A Phase 2 interventional study of Tazemetostat in Malignant Rhabdoid Tumors (MRT), Rhabdoid Tumors of the Kidney (RTK) and Atypical Teratoid Rhabdoid Tumors (ATRT), sponsored by Epizyme, Inc.. Completed at 32 sites in 9 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-06-22.
Sponsored by Epizyme, Inc. (part of Ipsen) · Phase 2, Interventional, and Treatment
This study will include participants with various types of cancer known as soft-tissue sarcomas.
Tissues that can be affected by soft tissue sarcomas include fat, muscle, blood vessels, deep skin tissues, tendons and ligaments.
Soft tissue cancers are rare and can occur almost anywhere in the body.
Part 1 of this trial will study the safety and the level that adverse effects of the study drug tazemetostat in combination with doxorubicin (current front line treatment) can be tolerated (known as tolerability).
It is also designed to establish a recommended study drug dosage for the next part of the study.
Part 2 will evaluate and compare how long participants live without their disease getting worse when receiving the study drug plus doxorubicin versus doxorubicin plus placebo (dummy treatment).
This is a Phase II, multicenter, open-label, single arm, 2-stage study of tazemetostat 800 mg BID (twice daily) and 1600 mg QD (once daily). Subjects will be screened for eligibility within 21 days of the planned date of the first dose of tazemetostat and enrolled into one of 8 cohorts:
Cohort using tazemetostat 800 mg BID
Cohort using tazemetostat 1600 mg QD
Participants will be dosed in continuous 28-day cycles. (Note: if treatment with study drug is discontinued prior to completing 2 years, subjects will be followed for a maximum duration of 2 years from start of study drug dosing.) Response assessment will be performed every 8 weeks while on study.
Treatment with tazemetostat will continue until disease progression, unacceptable toxicity or withdrawal of consent, or termination of the study.
133 studies on the registry are indexed under Sarcoma, Synovial; 29 are open to participants now.
This study's enrollment of 267 is above the median of 46 across 117 interventional studies indexed under Sarcoma, Synovial.
Browse Sarcoma, Synovial studies →Epizyme, Inc. is the lead sponsor of 21 studies on the registry; none are open to participants now.
Of its 12 completed or terminated interventional studies of FDA-regulated products, 9 (75%) have results posted.
First submitted before Epizyme, Inc. became part of Ipsen.
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.
Has a :
That is after treatment with an approved therapy(ies), defined as or non-resectable, locally advanced disease that has previously been treated with and progressed following approved therapy(ies) (Cohort 2)
For Cohort 6 (subjects with ES undergoing optional tumor biopsy) only:
Prior anti-cancer therapy(ies), if applicable, must be completed according to the criteria below:
Female subjects of must:
Male subjects with a female partner of childbearing potential must:
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.
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.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
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.
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 US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
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.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
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.
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 drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
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.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
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.
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.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
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.
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.
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.
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.
CTCAE grade
The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
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.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
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.
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.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
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.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
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.
All cohorts will receive 800 mg oral Tazemetostat twice a day in continuous 28-day cycles.
Drug: Tazemetostat
Tazemetostat (EPZ-6438) is a selective small molecule inhibitor of the histone-lysine methyltransferase EZH2 gene
Also known as: EPZ-6438, E7438, IPN60200
Cohorts 1, 3, 4, 5, 6 and 7: Objective Response Rate (ORR)
ORR was defined as percentage of participants who achieved a confirmed complete response (CR) or partial response (PR) based on the investigator review from start of treatment until progressive disease (PD) or start of subsequent anti-cancer therapy or cancer-related surgery, whichever was earlier, as per response assessment in neuro-oncology (RANO) criteria for primary brain tumors or response evaluation criteria in solid tumors (RECIST) version (v) 1.1 criteria for all other solid tumors. CR was defined as disappearance of all target and non-target lesions. Any pathological lymph nodes must be \<10 millimeter (mm) in short axis. PR was defined as at least 30% decrease in sum of diameters of target lesions, taking as a reference, baseline sum of diameters. PD was defined as at least a 20% increase in sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since treatment started. In addition, sum must have an absolute increase from nadir of 5 mm.
