Study of the EZH2 Inhibitor Tazemetostat in Malignant Mesothelioma

• ClinicalTrials.gov Identifier: NCT02860286
• Recruitment Status: Completed
• First Posted: August 9, 2016
• Last Update Posted: September 25, 2019
• Sponsor: Epizyme, Inc.
• Information provided by (Responsible Party): Epizyme, Inc.

Study Description

Brief Summary:

This is a Phase 2, multicenter, open-label, 2-part, single-arm, 2-stage study of tazemetostat 800 mg two times a day (BID) administered orally. Screening of subjects to determine eligibility for the study will be performed within 21 days of the first planned dose of tazemetostat.

In Part 1, 12 subjects with relapsed or refractory malignant mesothelioma regardless of BAP1 status will be treated and undergo pharmacokinetics (PK) blood sample collection after a single tazemetostat 800 mg.

Part 2 will include subjects with BAP1-deficient relapsed or refractory malignant mesothelioma.

Treatment with tazemetostat will continue until disease progression, unacceptable toxicity or withdrawal of consent, or termination of the study. Response assessment will be evaluated after 6 weeks of treatment and then every 12 weeks thereafter while on study.

Condition or disease	Intervention/treatment	Phase
Mesothelioma; BAP1 Loss of Function	Drug: Tazemetostat	Phase 2

Study Design

• Study Type: Interventional (Clinical Trial)
• Actual Enrollment: 74 participants
• Allocation: N/A
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Primary Purpose: Treatment
• Official Title: A Multicenter Study of the EZH2 Inhibitor Tazemetostat in Adult Subjects With Relapsed or Refractory Malignant Mesothelioma With BAP1 Loss of Function
• Study Start Date: July 2016
• Actual Primary Completion Date: June 2018
• Actual Study Completion Date: May 2019

Arms and Interventions

Arm	Intervention/treatment
Experimental: Open-Label Tazemetostat; Oral Tazemetostat 800mg BID	Drug: Tazemetostat; Tazemetostat (EPZ-6438) is a selective small molecule inhibitor of the histone-lysine methyltransferase EZH2 gene.; Other Names: EPZ-6438; E7438

Outcome Measures

Primary Outcome Measures :

1. Part 1: Pharmacokinetics profile of tazemetostat and its metabolite (plasma): Cmax [ Time Frame: Days 1 and 15 ]
2. Part 1: Pharmacokinetics profile of tazemetostat and its metabolite (plasma): Tmax [ Time Frame: Days 1 and 15 ]
3. Part 1: Pharmacokinetics profile of tazemetostat and its metabolite (plasma): AUC(0-t) [ Time Frame: Days 1 and 15 ]
4. Part 1: Pharmacokinetics profile of tazemetostat and its metabolite (plasma): AUC(0-∞) [ Time Frame: Days 1 and 15 ]
5. Part 1: Pharmacokinetics profile of tazemetostat and its metabolite (plasma): t1/2 [ Time Frame: Days 1 and 15 ]
6. Part 1: Incidence of treatment-emergent adverse events as a measure of safety and tolerability [ Time Frame: Adverse events assessed from first dose through 30 days post last dose ]
7. Part 2: To assess disease control rate (DCR) defined as number of subjects with complete response (CR), partial response (PR) and stable disease (SD) [ Time Frame: 12 weeks ]

Secondary Outcome Measures :

