Advancements in Treating Advanced Breast Cancers

HER2 and metastatic breast cancers have new treatment options

/ Author:  / Reviewed by: Joseph V. Madia, MD

A great deal of exciting news has been released recently regarding novel drug combinations that extend the lives of patients living with advanced breast cancers. 

Here's a summary of what was presented at the 2011 CTRC-AACR San Antonio Breast Cancer Symposium, held December 6-10, 2011.

Arimidex and Faslodex combo effective against metastatic breast cancers

Researchers have found that combining two estrogen-blocking therapies - Arimidex (anastrozole) and Faslodex (fulvestrant) - extends the lives of post-menopausal women with metastatic hormone receptor positive breast cancers. The combination extended survival by more than six months, compared to standard treatment with Arimidex alone.

Both of these drugs are currently used to treat breast cancer. They have never been used in combination, though.

The phase III trial was led by University of California Irvine oncologist, Rita Mehta, M.D. These findings are particularly exciting because “these patients have not had a new treatment that gave them an overall survival benefit in more than a decade," Dr. Mehta said.

Afinitor + Aromasin extend progression-free survival

Combining Afinitor (everolimus) with the aromatase inhibitor Aromasin (exemestane) dramatically improves progression-free survival in post-menopausal women with metastatic breast cancer.

Those are the results of a study conducted by The University of Texas MD Anderson Cancer Center and led by Gabriel Hortobagyi, M.D., professor and chair of MD Anderson’s Department of Breast Medical Oncology.

The dual therapy extended progression-free survival to 7.4 months, compared to 3.2 months in those who took Aromasin alone.

Afinitor was first used to prevent rejection of organ transplants. It's now known to have cancer-fighting properties and is used to treat kidney and pancreatic cancers.

Findings from this study have also been published in the New England Journal of Medicine.

Adding Avastin to Herceptin improves survival slightly

Adding Avastin (bevacizumab) to Herceptin (trastuzumab) and chemotherapy extended progression-free survival in patients with recurrent or metastatic HER2-positive breast cancer.

These are the findings from AVEREL, a randomized, phase III trial.

After following participants for 26 months, investigator assessment and an independent review committee found the addition of Avastin improved survival by about three months.

Experimental drug holds promise as HER2 therapy

Researchers found that adding an experimental drug, pertuzumab, to a combination of Hercpetin (trastuzumab) and chemotherapy extended progression-free survival by some six months in patients with metastatic HER2-positive breast cancer. This is compared to survival times for patients who received the combination therapy with a placebo.

These are the findings of an international phase III trial, known as CLEOPATRA (CLinical Evaluation Of Pertuzumab And TRAstuzumab).

Pertuzumab is manufactured by Genetech

Senior researcher José Baselga, M.D., Ph.D., professor in the department of medicine at Harvard Medical School and associate director of the Massachusetts General Hospital Cancer Center, says these findings are very important.

“Most metastatic patients with HER2-positive breast cancer eventually stop responding to trastuzumab, so the fact that we now have an agent that can be added to current treatment to delay progression is very exciting," Dr. Baselga said.

Results  from this study are published in the New England Journal of Medicine.

Important advancements

The outlook for women with advanced breast cancer has improved significantly with these - the most meaningful advancements of late.