Time frame: Tumor assessment performed at screening and every 8 weeks beginning at Cycle 3 Day 1, until disease progression or the start of subsequent anti-cancer therapy, whichever occurred first, up to 5.75 years (cycle duration: 28 days)
Cohort 2: Progression-Free Survival (PFS) Rate at 16 Weeks of Treatment With Tazemetostat
PFS was defined as the interval of time between the date of the first dose of study treatment and the earliest date of PD or death due to any cause, whichever comes first, as per RECIST v 1.1 criteria. PFS rate at 16 week was estimated. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since the treatment started. In addition, the sum must have an absolute increase from nadir of 5 mm.
Time frame: At 16 Weeks
Cohort 8: Number of Participants With Treatment-emergent Adverse Events (TEAEs) and Treatment-emergent Serious Adverse Events (TESAEs)
An AE was defined as any untoward medical occurrence in a participant or clinical investigation participant administered a medicinal product and which did not necessarily have a causal relationship with this treatment. An SAE was defined as any untoward medical occurrence that, at any dose: resulted in death, was life threatening, required hospitalization or prolongation of existing hospitalization, resulted in disability/incapacity, was a congenital anomaly/birth defect or was medically significant. TEAEs were defined as AEs if one of the following conditions met: emerged after the time of first dose administration, having been absent prior to the first dose; re-emerged, having been present but stopped prior to the time of first dose administration; worsened in severity after the time of first dose administration relative to the pretreatment state, when the AE was continuous.
Time frame: From first dose of study treatment (Day 1) up to 30 days after the last dose of study treatment, approximately 148 weeks
All Cohorts: Duration of Response (DOR)
DOR was defined as time from the first documented evidence of CR or PR based on investigator review to the time of first documented PD or death due to any cause, whichever came first, as per RECIST v 1.1 criteria. CR was defined as disappearance of all target and non-target lesions. Any pathological lymph nodes must be \<10 mm in the short axis. PR was defined as at least 30% decrease in sum of diameters of target lesions, taking as a reference, baseline sum of diameters. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since the treatment started. In addition, the sum must have an absolute increase from nadir of 5 mm.
Time frame: Tumor assessment performed at screening and every 8 weeks beginning at Cycle 3 Day 1, until disease progression or the start of subsequent anti-cancer therapy, whichever occurred first, up to 5.75 years (cycle duration 28 days)
All Cohorts: Progression-Free Survival (PFS)
PFS was defined as the interval of time between the date of the first dose of study treatment and the earliest date of PD or death due to any cause, whichever comes first, as per RECIST v 1.1 criteria. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since the treatment started. In addition, the sum must have an absolute increase from nadir of 5 mm.
Time frame: Tumor assessment performed at screening and every 8 weeks beginning at Cycle 3 Day 1, until disease progression or the start of subsequent anti-cancer therapy, whichever occurred first, up to 5.75 years (cycle duration 28 days)
All Cohorts: Progression-Free Survival (PFS) Rate at Weeks 24, 32 and 56
PFS was defined as the interval of time between the date of the first dose of study treatment and the earliest date of PD or death due to any cause, whichever comes first, as per RECIST v 1.1 criteria. PFS rate at 24, 32 and 56 weeks were estimated. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since the treatment started. In addition, the sum must have an absolute increase from nadir of 5 mm. Estimates were calculated with Kaplan-Meier analysis and 95% CIs using the complementary log-log transformation.
Time frame: At Weeks 24, 32 and 56
All Cohorts: Overall Survival (OS)
OS was defined as the interval of time between the date of the first dose of study treatment and the date of death due to any cause.
Time frame: Tumor assessment performed at screening and every 8 weeks beginning at Cycle 3 Day 1, until disease progression or the start of subsequent anti-cancer therapy, whichever occurred first, up to 5.75 years (cycle duration: 28 days)
All Cohorts: Overall Survival (OS) Rate at Weeks 24, 32 and 56
OS was defined as the interval of time between the date of the first dose of study treatment and the date of death due to any cause. OS rate at 24, 32 and 56 weeks were estimated. Estimates were calculated with Kaplan-Meier analysis and 95% CIs using the complementary log-log transformation.
Time frame: At Weeks 24, 32 and 56
All Cohorts: Disease Control Rate (DCR) at Weeks 12, 24, 32 and 48
DCR was defined as the percentage of participants who achieved a confirmed response (CR or PR, as per RECIST v 1.1 criteria) or who have SD lasting at least 32 weeks from the start of treatment until disease progression or the start of subsequent anti-cancer therapy. CR was defined as disappearance of all target and non-target lesions. Any pathological lymph nodes must be \<10 mm in the short axis. PR was defined as at least 30% decrease in sum of diameters of target lesions, taking as a reference, baseline sum of diameters. SD was defined neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for progressive disease.