1. Part 1 and 2: Incidence of treatment-emergent adverse events as a measure of safety and tolerability [ Time Frame: Adverse events assessed from first dose through 30 days post last dose ]
2. Part 1 and 2: Overall response rate (ORR; complete response + partial response [CR + PR]) [ Time Frame: Assessed every 6 weeks for duration of study participation which is estimated to be 12 months ]
3. Part 1 and 2: Progression-free survival (PFS) [ Time Frame: 12 weeks and 24 weeks as the time from the date of the first dose of study treatment to the date of death due to any cause ]
4. Part 1 and 2: Overall survival (OS) [ Time Frame: 12 weeks and 24 weeks as the time from the date of the first dose of study treatment to the date of death due to any cause assessed for up to 24 months ]
5. Part 1 and 2: To evaluate the duration of response (DOR) in subjects with confirmed CR or PR [ Time Frame: Every 6 weeks up to disease progression or start of new anti-cancer therapy assessed for up to 12 months ]
6. Part 1: Disease Control Rate (DCR) [ Time Frame: 12 weeks ]
7. Part 2: Population PK parameters: Cmax [ Time Frame: Days 1 and 15 of Cycle 1, and Days 1 of Cycles 2 through 4, where each cycle is 21 days ]
8. Part 2: Population PK parameters: Tmax [ Time Frame: Days 1 and 15 of Cycle 1, and Days 1 of Cycles 2 through 4, where each cycle is 21 days ]
9. Part 2: Population PK parameters: AUC(0-t) [ Time Frame: Days 1 and 15 of Cycle 1, and Days 1 of Cycles 2 through 4, where each cycle is 21 days ]
10. Part 2: Population PK parameters: AUC(0-∞) [ Time Frame: Days 1 and 15 of Cycle 1, and Days 1 of Cycles 2 through 4, where each cycle is 21 days ]
11. Part 2: Population PK parameters: t1/2 [ Time Frame: Days 1 and 15 of Cycle 1, and Days 1 of Cycles 2 through 4, where each cycle is 21 days ]
12. Part 2: Changes in H3K27me3 levels in tumor tissue as assessed by IHC [ Time Frame: 6 or 12 weeks ]

Eligibility Criteria

• Ages Eligible for Study: 18 Years and older (Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Criteria

Inclusion Criteria:

1. Age (at the time of consent) ≥18 years of age
2. Has an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
3. Has a life expectancy of >3 months
4. Has mesothelioma (pleural, peritoneal, pericardial, tunica vaginalis) of any histology that is relapsed or refractory after treatment with at least one pemetrexed-containing regimen
5. Has a documented local diagnostic pathology of original biopsy confirmed by a Clinical Laboratory Improvement Amendments (CLIA)/College of American Pathologists (CAP) or equivalent laboratory certification
6. Part 2: Molecular evidence of BAP1 loss of function mutation present on local pathology, e.g., lack of nuclear BAP1 staining by immunohistochemistry (IHC) or evidence of loss of function by gene sequencing
7. Has sufficient archival tumor tissue (a minimum of 10 slides or tumor block) available for central retrospective testing of BAP1 status
8. Has all prior treatment (i.e., chemotherapy, immunotherapy, radiotherapy) related clinically significant toxicities resolve to ≤ Grade 1 per CTCAE, version 4.03 or are clinically stable and not clinically significant, at time of enrollment

9. Prior therapy(ies), if applicable, must be completed according to the criteria below prior to first dose of tazemetostat:

   • Cytotoxic chemotherapy; at least 21 days since last dose
   • Non-cytotoxic chemotherapy (e.g., small molecule inhibitor); at least 14 days since last dose
   • Monoclonal antibody; at least three half-lives since the last dose
   • Non-antibody immunotherapy (e.g., tumor vaccine); at least 42 days since last dose
   • Radiotherapy, at least 14 days from last local site radiotherapy
   • Hematopoietic growth factor; at least 14 days from last dose
   • Investigational drug; 30 days or five half-lives, whichever is longer, from last dose
10. Has measurable disease based on either modified RECIST [Nowak 2005] for thoracic disease or RECIST 1.1 elsewhere

11. Has adequate hematologic (bone marrow and coagulation factors), renal, and hepatic function as defined by criteria below:

    • Hemoglobin ≥9 mg/dL
    • Platelets ≥100,000/mm3 (≥100 × 109/L) without platelet transfusion for 7 days
    • ANC ≥1000/mm3 (≥1.0 × 109/L) without growth factor support for 14 days
    • Coagulation: Prothrombin time (PT) <1.5 × ULN and partial thromboplastin time (PTT) <1.5 × ULN
    • Creatinine < 2.0 × ULN
    • Hepatic function: Conjugated bilirubin <1.5 × ULN and ALT and AST <3 × ULN
12. Has a QT interval corrected by Fridericia's formula (QTcF) ≤480 msec
13. Willing to provide tissue for translational research
14. Female subjects of childbearing potential must have a negative urine or serum pregnancy within 72 hours prior to receiving the first dose of study drug; if the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required and subject also should agree to use an adequate method of contraception starting with screening through 30 days after the last dose of study therapy (if sexually active).
15. Male subjects should agree to use condoms starting with the first dose of study therapy through 30 days after the last dose of study therapy if sexually active with a female of childbearing potential

