A recent study led by a group of researchers at the University of Texas MD Anderson Cancer Center has found that adding a drug, ribociclib, to hormone therapy significantly increased the overall survival in relatively younger women suffering from advanced breast cancer.
The study covered women who had not yet reached menopause or were still going through it. They were suffering from hormone receptor-positive (HR+) breast cancer and HER2-negative disease. HR+ cancer involves tumours that are receptive to anti-estrogen (endocrine) treatments aimed at blocking hormones while HER2-negative means that the patient lacks a protein of that name.
What the study found
Described as “one of the greatest advances in breast cancer in recent decades”, the study was conducted on 672 pre-menopausal women under age 59 years who had advanced HR+. After 42 months, 70% of the patients treated with combination therapy were alive as compared to 46% of those who received only the hormone therapy.
“Younger patients have been a particular concern, because breast cancer is known to be more aggressive and to be associated with poorer prognosis in younger women than in older women,” the researchers wrote in The New England Journal of Medicine, which will publish the article online on Tuesday, when the results are presented at the annual meeting of the American Society of Clinical Oncology, in Chicago.
Why it is significant
At the All India Institute of Medical Sciences, almost 35% of patients diagnosed with HR+ breast cancer and HER2-negative disease are under age 40. For such women, the standard treatment involved hormonal treatments such as tamoxifen to premenopausal patients and drugs called aromatase inhibitors to post-menopausal women.
One in every 28 Indian women — 1 in 22 in urban areas, 1 in 60 in rural areas — is likely to develop breast cancer during her lifetime. According to the World Health Organization (WHO), breast cancer is the most frequent cancer among women, impacting 2.1 million women each year, and also causes the highest number of cancer-related deaths among women — 6,27,000 or 15% in 2018. In India, breast cancer accounts for 14% of all cancers in women.
The drug in India
The drug was first approved by the Food and Drug Administration in 2017 for post-menopausal women with advanced breast cancer, and then in 2018 for younger women. Since then, several private hospitals are already advising the drug to a few patients.
“Private hospitals may be using it, but the drug is not available at any government hospital. If any patient opts for the treatment, they have to purchase it from outside. We have been using it on and off, but this is an extensive study confirming the positive results of the combination therapy. In the past, there have been several small-scale studies,” said Dr S V S Deo, Professor and Head of the Department of Surgical Oncology, AIIMS.
For women suffering from (HR+) breast cancer and HER2-negative disease, there exist three kinds of a line of drugs called CDK4/6 — ribociclib, palbociclib, and abemaciclib. The US FDA approved palbociclib in February 2015, for use in post-menopausal women with breast cancer of this type.
“While the first two are available in India and are in use, the third inhibitor is not yet introduced. This drug along with hormone therapy has to be given to a patient until disease progression,” said Dr P K Julka, senior director at Max Institute of Oncology Daycare Centre.
“Treatment using the drug is quite expensive and not every patient can afford it. The cost of the drug is around Rs 50,000-60,000 per month and the duration varies from patient to patient. Definitely, it is a boost to the survivors since it increases the life duration,” Dr Julka said.
Recently, the National Pharmaceutical and Pricing Authority capped the prices of 42 medicines used to treat different types of cancers. The list included ribociclib.
“Introduction of any medicine is a lengthy process. The manufacturing company will have to think of ways for making the medicine available to the patient belonging to different categories. The role of the Government of India is important; if the government intervenes, it may be affordable for the public,” Dr Deo said.
A few experts note that delaying of progression will only allow the patient to live a little longer.
“The results are positive but we need to also understand the survival rate. With the help of this medicine, we are able to extend the life duration but the patient relapses at the end. The drug has an advantage over chemotherapy,” said Dr Vinod Raina, Director of Medical Oncology at Fortis Memorial Research Institute.
“These targeted therapies are expensive and may have less side effects compared to standard treatment in this subset of women. But, overall survival benefits are still questionable,” said Dr Ravi Mehrotra, Director, National Institute of Cancer Prevention.