Time frame: At Weeks 12, 24, 32 and 48
Cohorts 2 and 8: Objective Response Rate (ORR)
ORR was defined as percentage of participants who achieved a confirmed CR or PR based on investigator assessment from start of treatment until PD or start of subsequent anti-cancer therapy or cancer-related surgery, whichever was earlier, as per RANO criteria for primary brain tumors or RECIST v 1.1 criteria for all other solid tumors. CR was defined as disappearance of all target and non-target lesions. Any pathological lymph nodes must be \<10 mm in the short axis. PR was defined as at least 30% decrease in sum of diameters of target lesions, taking as a reference, baseline sum of diameters. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since the treatment started. In addition, the sum must have an absolute increase from nadir of 5 mm.
Time frame: Tumor assessment performed at screening and every 8 weeks beginning at Cycle 3 Day 1, until disease progression or the start of subsequent anti-cancer therapy, whichever occurred first, up to 5.75 years (cycle duration: 28 days)
This Phase II, open-label study was conducted at 28 sites in 9 countries (Australia, Belgium, Canada, France, Germany, Italy, Taiwan, United Kingdom, and United States) from 22 December 2015 to 26 February 2024.
| Milestone | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 |
|---|---|---|---|---|---|---|---|---|
| Started | 32 | 33 | 32 | 14 | 62 | 69 | 18 | 7 |
| Completed | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Not completed | 32 | 33 | 32 | 14 | 62 | 69 | 18 | 7 |
| Withdrew: Participant enrolled in rollover study | 0 | 0 | 1 | 0 | 1 | 1 | 1 | 0 |
| Withdrew: Disease progression - radiological | 21 | 26 | 22 | 11 | 46 | 52 | 7 | 5 |
| Withdrew: Disease progression - clinical | 3 | 5 | 4 | 2 | 6 | 6 | 5 | 1 |
| Withdrew: Death | 6 | 0 | 3 | 1 | 4 | 1 | 0 | 0 |
| Withdrew: Unacceptable toxicity (related to study treatment) | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 |
| Withdrew: Adverse event (not related to study treatment) | 1 | 0 | 0 | 0 | 0 | 2 | 0 | 0 |
| Withdrew: Non-compliance | 0 | 1 | 0 | 0 | 0 | 1 | 1 | 0 |
| Withdrew: Participant refused further study treatment | 0 | 1 | 1 | 0 | 2 | 2 | 2 | 1 |
| Withdrew: Investigator discretion | 1 | 0 | 1 | 0 | 1 | 1 | 1 | 0 |
| Withdrew: Other | 0 | 0 | 0 | 0 | 2 | 2 | 1 | 0 |
ORR was defined as percentage of participants who achieved a confirmed complete response (CR) or partial response (PR) based on the investigator review from start of treatment until progressive disease (PD) or start of subsequent anti-cancer therapy or cancer-related surgery, whichever was earlier, as per response assessment in neuro-oncology (RANO) criteria for primary brain tumors or response evaluation criteria in solid tumors (RECIST) version (v) 1.1 criteria for all other solid tumors. CR was defined as disappearance of all target and non-target lesions. Any pathological lymph nodes must be \<10 millimeter (mm) in short axis. PR was defined as at least 30% decrease in sum of diameters of target lesions, taking as a reference, baseline sum of diameters. PD was defined as at least a 20% increase in sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since treatment started. In addition, sum must have an absolute increase from nadir of 5 mm.
| Percentage of participants | Rhabdoid Tumors: Cohort 1 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 |
|---|---|---|---|---|---|---|
| Cohorts 1, 3, 4, 5, 6 and 7: Objective Response Rate (ORR) | 9.4 (2.0 to 25.0) | 9.4 (2.0 to 25.0) | 0.0 (0.0 to 23.2) | 16.1 (8.0 to 27.7) | 15.9 (8.2 to 26.7) | 5.6 (0.1 to 27.3) |
PFS was defined as the interval of time between the date of the first dose of study treatment and the earliest date of PD or death due to any cause, whichever comes first, as per RECIST v 1.1 criteria. PFS rate at 16 week was estimated. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since the treatment started. In addition, the sum must have an absolute increase from nadir of 5 mm.
