicine is encouraged to talk to their doctor, pharmacist or nurse and report it directly to the MHRA’s Yellow Card scheme.

Health Minister, Will Quince, said: “Breast cancer is the most common cancer in the UK so I’m delighted that another effective drug to help to prevent this cruel disease has now been approved.

“We’ve already seen the positive effect Anastrozole can have in treating the disease when it has been detected in post-menopausal women and now we can use it to stop it developing at all in some women.

“This is a great example of NHS England’s innovative Medicines Repurposing Programme supporting the development of new ways for NHS patients to benefit from existing treatments.”

Dame June Raine, Chief Executive of the MHRA, said: “This innovative Programme is essential to support and advance research into medicines that might be repurposed, increase access to life-saving medicines and, ultimately, improve patients’ lives. The MHRA welcomes applications for repurposed medicines and encourages early dialogue from companies or developers considering this.”

Baroness Delyth Morgan, chief executive at Breast Cancer Now, said: “The extension of anastrozole’s licence to cover it being used as a risk-reducing treatment is a major step forward that will enable more eligible women with a significant family history of breast cancer, to reduce their chance of developing the disease.

“For the past decade, Breast Cancer Now has been tirelessly campaigning with clinicians, researchers and patients for drugs that are found to be effective and safe in new uses to reach people who could benefit, and we were thrilled when NHS England set up the Medicines Repurposing Programme. Anastrozole was the first drug to be supported by the programme and this paves the way for improving access to risk-reducing drugs. We look forward to continuing our work with NHS England to further improve access to these drugs for everyone eligible.”

Jonathan Wilson, Senior Vice President at Accord Healthcare said: “We believe in the untapped potential of existing medicines to serve broader healthcare needs. Our work with the Medicines Repurposing Programme isn’t just about innovation; it’s about creating real, measurable outcomes for patients.

“By obtaining this licence variation in partnership with the Programme, we’ve not only expanded treatment options but also provided renewed hope for thousands of individuals. It’s a profound step forward, validating our commitment to collaboratively advancing healthcare with quality, safety, and efficacy at the forefront.”