Randomized, Open Label, Multicenter Phase III Study of Efficacy and Safety in Polycythemia Vera Subjects Who Are Resistant to or Intolerant of Hydroxyurea: JAK Inhibitor INC424 Tablets Versus Best Available Care (The RESPONSE Trial)

Study Status

Open to Enrollment

Study Description

This clinical trial is for people diagnosed with polycythemia vera (PV), a blood disorder in which the bone marrow makes too many red blood cells.

The purpose of the study is to determine which treatment-- experimental drug called INC424 or the best available therapy--is better for treating PV. The study will also determine if INC424 is safe and has beneficial effects in people who have polycythemia vera.

Blood cells are made in the bone marrow. An enzyme called JAK2 sends signals telling the bone marrow to produce more blood cells when they are needed. But in most people who have polycythaemia vera, the JAK2 enzyme is faulty and this makes the bone marrow produce too many red blood cells. INC424 blocks the action of the JAK2 enzyme and may reduce the number of red blood cells.

Study participants will be randomly assigned to receive either INC424 or the best available therapy. If selected for best available therapy, participants and the study doctor will choose the treatment that best fits their condition.

Participants receiving INC424 will take 2 tablets daily for up to 80 weeks.

Disease Status and/or Stage

Polycythemia Vera (PV)


Incyte Corporation

Key Eligibility

  • Men and women age 18 and older
  • Diagnosed with polycythemia vera (PV) for at least 24 weeks
  • Detailed eligibility reviewed when you contact the study team

Principal Investigator

Richard Silver, MD


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Contact Us

For general inquiries, or if you need assistance finding a study, please contact:

Robert Hagerty
Subject Recruitment Manager
Tel: (646) 962-9340
[email protected]

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