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Bomedemstat vs Hydroxyurea for Essential Thrombocythemia (MK-3543-007)

Phase 3
Recruiting
Conditions
Essential Thrombocythemia
Interventions
Registration Number
NCT06456346
Lead Sponsor
Merck Sharp & Dohme LLC
Brief Summary

The purpose of this study is to evaluate the efficacy and safety of bomedemstat compared with hydroxyurea in cytoreductive therapy naïve essential thrombocythemia (ET) participants for whom cytoreductive therapy is indicated. Its primary objective is to compare bomedemstat to hydroxyurea with respect to durable clinicohematologic response (DCHR). The primary hypothesis is that bomedemstat is superior to hydroxyurea with respect to DCHR.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
300
Inclusion Criteria
  • Diagnosis of Essential Thrombocythemia (ET) based on World Health Organization Criteria for myeloproliferative neoplasms, and an indication for cytoreductive therapy regardless of age or risk status
  • Has a centrally assessed bone marrow fibrosis score of Grade 0 or Grade 1, as per a modified version of the European Consensus Criteria for Grading Myelofibrosis
  • Has received no prior cytoreductive treatment for their ET
  • Human Immunodeficiency Virus (HIV)-infected participants have well controlled HIV on antiretroviral therapy
  • Participants who are Hepatitis B surface antigen (HBsAg) positive are eligible if they have received Hepatitis B Virus (HBV) antiviral therapy for at least 4 weeks and have undetectable HBV viral load
  • Participants with history of Hepatitis C Virus (HCV) infection are eligible if HCV viral load is undetectable
Exclusion Criteria
  • History of any illness/impairment of gastrointestinal function that might interfere with drug absorption
  • History of a malignancy, unless potentially curative treatment has been completed with no evidence of malignancy for 2 years
  • HIV-infected participants with a history of Kaposi's sarcoma and/or Multicentric Castleman's Disease
  • Has an active infection requiring systemic therapy
  • Has had a major surgery <4 weeks prior to first dose of study intervention or has not recovered from side effects of major surgery >4 weeks prior to first dose

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
BomedemstatHydroxyurea placeboParticipants will receive active bomedemstat and hydroxyurea placebo daily for up to approximately 52 weeks. Dosage will be adjusted either up or down within specified time parameters for each participant to the dose that provides sufficient exposure to safely inhibit thrombopoiesis to decrease platelet counts to the target range. Participants who complete treatment at Week 52 will be eligible to continue treatment in the extended treatment phase. Unblinding will occur and placebo discontinued once all participants have completed at least 52 weeks of therapy or otherwise discontinued.
BomedemstatBomedemstatParticipants will receive active bomedemstat and hydroxyurea placebo daily for up to approximately 52 weeks. Dosage will be adjusted either up or down within specified time parameters for each participant to the dose that provides sufficient exposure to safely inhibit thrombopoiesis to decrease platelet counts to the target range. Participants who complete treatment at Week 52 will be eligible to continue treatment in the extended treatment phase. Unblinding will occur and placebo discontinued once all participants have completed at least 52 weeks of therapy or otherwise discontinued.
HydroxyureaHydroxyureaParticipants will receive active hydroxyurea and bomedemstat placebo daily for up to 52 weeks. Dosage will be adjusted either up or down within specified time parameters for each participant to the dose that provides sufficient exposure to safely inhibit thrombopoiesis to decrease platelet counts to the target range. Participants who complete treatment at Week 52 will be eligible to continue treatment in the extended treatment phase. Unblinding will occur and placebo discontinued once all participants have completed at least 52 weeks of therapy or otherwise discontinued.
HydroxyureaBomedemstat placeboParticipants will receive active hydroxyurea and bomedemstat placebo daily for up to 52 weeks. Dosage will be adjusted either up or down within specified time parameters for each participant to the dose that provides sufficient exposure to safely inhibit thrombopoiesis to decrease platelet counts to the target range. Participants who complete treatment at Week 52 will be eligible to continue treatment in the extended treatment phase. Unblinding will occur and placebo discontinued once all participants have completed at least 52 weeks of therapy or otherwise discontinued.
Primary Outcome Measures
NameTimeMethod
Durable Clinicohematologic Response (DCHR) RateUp to Week 52

DCHR rate is the percentage of participants with DCHR, defined as a confirmed reduction of platelet count to ≤400 × 10\^9/L, absence of white blood cell (WBC) count elevation to \>10 × 10\^9/L locally assessed to be due to ET, starting by Week 24 and maintained for at least 24 weeks, and the absence of any thrombotic or major hemorrhagic events or disease progression to myelofibrosis (MF), myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) by Week 52.

