A Phase 3 interventional study of Giredestrant and Fulvestrant in Estrogen Receptor-Positive, HER2-Negative Advanced Breast Cancer, sponsored by Hoffmann-La Roche. Active, not recruiting at 311 sites in 37 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-14.
Sponsored by Hoffmann-La Roche · Phase 3, Interventional, and Treatment
Among 16 studies testing giredestrant in Breast Neoplasms — 4 open to participants now, 12 under way, 7 of them phase 3. giredestrant · Breast Neoplasms.
Among the 16 studies testing giredestrant in Breast Neoplasms, this one is the 3rd largest by planned enrollment, is one of 2 that started in 2023, is one of 7 in phase 3, reaches primary completion later than 7 of the 11 other live ones, and was the 12th registered.
14,825 studies on the registry are indexed under Breast Neoplasms; 3,319 are open to participants now.
Browse Breast Neoplasms studies →4 of the 16 studies testing giredestrant in Breast Neoplasms are open now, in 8 countries. Recruiting first, the newest first:
Hoffmann-La Roche · Sites in Canada
Genentech, Inc. · Sites in United States
Hoffmann-La Roche · Sites in United States, Argentina, Brazil and 4 more countries
Fondazione Oncotech · Sites in Italy
By country, each count listing its studies:
No approval found in the FDA or EMA files read. How studies give it is on its page →
Of the 2,400 Breast Neoplasms studies recruiting now, 1,572 (66%) set no upper age limit and 591 (25%) stop at 75 or younger; 103 take children under 18; 214 take healthy volunteers.
This study: 18 Years and older · all sexes · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
On this site’s reading of the record, giredestrant is the treatment under test here. Read study by study →
16 studies; the count open now beside each. This study's row is marked.
First in 2017; this study’s year is marked. 2 started in 2023.
This study's planned enrollment of 1,050 is above the median of 72 across 10,896 interventional studies indexed under Breast Neoplasms.
Median enrollment 302 across the 16 interventional studies. Of the 4 that completed or were terminated, 3 (75%) have results posted.
This tab as a report to print or save as PDF → With an account.
12 of 16 have an industry lead sponsor. The 5 most frequent:
Hoffmann-La Roche is the lead sponsor of 2,101 studies on the registry; 87 are open to participants now.
Of its 330 completed or terminated interventional studies of FDA-regulated products, 248 (75%) have results posted.
179 studies in Breast Neoplasms by Hoffmann-La Roche: 13 open now, 21 under way, 11 of them phase 3. Of 154 finished, 103 (67%) have results posted.
Among the 179 studies in Breast Neoplasms by Hoffmann-La Roche, this one is the 16th largest by planned enrollment of the 134 interventional ones that give a count, is one of 5 that started in 2023, is one of 54 in phase 3, reaches primary completion later than 10 of the 20 other live ones, and was the 169th registered.
Hoffmann-La Roche’s Breast Neoplasms studies by the year they started, since 1998.
2 of the studies testing giredestrant in Breast Neoplasms that are under way reach primary completion within a year, 0 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT03332797Genentech, Inc.A Study of GDC-9545 Alone or in Combination With Palbociclib and/or Luteinizing Hormone-Releasing Hormone (LHRH) Agonist in Locally Advanced or Metastatic Estrogen Receptor-Positive Breast Cancer | 2027-07-31 |
| NCT07054190Hoffmann-La RocheA Study to Test Inavolisib Treatments in Participants With Early-Stage, PIK3CA-Mutated Breast Cancer | 2027-07-31 |
Among the 16 studies testing giredestrant in Breast Neoplasms, from their registry updates:
Among Hoffmann-La Roche’s 179 in Breast Neoplasms:
This tab as a report to print or save as PDF → With an account.
This is a Phase III, randomized, open-label multicenter study that will evaluate the efficacy and safety of giredestrant compared with fulvestrant, both in combination with the investigator's choice of a CDK4/6 inhibitor (palbociclib, ribociclib or abemaciclib), in participants with estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer who have developed resistance to adjuvant endocrine therapy.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HER2
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Adjuvant and neoadjuvant
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Relapsed and refractory
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Measurable disease
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
RECIST
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants in the experimental arm will receive giredestrant plus the investigator's choice of CDK4/6 inhibitor (CDK4/6i): palbociclib, ribociclib, or abemaciclib.