| Percentage of participants | Synovial Sarcoma: Cohort 2 |
|---|---|
| Cohort 2: Progression-Free Survival (PFS) Rate at 16 Weeks of Treatment With Tazemetostat | 15.2 (5.1 to 31.9) |
An AE was defined as any untoward medical occurrence in a participant or clinical investigation participant administered a medicinal product and which did not necessarily have a causal relationship with this treatment. An SAE was defined as any untoward medical occurrence that, at any dose: resulted in death, was life threatening, required hospitalization or prolongation of existing hospitalization, resulted in disability/incapacity, was a congenital anomaly/birth defect or was medically significant. TEAEs were defined as AEs if one of the following conditions met: emerged after the time of first dose administration, having been absent prior to the first dose; re-emerged, having been present but stopped prior to the time of first dose administration; worsened in severity after the time of first dose administration relative to the pretreatment state, when the AE was continuous.
| Participants | ES 1600 mg: Cohort 8 |
|---|---|
| TEAEs | 7 |
| TESAEs | 2 |
DOR was defined as time from the first documented evidence of CR or PR based on investigator review to the time of first documented PD or death due to any cause, whichever came first, as per RECIST v 1.1 criteria. CR was defined as disappearance of all target and non-target lesions. Any pathological lymph nodes must be \<10 mm in the short axis. PR was defined as at least 30% decrease in sum of diameters of target lesions, taking as a reference, baseline sum of diameters. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since the treatment started. In addition, the sum must have an absolute increase from nadir of 5 mm.
| Weeks | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 |
|---|---|---|---|---|---|---|---|---|
| All Cohorts: Duration of Response (DOR) | 29.0 (24.1 to 32.1) | — | 80.1 (24.1 to 87.6) | — | 88.0 (7.1 to 224.4) | 96.1 (10.3 to 112.3) | 151.6 (151.6 to 151.6) | 119.4 (119.4 to 119.4) |
PFS was defined as the interval of time between the date of the first dose of study treatment and the earliest date of PD or death due to any cause, whichever comes first, as per RECIST v 1.1 criteria. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since the treatment started. In addition, the sum must have an absolute increase from nadir of 5 mm.
| Weeks | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 |
|---|---|---|---|---|---|---|---|---|
| All Cohorts: Progression-Free Survival (PFS) | 7.9 (7.7 to 15.1) | 8.0 (7.6 to 8.1) | 15.7 (7.7 to 31.7) | 7.3 (6.3 to 15.1) | 23.7 (14.7 to 25.7) | 16.1 (8.4 to 16.6) | 24.0 (6.3 to 175.3) | 39.9 (4.1 to NA) |
PFS was defined as the interval of time between the date of the first dose of study treatment and the earliest date of PD or death due to any cause, whichever comes first, as per RECIST v 1.1 criteria. PFS rate at 24, 32 and 56 weeks were estimated. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since the treatment started. In addition, the sum must have an absolute increase from nadir of 5 mm. Estimates were calculated with Kaplan-Meier analysis and 95% CIs using the complementary log-log transformation.
| Percentage of participants | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 |
|---|---|---|---|---|---|---|---|---|
| Week 24 | 17.6 (6.5 to 33.1) | 15.9 (5.1 to 32.0) | 34.4 (18.2 to 51.2) | 15.4 (2.5 to 38.8) | 42.1 (29.3 to 54.4) | 33.8 (22.9 to 45.0) | 43.6 (18.2 to 66.7) | 53.6 (13.2 to 82.5) |
| Week 32 | 14.1 (4.5 to 28.9) | 10.6 (2.2 to 26.7) | 26.7 (12.3 to 43.5) | 15.4 (2.5 to 38.8) | 29.1 (17.9 to 41.2) | 29.3 (19.1 to 40.4) | 43.6 (18.2 to 66.7) | 53.6 (13.2 to 82.5) |
| Week 56 | 3.5 (0.3 to 15.2) | 0.0 (0.0 to 0.0) | 13.8 (3.8 to 29.9) | 0.0 (0.0 to 0.0) | 21.3 (11.6 to 33.0) | 22.6 (13.3 to 33.3) | 18.2 (1.5 to 50.3) | 26.8 (1.3 to 67.0) |
OS was defined as the interval of time between the date of the first dose of study treatment and the date of death due to any cause.
