MK-3543 vs Hydroxyurea in Cytoreductive Therapy Naïve Essential Thrombocythemia

Purpose of this Study

We are doing this study to find the most effective, safe dose of an experimental drug called bomedemstat or hydroxyurea in people with essential thrombocythemia (ET). We also want to know which of these options works best for most people.

Who Can Participate?

Eligibility

Adults ages 18+ who:<ul>
<li>Are diagnosed with ET and appropriate for cytoreductive therapy</li>
<li>Have a bone marrow fibrosis score of Grade 0 or Grade 1</li>
<li>Have never received any form of cytoreductive treatment</li>
<li>Are able to take hydroxyurea</li></ul>
For more information about who can join this study, please contact the study team at 919-668-2556.

What is Involved?

If you decide to participate in this study, you will have a screening visit to see if you are eligible for this study.

If you are eligible to join this study, you will get a random assignment (like a coin flip) to 1 of 2 groups:
<ul>
<li>Group 1: you will take bomedemstat and placebo (inactive substance or "sugar pill") for hydroxyurea</li>
<li>Group 2: will take hydroxyurea and placebo for bomedemstat</li></ul>
Bomedemstat and hydroxyurea are capsules. They are both taken daily by mouth. This is a "blind" study, so you will not know what group assignment you get.

After you get your group assignment, you will proceed to the study drug period. This period has 2 phases: Initial Study Drug Phase and Extended Study Drug Phase.

The Initial Study Drug Phase lasts for about 1 year. You will visit our clinic every other week for the first 12 weeks, and then about once per month.

When you finish the Initial Study Drug Phase, you will continue to use the study drug for up to 2 more years. This is called the Extended Study Drug Phase. During this phase, you will continue to get the same drug you got during the Initial Study Drug Phase. You will visit our clinic about once per month during this phase.

During the study you will undergo tests and procedures including:
<ul>
<li>Full physical examination</li>
<li>12-lead ECG</li>
<li>Blood for safety assessments and urine or serum for pregnancy</li>
<li>Bone marrow aspirate and biopsy</li>
<li>Blood for pharmacokinetics and biomarker assessments</li></ul>

Study Details

Full Title

A Phase 3, Randomized, Double-blind, Active-Comparator-Controlled
Clinical Study to Evaluate the Efficacy and Safety of Bomedemstat (MK-3543) versus
Hydroxyurea in Cytoreductive Therapy Naïve Essential Thrombocythemia Participants

Principal Investigator

Lindsay
Rein

Protocol Number

PRO00115732

NCT ID

NCT06456346

Phase

III

Enrollment Status

Pending Open to Enrollment