Exclusion Criteria:

1. Has had prior exposure to tazemetostat or other inhibitor(s) of enhancer of zeste homologue-2 (EZH2)
2. Has a history of known central nervous system metastasis
3. Has had a prior malignancy other than the malignancies under study Exception: A subject who has been disease-free for 5 years, or a subject with a history of a completely resected non-melanoma skin cancer or successfully treated in situ carcinoma is eligible.
4. Has had major surgery within 3 weeks prior to enrollment (a percutaneous biopsy, pleural catheter insertion, placement of central venous catheter or other minor procedure are permitted)
5. Is unwilling to exclude grapefruit juice, Seville oranges and grapefruit from the diet and all foods that contain those fruits from time of enrollment throughout their time on study
6. Has cardiovascular impairment, history of congestive heart failure greater than NYHA Class II, uncontrolled arterial hypertension, unstable angina, myocardial infarction, or stroke within 6 months prior to the planned first dose of tazemetostat; or ventricular cardiac arrhythmia requiring medical treatment
7. Is currently taking any prohibited medication(s)
8. Has an active infection requiring systemic treatment
9. Has a congenital or acquired immunodeficiency, including subjects with known history of infection with human immunodeficiency virus (HIV) NOTE: HIV-positive subjects who are taking antiretroviral therapy are ineligible due to potential PK interactions with tazemetostat.
10. Has known history of chronic infection with hepatitis B virus (hepatitis B surface antigen positive) or hepatitis C virus (detectable anti-hepatitis C circulating viral RNA)

11. Has had a deep venous thrombosis (DVT) or pulmonary embolism within the 3 months prior to study enrollment.

    NOTE: Subjects with a history of a DVT or pulmonary embolism >3 months prior to study enrollment who are on anticoagulation therapy with low molecular weight heparin are eligible for this study.

12. Is pregnant or breastfeeding.

Contacts and Locations

Locations

United States, California

University of California, Los Angeles

Los Angeles, California, United States, 90025

City of Hope National Medical Center

Los Angeles, California, United States, 90301

University of California San Francisco

San Francisco, California, United States, 94143

United States, Massachusetts

Massachusetts General Hospital

Boston, Massachusetts, United States, 02114

Dana-Farber Cancer Institute

Boston, Massachusetts, United States, 02215

United States, Minnesota

Mayo Clinic - Rochester

Rochester, Minnesota, United States, 55905

United States, New York

Memorial Sloan Kettering Cancer Center

New York, New York, United States, 10065

France

Institut Bergonie

Bordeaux Cedex, France, 33076

CHRU de Lille

Lille, France, 59037

Institut Gustave Roussy

Villejuif cedex, France, 94805

United Kingdom

University Hospital of South Manchester

Greater Manchester, United Kingdom, M23 9LT

University of Leicester & Leicester University Hospitals

Leicester, United Kingdom, LE1 9HN

St. Bartholomew's Hospital

London, United Kingdom, EC1M 6BQ

University College Hospital

London, United Kingdom, NW1 2PG

Royal Marsden Hospital - Chelsea

London, United Kingdom, SW3 6JJ

Royal Marsden Hospital - Surrey

Surrey, United Kingdom, SM2 5PT

Sponsors and Collaborators

Epizyme, Inc.

More Information

• Responsible Party: Epizyme, Inc.
• ClinicalTrials.gov Identifier: NCT02860286
• Other Study ID Numbers: EZH-203
• First Posted: August 9, 2016
• Last Update Posted: September 25, 2019
• Last Verified: September 2019

Individual Participant Data (IPD) Sharing Statement:

• Plan to Share IPD: Yes

Additional relevant MeSH terms:

Mesothelioma; Adenoma; Neoplasms, Glandular and Epithelial; Neoplasms by Histologic Type; Neoplasms; Neoplasms, Mesothelial