| Weeks | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 |
|---|---|---|---|---|---|---|---|---|
| All Cohorts: Overall Survival (OS) | 22.1 (14.4 to 54.6) | 43.4 (31.7 to 58.1) | 37.9 (23.3 to 104.0) | 24.6 (8.4 to 73.6) | 82.4 (47.4 to 117.0) | 111.4 (63.0 to NA) | 77.7 (32.9 to NA) | 49.6 (19.3 to NA) |
OS was defined as the interval of time between the date of the first dose of study treatment and the date of death due to any cause. OS rate at 24, 32 and 56 weeks were estimated. Estimates were calculated with Kaplan-Meier analysis and 95% CIs using the complementary log-log transformation.
| Percentage of participants | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 |
|---|---|---|---|---|---|---|---|---|
| Week 24 | 45.4 (27.6 to 61.6) | 81.4 (63.2 to 91.2) | 68.8 (49.7 to 81.8) | 50.0 (22.9 to 72.2) | 85.5 (73.9 to 92.2) | 83.6 (72.3 to 90.6) | 88.9 (62.4 to 97.1) | 83.3 (27.3 to 97.5) |
| Week 32 | 38.6 (21.8 to 55.2) | 68.9 (49.9 to 81.9) | 56.3 (37.6 to 71.3) | 42.9 (17.7 to 66.0) | 77.2 (64.6 to 85.8) | 75.8 (63.6 to 84.4) | 77.8 (51.1 to 91.0) | 66.7 (19.5 to 90.4) |
| Week 56 | 30.9 (15.5 to 47.7) | 37.6 (21.3 to 53.8) | 49.6 (31.4 to 65.4) | 35.7 (13.0 to 59.4) | 57.3 (43.9 to 68.6) | 66.5 (53.7 to 76.6) | 55.6 (30.5 to 74.8) | 44.4 (6.6 to 78.5) |
DCR was defined as the percentage of participants who achieved a confirmed response (CR or PR, as per RECIST v 1.1 criteria) or who have SD lasting at least 32 weeks from the start of treatment until disease progression or the start of subsequent anti-cancer therapy. CR was defined as disappearance of all target and non-target lesions. Any pathological lymph nodes must be \<10 mm in the short axis. PR was defined as at least 30% decrease in sum of diameters of target lesions, taking as a reference, baseline sum of diameters. SD was defined neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for progressive disease.
| Percentage of participants | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 |
|---|---|---|---|---|---|---|---|---|
| Week 12 | 21.9 (9.3 to 40.0) | 15.2 (5.1 to 31.9) | 40.6 (23.7 to 59.4) | 21.4 (4.7 to 50.8) | 45.2 (32.5 to 58.3) | 36.2 (25.0 to 48.7) | 50.0 (26.0 to 74.0) | 42.9 (9.9 to 81.6) |
| Week 24 | 12.5 (3.5 to 29.0) | 9.1 (1.9 to 24.3) | 21.9 (9.3 to 40.0) | 14.3 (1.8 to 42.8) | 29.0 (18.2 to 41.9) | 30.4 (19.9 to 42.7) | 33.3 (13.3 to 59.0) | 42.9 (9.9 to 81.6) |
| Week 32 | 9.4 (2.0 to 25.0) | 3.0 (0.1 to 15.8) | 18.8 (7.2 to 36.4) | 7.1 (0.2 to 33.9) | 25.8 (15.5 to 38.5) | 29.0 (18.7 to 41.2) | 27.8 (9.7 to 53.5) | 14.3 (0.4 to 57.9) |
| Week 48 | 9.4 (2.0 to 25.0) | 3.0 (0.1 to 15.8) | 12.5 (3.5 to 29.0) | 0.0 (0.0 to 23.2) | 24.2 (14.2 to 36.7) | 23.2 (13.9 to 34.9) | 11.1 (1.4 to 34.7) | 14.3 (0.4 to 57.9) |
ORR was defined as percentage of participants who achieved a confirmed CR or PR based on investigator assessment from start of treatment until PD or start of subsequent anti-cancer therapy or cancer-related surgery, whichever was earlier, as per RANO criteria for primary brain tumors or RECIST v 1.1 criteria for all other solid tumors. CR was defined as disappearance of all target and non-target lesions. Any pathological lymph nodes must be \<10 mm in the short axis. PR was defined as at least 30% decrease in sum of diameters of target lesions, taking as a reference, baseline sum of diameters. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as a reference, smallest sum of diameters recorded since the treatment started. In addition, the sum must have an absolute increase from nadir of 5 mm.
