Emerging Treatments for Metastatic Breast Cancer Shared at SABCS 2017

Researchers shared encouraging results in clinical trials focused on advanced breast cancer

Researchers at the San Antonio Breast Cancer Symposium shared encouraging findings from clinical trials that are advancing treatment for metastatic breast cancer. Here we summarize three key studies highlighting new targeted therapies for advanced breast cancer.

CDK4/6 Inhibitors Shown to Benefit Young and Old with Advanced Breast Cancer

CDK 4/6 inhibitors have shown a dramatic benefit for many women with advanced ER-positive breast cancer when given with an aromatase inhibitor. At SABCS, researchers shared findings from the MONALEESA 7 trial, which is the first to test a CDK4/6 inhibitor with tamoxifen in younger (pre- or peri-menopausal) women.

Study investigators reported that ribociclib (Kisqali) significantly improved progression free survival (23.8 months vs. 13 months with the placebo). Follow up on the study continues and will be important in determining the benefit of ribociclib in this patient group. View a short video with Debu Tripathy, MD, lead investigator on the trial.

In a separate study, a pooled analysis of clinical trials with three CDK 4/6 inhibitors, demonstrated a similar benefit of CDK 4/6 inhibitor therapy with aromatase inhibitors in women 65 and older with ER-positive advanced breast cancer.

The study is limited by the small numbers of older patients enrolled in the clinical trials, but offers promise that these new agents will benefit patients across the age spectrum on either an aromatase inhibitor or tamoxifen. You can read more about the study in the ASCO Post.

New PARP Inhibitor Extends Survival and Quality of Life for Patients with BRCA-driven Advanced Breast Cancer

PARP inhibitors are a class of drugs that have been shown to be an effective treatment for ovarian cancers, particularly those harboring mutations in the BRCA gene. Clinical trials in BRCA-driven breast cancers, including triple negative breast cancer, have shown promise.

In a report from the phase III EMBRACA trial, talazoparib, a new PARP formulation with dual activity against the PARP protein and DNA repair, was reported to improved progression free survival (8.6 months vs. 5.3 months) and overall response (62.6% vs. 27.2%) when compared to standard chemotherapy.

The benefit was similar in ER-positive as well as triple negative breast cancers. The study authors also reported a significant delay in clinical deterioration from 6.3 months in patients receiving the standard of care to 24.3 months in patients receiving talazoparib. Read more about the study here.

Read more of our coverage from SABCS here.