Secondary Outcome Measures
NameTimeMethod
Change From Baseline in Myelofibrosis Symptom Assessment Form version 4.0 (MFSAF v4.0) Individual Fatigue Symptom Item ScoreBaseline and pre-specified timepoints up to Week 52

The MFSAF v4.0 is a 7-item participant-reported myelofibrosis symptom assessment which asks respondents to report symptom severity at its worst for each of the 7 items on a 0 (Absent) to 10 (Worst Imaginable) numeric rating scale.

Change From Baseline in Patient-reported Outcomes Measurement Information System (PROMIS) Fatigue SF-7a Total Fatigue ScoreBaseline and pre-specified timepoints up to Week 52

The PROMIS F SF-7a is a 7-item participant-reported assessment that measures both the experience of fatigue and the interference of fatigue on daily activities over the past week. Response options are on a 5-point Likert scale, ranging from 1 = never to 5 = always.

Change From Baseline in MFSAF v4.0 Total Symptom ScoreBaseline and Week 52

The MFSAF v4.0 is a 7-item participant-reported myelofibrosis symptom assessment which asks respondents to report symptom severity at its worst for each of the 7 items on a 0 (Absent) to 10 (Worst Imaginable) numeric rating scale. The change from baseline in MFSAF total score for all symptoms will be presented.

Duration of Hematologic Remission (DOHR)Up to Week 52

For participants who demonstrate hematologic remission, DOHR is defined as the time from the first documented evidence of platelet and WBC counts reduction until platelet or WBC counts increase to above acceptable threshold.

Number of Participants Who Experience Thrombotic EventsUp to approximately 52 weeks

Thrombotic events include but are not limited to new or recurrent acute myocardial infarction, unstable angina, stroke, transient ischemic attack, deep venous thrombosis, pulmonary embolism, thrombotic digital ischemia, or other thrombotic events.

Number of Participants Who Experience Major Hemorrhagic EventsUp to approximately 52 weeks

Major hemorrhagic events include but are not limited to fatal bleeding, and/or symptomatic bleeding in a critical area or organ such as intracranial, intraspinal, intraocular, retroperitoneal, intra-articular or pericardial, or intramuscular with compartment syndrome, and/or bleeding causing a decrease in hemoglobin level of 2 g/dL or more, or leading to transfusion of 2 or more units of whole blood or red cells.

Disease Progression RateUp to Week 52

Disease progression rate is the percentage of participants with disease progression, defined as the transformation to post-essential thrombocythemia myelofibrosis, myelodysplastic syndrome, or AML as assessed by the adjudication committee.

Number of Participants Who Experience One or More Adverse Events (AEs)Up to approximately 52 weeks

An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.

Number of Participants Who Discontinue Study Intervention Due to an AEUp to approximately 52 weeks

An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.

Trial Locations

Locations (124)

Los Angeles Cancer Network ( Site 0025)

🇺🇸

Glendale, California, United States

Stanford Cancer Center ( Site 0024)

🇺🇸

Palo Alto, California, United States

Exempla Lutheran Medical Center ( Site 0014)

🇺🇸

Golden, Colorado, United States

Parkview Research Center at Parkview Regional Medical Center ( Site 0006)

🇺🇸

Fort Wayne, Indiana, United States

University of Michigan ( Site 0003)

🇺🇸

Ann Arbor, Michigan, United States

Duke University Health System (DUHS) ( Site 0012)

🇺🇸

Durham, North Carolina, United States

Oregon Health & Science University ( Site 0018)

🇺🇸

Portland, Oregon, United States

University of Texas Health Science Center at San Antonio ( Site 0021)

🇺🇸

San Antonio, Texas, United States

University of Virginia ( Site 0020)

🇺🇸

Charlottesville, Virginia, United States

VCU Health Adult Outpatient Pavillion ( Site 0008)

🇺🇸

Richmond, Virginia, United States

Scroll for more (114 remaining)
Los Angeles Cancer Network ( Site 0025)
🇺🇸Glendale, California, United States
Study Coordinator
Contact
213-977-1214

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