Seeking better treatments for people with ER+/HER- breast cancer

Friday, April 25, 2025

Breast cancer isn’t just one disease, it comes in different forms. Each form of the disease has its own challenges and treatment options. One of the most common types is estrogen receptor-positive (ER+) human epidermal growth factor receptor 2 negative (HER2-) early-stage breast cancer.

Many people with this type of cancer are successfully treated with surgery, radiation and endocrine therapy, and sometimes with chemotherapy. However, the cancer eventually comes back in some people.

A new phase III clinical trial enrolling patients at Providence Cancer Institute of Oregon is investigating whether a medication called camizestrant can improve outcomes compared to standard endocrine therapy.

If successful, this study could offer a more effective way to reduce the risk of cancer coming back.

Study details

This study focuses on patients with early-stage ER+/HER2- breast cancer who are at intermediate-high or high risk for recurrence. Participants must have already completed their initial treatment, including surgery and possibly chemotherapy. Researchers are comparing camizestrant to standard endocrine therapy to see if it provides better protection against cancer returning. Some patients may also take abemaciclib, another cancer treatment approved by the Food and Drug Administration.

Camizestrant is an investigational oral selective estrogen receptor degrader (SERD). Preclinical studies have shown that camizestrant effectively degrades estrogen receptors, inhibiting the growth of tumor cells. It has shown strong antitumor activity as a standalone treatment and in combination with other therapies.

The planned treatment period for participants is up to seven years, with follow-ups continuing for 10 years.

Throughout the study, researchers will measure how well camizestrant prevents invasive breast cancer from coming back, along with overall survival, safety and patients’ quality of life. If successful, this study could lead to improved treatment options for patients at risk of recurrence.

Where to get more information

Providence Cancer Institute is currently enrolling patients in this study.  Alison Conlin, M.D., MPH, medical director, Providence Breast Cancer Medical Program and High-Risk Breast Cancer Clinic, is the principal investigator. 

Get more details about the study:

A Phase III, Open-Label, Randomized Study to Assess the Efficacy and Safety of Camizestrant Versus Standard Endocrine Therapy

To refer a patient:

Call 503-215-1979
Send an email

Early-stage ER+/HER2- breast cancer: Study for premenopausal women

A new study for young people with early-stage, ER+/HER2- breast cancer is looking at whether chemotherapy with ovarian suppression and hormone therapy leads to better long-term survival compared to ovarian suppression and hormone therapy alone.

The study focuses on women who are premenopausal and have a specific range of scores on a test that predicts cancer recurrence risk.

Providence Cancer Institute is currently enrolling patients in this study.

Ovarian function suppression explained

Breast cancer in younger people can be more aggressive, and current treatments don’t always provide the same long-term benefits as they do for those over 40. There is a pressing need for advancements in treatment options for this group of people.

One treatment is ovarian function suppression. This approach has been used for over a century to reduce estrogen production by the ovaries. Estrogen can promote the growth of certain breast cancers. Medications, surgery or radiation therapy are some methods used to suppress the production of estrogen.

Past studies comparing ovarian function suppression to chemotherapy have shown mixed results, especially before newer cancer medications became available. Some earlier research suggested that blocking ovarian function could be as effective as chemotherapy, particularly for people under 40. However, these studies were done before advanced tumor genetic testing and newer chemotherapy drugs were widely used.

Study design

The goal of this two-arm study is to provide results that help doctors make better treatment decisions for people with early-stage ER+/HER2- breast cancer. The two arms include:

Arm 1: Ovarian function suppression plus aromatase inhibitor
An aromatase inhibitor is a type of hormone therapy. The aromatase inhibitor will be given with a GnRH agonist (gonadotropin releasing hormone) for five years.

Arm 2: Chemotherapy after surgery plus ovarian function suppression plus aromatase inhibitor
Chemotherapy is by investigator's choice followed by an aromatase inhibitor given with an GnRH agonist for five years.