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Hormone Therapy

Giredestrant vs. Fulvestrant for Advanced Breast Cancer

Phase 3
Recruiting
Research Sponsored by Hoffmann-La Roche
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
Documented estrogen receptor-positive (ER+), HER2-negative (HER2-) tumor assessed locally on the most recent tumor biopsy (or archived tumor sample)
Confirmed ESR1 mutation status (ESR1m vs. ESR1nmd) in baseline circulating tumor DNA (ctDNA) through central laboratory testing
Must not have
Prior systemic therapy (e.g., prior chemotherapy, immunotherapy, or biologic therapy) for locally advanced unresectable or metastatic breast cancer
Advanced, symptomatic, visceral spread that is at risk of life-threatening complications in the short term
Timeline
Screening 3 weeks
Treatment Varies
Follow Up from randomization until end of follow-up (up to 5 years)
Awards & highlights
Pivotal Trial
No Placebo-Only Group

Summary

This trial is testing two drug combinations to treat a specific type of advanced breast cancer that no longer responds to standard hormone treatments. The goal is to see which combination works better by stopping the cancer cells from growing.

Who is the study for?
This trial is for adults with advanced breast cancer that's ER-positive, HER2-negative and has resisted previous endocrine therapy. They must have measurable disease or bone-only disease, be in good physical condition (ECOG PS 0-1), and pre/perimenopausal women and men need to use LHRH agonist therapy. People can't join if they've had certain prior treatments like SERDs, systemic therapies for advanced cancer, have serious heart or liver conditions, or are at immediate risk from their cancer.
What is being tested?
The study compares the effectiveness of Giredestrant versus Fulvestrant when each is combined with a CDK4/6 inhibitor (chosen by the investigator) in participants who have developed resistance to adjuvant endocrine therapy. It's a Phase III trial where patients are randomly assigned to either treatment group.
What are the potential side effects?
Possible side effects include hot flashes, nausea, injection site reactions from Fulvestrant; fatigue, diarrhea from CDK4/6 inhibitors; and potential unknown side effects from Giredestrant as it's newer.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below
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My tumor is estrogen receptor-positive and HER2-negative.
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My cancer has a known ESR1 mutation status from a blood test.
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My cancer can be measured by scans or is only in my bones.
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I haven't had any drug treatments for my advanced cancer.
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I am taking hormone therapy as required if I am a pre/perimenopausal woman or a man.
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My breast cancer cannot be cured with surgery or radiation.
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I can carry out all my daily activities without help.

Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:
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I have had treatments like chemotherapy for advanced breast cancer that cannot be surgically removed.
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My cancer has spread to vital organs and could cause serious problems soon.
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I have previously been treated with drugs targeting estrogen receptors.
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I have heart problems or a history of heart issues.
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I have a significant history of liver problems.

Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~from randomization until end of follow-up (up to 5 years)
This trial's timeline: 3 weeks for screening, Varies for treatment, and from randomization until end of follow-up (up to 5 years) for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.
Primary study objectives
Progression-Free Survival (PFS) in the ESR1 mutation (ESR1m) Subgroup
Secondary study objectives
Clinical Benefit Rate (CBR)
Confirmed Objective Response Rate (cORR)
Duration of Response (DOR)
+9 more

Awards & Highlights

Pivotal Trial
The final step before approval, pivotal trials feature drugs that have already shown basic safety & efficacy.
No Placebo-Only Group
All patients enrolled in this study will receive some form of active treatment.

Trial Design

2Treatment groups
Experimental Treatment
Active Control
Group I: Giredestrant + Investigator's Choice of CDK4/6iExperimental Treatment6 Interventions
Participants in the experimental arm will receive giredestrant plus the investigator's choice of CDK4/6 inhibitor (CDK4/6i): palbociclib, ribociclib, or abemaciclib.
Group II: Fulvestrant + Investigator's Choice of CDK4/6iActive Control6 Interventions
Participants in the control arm will receive fulvestrant plus the investigator's choice of CDK4/6 inhibitor (CDK4/6i): palbociclib, ribociclib, or abemaciclib.
Treatment
First Studied
Drug Approval Stage
How many patients have taken this drug
Ribociclib
2018
Completed Phase 3
~2420
Abemaciclib
2019
Completed Phase 2
~1890
Giredestrant
2019
Completed Phase 2
~300
Palbociclib
2017
Completed Phase 3
~3880
LHRH Agonist
2013
Completed Phase 2
~130

Research Highlights

Information in this section is not a recommendation. We encourage patients to speak with their healthcare team when evaluating any treatment decision.
Mechanism Of Action
Side Effect Profile
Prior Approvals
Other Research
Selective Estrogen Receptor Degraders (SERDs) like giredestrant work by binding to estrogen receptors on breast cancer cells, leading to receptor degradation and downregulation, which inhibits the cancer cells' growth driven by estrogen. This is crucial for patients with estrogen receptor-positive (ER+), HER2-negative breast cancer, as their tumors rely on estrogen signaling for proliferation. Other common treatments include aromatase inhibitors, which reduce estrogen production, and CDK4/6 inhibitors, which block proteins that promote cell division. These therapies are essential as they target the specific pathways that fuel cancer growth, offering more effective and personalized treatment options for patients.
A review of an unfavorable subset of breast cancer: estrogen receptor positive progesterone receptor negative.

Find a Location

Who is running the clinical trial?

Hoffmann-La RocheLead Sponsor
2,450 Previous Clinical Trials
1,094,494 Total Patients Enrolled
158 Trials studying Breast Cancer
90,582 Patients Enrolled for Breast Cancer
Clinical TrialsStudy DirectorHoffmann-La Roche
2,220 Previous Clinical Trials
894,344 Total Patients Enrolled
137 Trials studying Breast Cancer
71,304 Patients Enrolled for Breast Cancer
~677 spots leftby Jul 2026
Unbiased ResultsWe believe in providing patients with all the options.
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