Drug: Giredestrant · Drug: Abemaciclib · Drug: Palbociclib · Drug: Ribociclib · Drug: LHRH Agonist · Diagnostic Test: FoundationOne Liquid CDx Assay (F1LCDx)
Participants in the control arm will receive fulvestrant plus the investigator's choice of CDK4/6 inhibitor (CDK4/6i): palbociclib, ribociclib, or abemaciclib.
Drug: Fulvestrant · Drug: Abemaciclib · Drug: Palbociclib · Drug: Ribociclib · Drug: LHRH Agonist · Diagnostic Test: FoundationOne Liquid CDx Assay (F1LCDx)
Giredestrant 30 milligrams (mg) orally (PO) once a day (QD) on Days 1-28 of each 28-day cycle until progressive disease (PD) or unacceptable toxicity.
Also known as: RO7197597, RG6171, GDC-9545
Fulvestrant 500 mg intramuscularly (IM) on Days 1 and 15 of Cycle 1 and on Day 1 of each subsequent 28-day cycle until PD or unacceptable toxicity.
If chosen by the investigator as the CDK4/6i, participants will receive abemaciclib 150 mg PO twice per day (BID) on Days 1-28 of each 28-day cycle until PD or unacceptable toxicity.
If chosen by the investigator as the CDK4/6i, participants will receive palbociclib 125 mg PO QD on Days 1-21 of each 28-day cycle until PD or unacceptable toxicity.
If chosen by the investigator as the CDK4/6i, participants will receive ribociclib 600 mg PO QD on Days 1-21 of each 28-day cycle until PD or unacceptable toxicity.
Only pre/perimenopausal female participants and male participants will receive a luteinizing hormone-releasing hormone (LHRH) agonist locally approved for use in breast cancer on Day 1 of each 28-day treatment cycle.
F1LCDx is a next-generation sequencing (NGS)-based in vitro diagnostic test that detects and analyses genomic alterations in circulating cell-free DNA (cfDNA) isolated from plasma derived from the anti-coagulated peripheral whole blood of cancer patients. It will be used to determine the eligibility of participants requiring confirmation of ESR1 mutation status (mutation detected \[ESR1m\] vs. no mutation detected \[ESR1nmd\]).
Also known as: F1LCDx
Progression-Free Survival (PFS) in the ESR1 mutation (ESR1m) Subgroup
PFS is defined as the time from randomization to the first occurrence of PD, as determined by the investigator according to Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1), or death from any cause during the study.
Time frame: From randomization to first occurrence of progressive disease (PD) or death (up to 5 years)
PFS in the Full Analysis Set (FAS) Population
Time frame: From randomization to first occurrence of PD or death (up to 5 years)
PFS in the ESR1 no-mutation-detected (ESR1nmd) Subgroup
Time frame: From randomization to first occurrence of PD or death (up to 5 years)
Overall Survival (OS)
OS is defined as the time from randomization to death from any cause. It will be analyzed in the FAS and in the ESR1m and ESR1nmd subgroups.
Time frame: From randomization until death from any cause (up to 5 years)
Confirmed Objective Response Rate (cORR)
The cORR is defined as the percentage of participants with a complete response (CR) or partial response (PR) on two consecutive occasions at least 4 weeks apart, as determined by the investigator according to RECIST v1.1. It will be analyzed in the FAS and in the ESR1m and ESR1nmd subgroups.
Time frame: From randomization until treatment discontinuation (up to 5 years)
Duration of Response (DOR)
DOR is defined as the time from the first occurrence of a documented objective response to PD, as determined by the investigator according to RECIST v1.1, or death from any cause (whichever occurs first). It will be analyzed in the FAS and in the ESR1m and ESR1nmd subgroups.
