A Phase 3 interventional study of Gedatolisib and Palbociclib in Breast Cancer, sponsored by Celcuity Inc. Active, not recruiting at 235 sites in 23 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-02-10.
Sponsored by Celcuity Inc · Phase 3, Interventional, and Treatment
This is a Phase 3, open-label, randomized, clinical trial evaluating the efficacy and safety of gedatolisib plus fulvestrant with or without palbociclib for the treatment of patients with locally advanced or metastatic HR+/HER2- breast cancer following progression on or after CDK4/6 and aromatase inhibitor therapy.
This is a Phase 3, open-label, randomized clinical trial evaluating the efficacy and safety of gedatolisib plus fulvestrant with or without palbociclib for the treatment of patients with advanced (inoperable) or metastatic Hormone Receptor Positive, Human Epidermal Growth Factor Receptor 2 Negative (HR+/HER2-) breast cancer following progression on or after CDK4/6 and aromatase inhibitor therapy. Gedatolisib is an intravenously administered pan-PI3K/mTOR inhibitor. Palbociclib is a CDK4/6 inhibitor. Fulvestrant is a selective estrogen receptor degrader (SERD). Subjects will be assessed for PIK3CA status and then randomized to treatment arms according to their confirmed PIK3CA mutation status.
14,825 studies on the registry are indexed under Breast Neoplasms; 3,319 are open to participants now.
This study's planned enrollment of 701 is above the median of 72 across 10,896 interventional studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Celcuity Inc is the lead sponsor of 5 studies on the registry; 3 are open to participants now.
Counted across the registry records on this site, refreshed daily.
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:
Known and untreated, or active, brain or
a. Subjects with previously treated central nervous system (CNS) may be enrolled in the study if they meet the following criteria: do not require supportive therapy with ; do not have seizures and do not exhibit uncontrolled neurological symptoms; stable disease confirmed by radiographic assessment within at least 4 weeks prior to enrollment
History of cardiovascular abnormalities such as: Congestive heart failure ( (NYHA) classification ≥ II within 6 months of study entry
Long syndrome, family history of idiopathic sudden death or congenital long QT syndrome, or any of the following:
Concurrent participation in another interventional clinical trial
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.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
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.
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.
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.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
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.
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
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.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
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.
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.
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.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
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.
Leptomeningeal disease
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
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.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Gedatolisib + Palbociclib + Fulvestrant
Drug: Gedatolisib · Drug: Palbociclib · Drug: Fulvestrant
Gedatolisib + Fulvestrant
Drug: Gedatolisib · Drug: Fulvestrant
Fulvestrant
Drug: Fulvestrant
Gedatolisib + Palbociclib + Fulvestrant
Drug: Gedatolisib · Drug: Palbociclib · Drug: Fulvestrant
Alpelisib + Fulvestrant
Drug: Fulvestrant · Drug: Alpelisib
Gedatolisib + Fulvestrant
Drug: Gedatolisib · Drug: Fulvestrant
Gedatolisib 180 mg IV given weekly for 3 weeks (Days 1, 8, 15) followed by 1 week off
Also known as: PF-05212384, PKI-587
Palbociclib 125 mg PO given daily for 3 weeks (21 days), followed by 1 week off
Also known as: IBRANCE, PD-0332991
Fulvestrant 500 mg IM (2 × 5 mL injections) given every 2 weeks during Cycle 1 (Days 1 and 15), then every 4 weeks beginning with Cycle 2 Day 1
Also known as: Faslodex
Alpelisib 300 mg PO (2 × 150 mg tablets) given daily for 4 weeks (28 days)
Also known as: Piqray, Vijoice, BYL719
Progression Free Survival (PFS) in Patients with PIK3CA WT and PIK3CA MT Breast Cancer
PFS is defined as the time from randomization to death or the first documented progression, whichever occurs first, confirmed by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 criteria, as determined based on blinded independent central review (BICR)
Time frame: Approximately 48 months
Overall Survival (OS) in Patients with PIK3CA WT and PIK3CA MT Breast Cancer
OS is defined as the length of time from randomization until the date of death from any cause method, where PFS is defined as the time from randomization to death or the first documented progression, whichever occurs first, confirmed by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 criteria, as determined based on blinded independent central review (BICR)
Time frame: From date of randomization to the date of death due to any cause, up to approximately 48 months
Overall Response Rate (ORR) in Patients with PIK3CA WT and PIK3CA MT Breast Cancer
Percentage of subjects who achieved an objective response according to RECIST v1.1 criteria (complete response \[CR\] or partial response \[PR\]) as assessed by BICR)
Time frame: Up to approximately 48 months
Duration of Response (DOR) in Patients with PIK3CA WT and PIK3CA MT Breast Cancer
Time from the assessment of initial response (PR or better) to death or first documented disease progression as assessed by BICR, whichever occurs first
Time frame: Up to approximately 48 months
Time to Response (TTR) in Patients with PIK3CA WT and PIK3CA MT Breast Cancer
Time form randomization to the first assessment of PR or better as assessed by BICR, whichever comes first
Time frame: Up to approximately 48 months
Clinical Benefit Rate (CBR) in Patients with PIK3CA WT and PIK3CA MT Breast Cancer
Percentage of subjects with CR, PR, or stable disease (SD) \>24 weeks as assessed by BICR
Time frame: Up to approximately 48 months
Quality of Life (QOL)Functional Assessment of Cancer Therapy - Breast Trial Outcome Index (FACT-B TOI) Questions in Patients with PIK3CA WT and PIK3CA MT Breast Cancer
The FACT-B TOI is an abbreviated (24-item) version of the full FACT-B which focuses only on the patient's Physical Well-being (PWB), Functional Well-being (FWB), and Breast Cancer Subscale (BCS) components using a 5-level scale, (Not at all, A little bit, Some-what, Quite a bit, Very much).
Time frame: From baseline to 30 Day Safety Follow-up
Quality of Life (QOL) NCCN-FACT Breast Symptom Index -16 (NFBSI-16) in Patients with PIK3CA WT and PIK3CA MT Breast Cancer
NCCN-FACT is derived from the FACT-B and only 4 additional items will be administered to enable optional scoring of the NFBSI subscales and total score using a 5-level scale (Not at all, A little bit, Some-what, Quite a bit, Very much).
Time frame: From baseline to 30 Day Safety Follow-up
Patient-Reported Outcomes in Patients with PIK3CA WT and PIK3CA MT Breast Cancer
Patient-Reported Outcomes Measurement Information System (PROMIS®) Short Form v2.0 - Physical Function 8c using a 5-level scale (Without any difficulty, With a little difficulty, With some difficulty, With much difficulty, Unable to do)
Time frame: From baseline to 30 Day Safety Follow-up
EuroQol 5 in Patients with PIK3CA WT and PIK3CA MT Breast Cancer
EuroQol 5 Dimension 5 Level (EQ-5D-5L) - This is a 5 question, self-administered visual analog scale (VAS) where patients use 0 (worst health) to 100 (best health) to indicate how they view their health.
Time frame: From baseline to 30 Day Safety Follow-up
Adverse Events
Safety and tolerability will be evaluated by review of type, incidence, severity (as graded by the National Cancer Institute Common Terminology Criteria for Adverse Events \[NCI CTCAE\] v5.0), seriousness, and relationship to study medications of adverse events (AEs) and any laboratory abnormalities
Time frame: Up to approximately 48 months
Showing the first 100 of 235 sites across 23 countries. Choose a country and city above to see the rest.
This study is active, not recruiting, as verified in Feb 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Gedatolisib
Celcuity Inc