Tazemetostat in Combination With Doxorubicin as Frontline Therapy for Advanced Epithelioid Sarcoma
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ClinicalTrials.gov Identifier: NCT04204941 |
Recruitment Status :
Recruiting
First Posted : December 19, 2019
Last Update Posted : February 13, 2023
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Advanced Soft Tissue Sarcoma Advanced Epithelioid Sarcoma | Drug: Tazemetostat Drug: Placebo Drug: Doxorubicin HCl | Phase 3 |
Expanded Access : Epizyme, Inc. has indicated that access to an investigational treatment associated with this study is available outside the clinical trial.
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 164 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | None (Open Label) |
Masking Description: | Phase 1b is open label, phase 3 is not open label |
Primary Purpose: | Treatment |
Official Title: | A Phase 1b/3 Global, Randomized, Double-blind, Placebo-Controlled Trial of Tazemetostat in Combination With Doxorubicin as Frontline Therapy for Advanced Epithelioid Sarcoma |
Actual Study Start Date : | December 19, 2019 |
Estimated Primary Completion Date : | March 15, 2027 |
Estimated Study Completion Date : | May 1, 2029 |

Arm | Intervention/treatment |
---|---|
Experimental: Tazemetostat + Doxorubicin Arm
Tazemetostat (800 mg) administered orally twice daily in continuous 21-day cycles during cycles 1-6 and in continuous 28-day cycles during cycle 7 and beyond. Doxorubicin 75 mg/m2 IV on day 1 of cycles 1-6. |
Drug: Tazemetostat
Tazemetostat will be administered twice daily.
Other Name: EPZ-6438 Drug: Doxorubicin HCl 75mg/m2 intravenous injection day 1 of cycles 1 to 6 |
Experimental: Placebo + Doxorubicin Arm
Placebo administered orally twice daily in continuous 21-day cycles during cycles 1-6 and in continuous 28-day cycles during cycles 7 and beyond. Doxorubicin 75 mg/m2 IV on day 1 of cycles 1-6. |
Drug: Placebo
Placebo will be administered twice daily. Drug: Doxorubicin HCl 75mg/m2 intravenous injection day 1 of cycles 1 to 6 |
- Dose Limiting Toxicities (DLTs) as determined by Adverse Events following administration of Tazemostat in Combination with Doxorubicin [ Time Frame: 1 Cycle/21 days ]
Phase 1b: Evaluate the safety and tolerability of tazemetostat in combination with doxorubicin in subjects with advanced soft tissue sarcoma (STS) and select a dose for further evaluation in phase 3 (the RP3D)
Phase 3: Evaluate and compare the progression free survival (PFS) by independent review committee in subjects with advanced ES treated with tazmetostat + doxorubicin versus placebo + doxorubicin
- Progression free survival (PFS) [ Time Frame: through study completion, an average of one year. ]Phase 3 Evaluate and compare the PFS by independent review committee (IRC) in subjects with advanced ES treated with tazemetostat + doxorubicin versus placebo + doxorubicin through study completion, an average of one year.

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria
Subjects must meet ALL the following inclusion criteria to be eligible to enroll in this study:
- Have voluntarily agreed to provide written informed consent and demonstrated willingness and ability to comply with all aspects of the protocol. Study related activities will not start until written consent is obtained.
- Life expectancy ≥ 3 months before enrollment
- Phase 1b: 18-65 years old histologically confirmed Soft Tissue Sarcoma
- Phase 3: ≥18 years old with unresectable locally advanced or metastatic Epithelioid Sarcoma and tumor tissue available
- Have measurable disease
- ECOG performance status of 0, 1, or 2
- Have adequate hematologic (bone marrow [BM] and coagulation factors), renal and hepatic function as required per protocol
- Females must not be lactating or pregnant at Screening or Baseline
- Females must not be pregnant or breast feeding and agree to use highly effective contraception during the clinical trial and for 6 months following the final dose of study
- Male subjects of child-bearing potential must have had either a successful vasectomy or practice highly effective contraception
- Subjects diagnosed with human immunodeficiency virus (HIV) are eligible to participate in the study if their infection is well controlled on anti-retroviral therapy.
Exclusion Criteria
Subjects meeting ANY of the following exclusion criteria are NOT eligible to enroll in this study:
- Prior exposure to tazemetostat or other inhibitor(s) of enhancer of zeste homologue-2 (EZH2).
- Prior systemic anticancer therapy.
- Contraindications noted in the doxorubicin label
- Have any prior history of myeloid malignancies, including myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML).
- Have prior history of T-cell lymphoblastic lymphoma/T-cell acute lymphoblastic leukemia (T- LBL/T-ALL).
- Have participated in another interventional clinical study and received investigational drug within 30 days or 5 half-lives, whichever is longer, prior to the planned first dose of study treatment.
- Have known active central nervous system (CNS) or any leptomeningeal metastasis of primary extracranial tumor.
- Subjects taking medications that are known potent cytochrome P450 (CYP)3A4 inducers/inhibitors (including St. John's Wort)
- Are unwilling to exclude Seville oranges, grapefruit juice, AND grapefruit from the diet and all foods that contain those fruits from time of enrollment to through the duration of study participation.
- Major surgery within 4 weeks before the first dose of study treatment. Subjects must have recovered from surgery prior to enrollment to this study.
- Are unable to take oral medication OR have malabsorption syndrome or any other uncontrolled gastrointestinal condition (eg, nausea, diarrhea, vomiting) that might impair the bioavailability of study treatment.
- Have an active infection requiring systemic therapy.
- Are immunocompromised (ie, has a congenital immunodeficiency).
- Have known hypersensitivity to any component of tazemetostat or doxorubicin.
- Cardiovascular impairment as stated in the protocol
- Have a known active infection with hepatitis B virus (HBV, as measured by positive hepatitis B surface antigen), hepatitis C virus (HCV, as measured by positive hepatitis C antibody).
- Any other major illness that, in the Investigator's judgment, will substantially increase the risk associated with the subject's participation in this study OR interfere with their ability to receive study treatment or complete the study.
- Female subjects who are pregnant or breastfeeding.
- Subjects who have undergone a solid organ transplant.
- Subjects with malignancies other than STS (phase 1b) or ES (Phase 3 only).
- Subjects housed in an institution by order of the authorities or courts.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04204941
Contact: Medical Affairs | +1 (855) 500-1011 | clinicaltrials@epizyme.com |

Responsible Party: | Epizyme, Inc. |
ClinicalTrials.gov Identifier: | NCT04204941 |
Other Study ID Numbers: |
EZH-301 |
First Posted: | December 19, 2019 Key Record Dates |
Last Update Posted: | February 13, 2023 |
Last Verified: | February 2023 |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Sarcoma Neoplasms, Connective and Soft Tissue Neoplasms by Histologic Type Neoplasms Doxorubicin Liposomal doxorubicin |
Antibiotics, Antineoplastic Antineoplastic Agents Topoisomerase II Inhibitors Topoisomerase Inhibitors Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action |