‘Landmark’ drug halts advance of breast cancer
Treatment can shrink tumours and stall disease progression for twice as long as existing therapies
A BREAKTHROUGH breast cancer drug that can treat the most common form of the disease has been hailed as a “landmark” moment.
Around 8,000 women in the UK could benefit from the treatment which can shrink tumours and stall disease for twice as long as previous medicines.
Experts said the findings were “fantastic” and could mean patients will be able to live well and longer in the advanced stages of the disease.
The results of a phase III clinical trial of capivasertib alongside hormone therapy suggest that the combination could become the new treatment for patients with advanced forms of the most common type of breast cancer.
The findings, which were presented at the San Antonio Breast Cancer Symposium yesterday, relate to oestrogen receptor (ER) positive, human epidermal growth factor receptor 2 (HER-2) negative breast cancer, which accounts for around 70 per cent of all new breast cancer cases.
Capivasertib is being manufactured by Astrazeneca, the pharmaceutical giant, following research at the Institute of Cancer Research (ICR) in London. The drug’s novel action blocks activity of the cancer-driving protein molecule AKT.
Prof Kristian Helin, chief executive and president of the ICR, said: “This is a landmark moment for the treatment of advanced forms of the most common type of breast cancer. It’s incredibly exciting to see a drug that was discovered following research conducted at the ICR now show remarkable benefits for patients in a phase III trial.
“Capivasertib could offer a completely new treatment option for these patients. This is a major success story for UK science: [it] showcases the benefits of collaboration between academia, charities and industry to bring gamechanging new treatments to people with cancer as quickly as possible.”
Prof Helin said he hoped longer-term follow-up results would show that patients lived longer on the new drug combination. “But the existing findings are already strong enough for capivasertib to be submitted to regulators to be considered for approval as a new breast cancer treatment,” he said.
All patients on the trial, led by researchers at the ICR and the Royal Marsden NHS Foundation Trust, had seen their cancer recur or progress on standard hormone treatments, and the majority had also previously been treated with CDK4/6 inhibitors, which are drugs that block cancer cells from multiplying. At present, patients whose cancer progresses continue to receive fulvestrant hormone therapy, but this is often not effective, and many are only left with the option of chemotherapy.
For the research, scientists randomly assigned 355 patients to receive capivasertib plus fulvestrant and 353 patients a placebo plus fulvestrant. The results showed that treatment with capivasertib plus fulvestrant typically gave patients 7.2 months without their disease progressing or getting worse, compared with 3.6 months for patients treated with a placebo plus fulvestrant.
The treatment shrank tumours in 23 per cent of patients, compared with 12 per cent who received fulvestrant plus a placebo. The new drug regime was also more effective for the four in 10 patients whose cancers had mutations to the AKT signalling pathway, with 29 per cent seeing their tumours shrink compared with 10 per cent on the placebo. Genetic alterations to the AKT pathway can drive both cancer’s development and resistance to treatment.
Trial leader Nick Turner, professor of molecular oncology at the ICR and consultant oncologist at the Royal Marsden, said: “This is a fantastic finding for patients with breast cancer. People with this type of advanced breast cancer will [still] eventually see their cancer stop responding to treatment.
“We’re delighted this potential firstin-class drug combined with hormone therapy can lower the progression of these advanced cancers.”