Time frame: From the first occurrence of a documented objective response to PD or death (up to 5 years)
Clinical Benefit Rate (CBR)
The CBR is defined as the percentage of participants with stable disease for at least (≥)24 weeks or a CR or PR, as determined by the investigator according to RECIST v1.1. It will be analyzed in the FAS and in the ESR1m and ESR1nmd subgroups.
Time frame: From randomization until treatment discontinuation (up to 5 years)
Time to Chemotherapy
Time to chemotherapy is defined as the time from randomization until the start date of the first chemotherapy or death from any cause (whichever occurs first). It will be analyzed in the FAS and in the ESR1m and ESR1nmd subgroups.
Time frame: From randomization until the start of chemotherapy or death (up to 5 years)
Time to Confirmed Deterioration (TTCD) in Pain Severity
TTCD in pain severity is defined as the time from randomization to the first documentation of ≥2-point increase from baseline on the "worst pain" item score of the Brief Pain Inventory-Short Form (BPI-SF). It will be analyzed in the FAS and in the ESR1m and ESR1nmd subgroups.
Time frame: From randomization until end of follow-up (up to 5 years)
TTCD in Pain Presence and Interference
TTCD in pain presence and interference is defined as the time from randomization to the first documentation of ≥10-point increase in pain score, as determined using the European Organisation for Research and Treatment of Cancer Quality of Life-Core 30 (EORTC QLQ-C30) questionnaire. It will be analyzed in the FAS and in the ESR1m and ESR1nmd subgroups.
Time frame: From randomization until end of follow-up (up to 5 years)
TTCD in Physical Functioning
TTCD in physical functioning (PF) is defined as the time from randomization to the first documentation of ≥10-point decrease in PF score, as determined using the EORTC QLQ-C30 questionnaire. It will be analyzed in the FAS and in the ESR1m and ESR1nmd subgroups.
Time frame: From randomization until end of follow-up (up to 5 years)
TTCD in Role Functioning
TTCD in role functioning (RF) is defined as the time from randomization to the first documentation of ≥10-point decrease in RF score, as determined using the EORTC QLQ-C30 questionnaire. It will be analyzed in the FAS and in the ESR1m and ESR1nmd subgroups.
Time frame: From randomization until end of follow-up (up to 5 years)
TTCD in Global Health Status/Quality of Life
TTCD in in Global Health Status/Quality of Life (GHS/QoL) is defined as the time from randomization to the first documentation of ≥10-point decrease in GHS/QoL score, as determined using the EORTC QLQ-C30 questionnaire. It will be analyzed in the FAS and in the ESR1m and ESR1nmd subgroups.
Time frame: From randomization until end of follow-up (up to 5 years)
Incidence and Severity of Adverse Events
Incidence will be reported as the number of participants with at least one adverse event, with severity determined according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 5 (NCI CTCAE v5.0).
Time frame: From Baseline until 28 days after the final dose of study treatment (up to 5 years)
Number of Participants with Vital Sign Abnormalities Over the Course of the Study
Vital signs include respiratory rate, pulse rate, systolic and diastolic blood pressure, and temperature.
Time frame: From Baseline until 28 days after the final dose of study treatment (up to 5 years)
Number of Participants with Clinical Laboratory Test Abnormalities for Hematology and Biochemistry Parameters Over the Course of the Study
Time frame: From Baseline until 28 days after the final dose of study treatment (up to 5 years)
Showing the first 100 of 311 sites across 37 countries. Choose a country and city above to see the rest.
Plan to share: Yes — For eligible studies, qualified researchers may request access to individual patient level clinical data. See Roche's commitment to transparency of clinical study information here: https://go.roche.com/data_sharing
Started Dec 2023 (actual). Primary completion is estimated for Apr 2028, 52 months after the start.
Of 272 industry-sponsored phase 3 interventional studies under Breast Neoplasms, half reached primary completion within 40 months of starting (the median), counting those still running; a quarter within 28 and three quarters within 63. This study's planned 52 months is above that.
Counting every sponsor, half of 600 studies reached it within 59 months; a quarter within 36 and three quarters within 96.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Giredestrant