Everolimus in hormone-resistant breast cancer

Everolimus is a targeted tablet that blocks mTOR, a protein in a growth pathway that hormone-sensitive breast cancers can use to keep growing when hormone therapy stops working. It is used with exemestane, an aromatase inhibitor, for postmenopausal women with hormone receptor positive, HER2-negative metastatic breast cancer that has grown on an earlier non-steroidal aromatase inhibitor such as letrozole or anastrozole. Studies showed the combination controlled the cancer for longer than exemestane alone. It does not require a mutation test.

Why it helps hormone therapy work again

When cancers become resistant to hormone therapy, the mTOR pathway is often more active. Blocking it can restore sensitivity to hormone treatment, so the two drugs work better together.

The side effects to plan for

Mouth sores are the most common problem, especially in the first weeks, and a steroid mouthwash can prevent many of them. Other effects include rash, tiredness, high blood sugar and cholesterol, and, less often, lung inflammation.

Who may not be suitable

People with significant lung disease, poorly controlled diabetes, active infections or severe liver problems, and those taking medicines that interact strongly.

Everolimus with exemestane can keep hormone-resistant metastatic breast cancer under control for longer than hormone therapy alone. It has not been clearly shown to help people live longer, and side effects lead some people to reduce the dose or stop.

Its place has shifted

Everolimus was developed before CDK4/6 inhibitors became standard. Today it is often considered later, after CDK4/6 inhibitors, and alongside newer options such as alpelisib or oral SERDs depending on test results.

Mouth sores can be largely prevented

Using a steroid mouthwash from the start makes a big difference and helps people stay on treatment.

Lung inflammation needs attention

It is usually mild and improves with a pause or steroids, but it must be reported promptly.

What this page cannot tell you

It cannot tell you where everolimus fits in your plan. Ask your oncologist about your options.

Everolimus affects metabolism and the immune system, so regular tests help keep treatment safe.

Blood sugar and cholesterol

Both are checked before and during treatment. Diet changes and medicines help if levels rise.

Infection sense

Wash hands regularly, avoid people with obvious infections where possible, and report fever promptly.

Vaccines

Live vaccines should be avoided. Ask your team about flu and other vaccines.

Several treatments are now available once hormone-sensitive metastatic cancer grows on a CDK4/6 inhibitor. Your oncologist weighs them together.

Test results

A PIK3CA mutation may point towards alpelisib, an ESR1 mutation towards an oral SERD, and a BRCA mutation towards a PARP inhibitor. Everolimus remains an option whatever these results show.

Side effects and health

Lung disease, diabetes and mouth problems may make everolimus less suitable, while other drugs have their own concerns.

Access and cost

Generic everolimus is available in India and may be more affordable than some newer options, which can influence the choice.