New Targeted Therapy Approval Represents Important Step Forward in Metastatic Breast Cancer Care
☑ Quick summary
The FDA granted accelerated approval to camizestrant, combined with a CDK4/6 inhibitor, for HR+/HER2- metastatic breast cancer with an ESR1 mutation. FCS helped develop the therapy from Phase 1 through Phase 3.
~40%
of patients have an ESR1 mutation after progression on aromatase inhibitor therapy
<5%
of patients have an ESR1 mutation at initial metastatic diagnosis
16.8 mo
median progression-free survival with camizestrant vs. 9.2 months in the control group
180+
clinical trials offered at nearly 30 FCS locations statewide
This approval will significantly impact the treatment paradigm for metastatic breast cancer.
✦ Key highlights
- • First-in-human Phase 1 trial conducted at the FCS Sarasota Drug Development Unit in 2019
- • FCS enrolled patients in the Phase 3 SERENA-6 trial
- • 315 randomized participants with an ESR1 mutation evaluated
- • Nearly doubled time without disease progression
- • Patients continue to access camizestrant through FCS clinical trials
✦ Did you know?
HR+/HER2- is the most common breast cancer subtype, accounting for roughly 70% of breast cancers in women. Most breast cancers in men are also hormone receptor-positive.
New Targeted Therapy Approval Represents Important Step Forward in Metastatic Breast Cancer Care
Florida Cancer Specialists & Research Institute plays a pivotal role leading to FDA approval
The FDA has granted accelerated approval to camizestrant in combination with a CDK4/6 inhibitor for certain patients with hormone receptor-positive, HER2-negative breast cancer whose tumors have developed an ESR1 mutation during treatment. An ESR1 mutation is a genetic change that can make some breast cancers resistant to hormone therapy over time. Together, these targeted treatments work in complementary ways — camizestrant, an oral SERD or targeted hormone therapy, blocks the estrogen signal that can help cancer cells grow, while the CDK4/6 inhibitor helps slow the cancer cells’ ability to divide and multiply.
Florida Cancer Specialists & Research Institute (FCS) played a pivotal role in the development of camizestrant. The Phase 1 first in human dose escalation trial (BRE321) was conducted in the FCS Sarasota Drug Development Unit (DDU) in 2019 and then later in FCS’ late phase trial division.
“This approval will significantly impact the treatment paradigm for metastatic breast cancer,” said FCS Medical Director of Drug Development Manish R. Patel, MD, who served as principal investigator for the Phase 1 trial. He noted, “While fewer than 5% of patients have an ESR1 mutation when metastatic breast cancer is first diagnosed, the mutation is found in nearly 40% of patients after their disease progresses on aromatase inhibitor therapy, underscoring the importance of testing and new targeted treatment options.”
FCS enrolled patients in the phase 3 SERENA-6 clinical trial which provided a broader and more definitive evaluation of whether camizestrant could delay cancer progression in patients with HR-positive, HER2-negative metastatic breast cancer. The trial evaluated 315 randomized participants who developed an ESR1 mutation. Patients who switched to camizestrant achieved a median progression-free survival of 16.0 to 16.8 months compared to 9.2 months in the control group, nearly doubling the time without disease progression.
Kim Vigal, MHA, FCS vice president of clinical research, said, “It is incredibly rewarding to see camizestrant reach FDA approval after our teams and patients participated in its development from Phase 1 through Phase 3.”
Vigal leads FCS’ clinical research program and designated ancillary departments and oversees the practice’s robust portfolio of more than 180 clinical trials across nearly 30 statewide locations that bring innovative treatment opportunities to patients in community settings close to home.
“This is the latest example of why access to clinical trials matters,” she said. “Patients who participate today help shape the treatment options of tomorrow. We are deeply grateful to our patients for their trust and their role in advancing cancer care.”
According to Chandni Patel, FCS associate director of clinical research, patients continue to access camizestrant through clinical trials as FCS expands its research efforts to explore the full potential of this promising therapy.
*The following FCS medical oncologists and hematologists served as principal investigators in the Phase 3 clinical trial: Maen Hussein, MD, Alpana Desai, MD, Liliana Bustamante, MD, Eric Harris, DO, R. Waide Weaver, MD, Fadi Kayali, MD, Lowell Hart, MD, FACP (retired), David Wright, MD, Sumithra Vattigunta, MD, FACP, Adewale Fawole, MD
Facts About Hormone Receptor-positive, HER2-negative Breast Cancer
- Hormone receptor-positive, HER2-negative (HR+/HER2-) breast cancer is the most common breast cancer subtype, accounting for roughly 70% of breast cancers in women.
- It has receptors for estrogen, progesterone or both, which can send signals that promote cancer cell growth, but does not have high levels of the HER2 protein.
- In the U.S., an estimated 322,000 women and 2,700 men will be diagnosed with invasive breast cancer in 2026.
- About 80% of breast cancers overall are hormone receptor-positive, and most breast cancers in men are also hormone receptor-positive.