| Percentage of participants | Synovial Sarcoma: Cohort 2 | ES 1600 mg: Cohort 8 |
|---|---|---|
| Cohorts 2 and 8: Objective Response Rate (ORR) | 0 (0.0 to 10.6) | 14.3 (0.4 to 57.9) |
Collected over Treatment-emergent adverse events (TEAEs) were collected from first dose of study treatment (Day 1) up to 30 days after the last dose of study treatment, approximately 88 weeks (Cohort 1), 55 weeks (Cohort 2), 148 weeks (Cohorts 3 and 8), 48 weeks (Cohort 4), 304 weeks (Cohort 5), 270 weeks (Cohort 6) and 183 weeks (Cohort 7). All-cause mortality (deaths) were collected from first dose of study treatment (Day 1) up to 5.75 years.. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Rhabdoid Tumors: Cohort 1 | 9/32 (28.1%) | 18/32 (56.3%) | 27/32 (84.4%) |
| Synovial Sarcoma: Cohort 2 | 2/33 (6.1%) | 13/33 (39.4%) | 28/33 (84.8%) |
| Other INI1-Negative: Cohort 3 | 5/32 (15.6%) | 11/32 (34.4%) | 29/32 (90.6%) |
| RMC: Cohort 4 | 3/14 (21.4%) | 8/14 (57.1%) | 12/14 (85.7%) |
| ES: Cohort 5 | 8/62 (12.9%) | 25/62 (40.3%) | 58/62 (93.5%) |
| ES Paired Biopsy: Cohort 6 | 6/69 (8.7%) | 19/69 (27.5%) | 65/69 (94.2%) |
| Chordoma: Cohort 7 | 2/18 (11.1%) | 7/18 (38.9%) | 16/18 (88.9%) |
| ES 1600 mg: Cohort 8 | 0/7 (0%) | 2/7 (28.6%) | 6/7 (85.7%) |
| Event | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-Negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 |
|---|---|---|---|---|---|---|---|---|
| DyspnoeaRespiratory, thoracic and mediastinal disorders | 1/32 | 3/33 | 3/32 | 3/14 | 3/62 | 3/69 | 0/18 | 0/7 |
| DeathGeneral disorders | 5/32 | 0/33 | 4/32 | 3/14 | 4/62 | 2/69 | 2/18 | 0/7 |
| Pleural effusionRespiratory, thoracic and mediastinal disorders | 2/32 | 0/33 | 2/32 | 0/14 | 4/62 | 2/69 | 0/18 | 1/7 |
| Pulmonary embolismRespiratory, thoracic and mediastinal disorders | 0/32 | 1/33 | 0/32 | 2/14 | 1/62 | 1/69 | 0/18 | 0/7 |
| Respiratory failureRespiratory, thoracic and mediastinal disorders | 0/32 | 1/33 | 0/32 | 0/14 | 1/62 | 1/69 | 0/18 | 1/7 |
| Pneumonia staphylococcalInfections and infestations | 0/32 | 0/33 | 0/32 | 0/14 | 0/62 | 0/69 | 0/18 | 1/7 |
| Tumour painNeoplasms benign, malignant and unspecified (incl cysts and polyps) | 1/32 | 0/33 | 0/32 | 0/14 | 0/62 | 1/69 | 0/18 | 1/7 |
| Abdominal painGastrointestinal disorders | 3/32 | 0/33 | 1/32 | 0/14 | 1/62 | 0/69 | 0/18 | 0/7 |
| HaemoptysisRespiratory, thoracic and mediastinal disorders | 0/32 | 3/33 | 0/32 | 0/14 | 4/62 | 1/69 | 0/18 | 0/7 |
| PneumoniaInfections and infestations | 0/32 | 1/33 | 0/32 | 1/14 | 1/62 | 2/69 | 0/18 | 0/7 |
| Event | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-Negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 |
|---|---|---|---|---|---|---|---|---|
| Pleural effusionRespiratory, thoracic and mediastinal disorders | 3/32 | 3/33 | 2/32 | 3/14 | 4/62 | 4/69 | 0/18 | 4/7 |
| Decreased appetiteMetabolism and nutrition disorders | 3/32 | 4/33 | 3/32 | 8/14 | 15/62 | 9/69 | 3/18 | 2/7 |
| NauseaGastrointestinal disorders | 10/32 | 9/33 | 9/32 | 3/14 | 23/62 | 32/69 | 8/18 | 3/7 |
| VomitingGastrointestinal disorders | 13/32 | 1/33 | 9/32 | 5/14 | 16/62 | 9/69 | 5/18 | 3/7 |
| ConstipationGastrointestinal disorders | 7/32 | 4/33 | 5/32 | 4/14 | 13/62 | 10/69 | 3/18 | 3/7 |
| FatigueGeneral disorders | 7/32 | 10/33 | 11/32 | 3/14 | 24/62 | 21/69 | 4/18 | 3/7 |
| CoughRespiratory, thoracic and mediastinal disorders | 3/32 | 10/33 | 4/32 | 3/14 | 13/62 | 5/69 | 2/18 | 3/7 |
| DyspnoeaRespiratory, thoracic and mediastinal disorders | 7/32 | 8/33 | 4/32 | 4/14 | 6/62 | 7/69 | 0/18 | 3/7 |
| Weight decreasedInvestigations | 3/32 | 2/33 | 2/32 | 4/14 | 10/62 | 6/69 | 0/18 | 3/7 |
| Cancer painNeoplasms benign, malignant and unspecified (incl cysts and polyps) | 9/32 | 8/33 | 7/32 | 2/14 | 19/62 | 1/69 | 2/18 | 0/7 |
Intent-to-treat (ITT) population included all participants who received at least 1 dose of tazemetostat.
| Age, Continuous(Years) | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 | Total |
|---|---|---|---|---|---|---|---|---|---|
| Mean | 37.9 ± 16.31 | 38.8 ± 9.54 | 46.9 ± 16.94 | 30.7 ± 10.71 | 37.0 ± 15.08 | 41.3 ± 14.00 | 38.9 ± 17.49 | 40.9 ± 15.74 | 39.5 ± 14.89 |
| Sex: Female, Male(Participants) | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 | Total |
|---|---|---|---|---|---|---|---|---|---|
| Female | 19 | 12 | 17 | 4 | 23 | 26 | 8 | 4 | 113 |
| Male | 13 | 21 | 15 | 10 | 39 | 43 | 10 | 3 | 154 |
| Ethnicity (NIH/OMB)(Participants) | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 | Total |
|---|---|---|---|---|---|---|---|---|---|
| Hispanic or Latino | 0 | 5 | 4 | 1 | 7 | 4 | 0 | 0 | 21 |
| Not Hispanic or Latino | 31 | 28 | 27 | 13 | 53 | 55 | 17 | 7 | 231 |
| Unknown or Not Reported | 1 | 0 | 1 | 0 | 2 | 10 | 1 | 0 | 15 |
| Race (NIH/OMB)(Participants) | Rhabdoid Tumors: Cohort 1 | Synovial Sarcoma: Cohort 2 | Other INI1-negative: Cohort 3 | RMC: Cohort 4 | ES: Cohort 5 | ES Paired Biopsy: Cohort 6 | Chordoma: Cohort 7 | ES 1600 mg: Cohort 8 | Total |
|---|---|---|---|---|---|---|---|---|---|
| American Indian or Alaska Native | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
| Asian | 2 | 0 | 1 | 0 | 7 | 9 | 1 | 2 | 22 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 |
| Black or African American | 3 | 4 | 2 | 11 | 4 | 1 | 1 | 0 | 26 |
| White | 24 | 24 | 28 | 2 | 47 | 54 | 16 | 5 | 200 |
| More than one race | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Unknown or Not Reported | 2 | 5 | 1 | 1 | 4 | 4 | 0 | 0 | 17 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Yes — Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, annotated case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of study participants. Any requests should be submitted to www.vivli.org for assessment by an independent scientific review board.
Time frame: Where applicable, data from eligible studies are available 6 months after the studied medicine and indication have been approved in the US and EU or after the primary manuscript describing the results has been accepted for publication, whichever is later.
Access criteria: Further details on Ipsen's sharing criteria, eligible studies and process for sharing are available here (https://vivli.org/members/ourmembers/).
Data sharing details ↗ · vivli.org
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Studies of the drug tested here: Tazemetostat