Safety and Efficacy of Momelotinib in Subjects With Polycythemia Vera or Essential Thrombocythemia


  • Study type

  • Study phase

  • Study IDs

  • Describes the nature of a clinical study. Types include:

    • Observational study — observes people and measures outcomes without affecting results.
    • Interventional study (clinical trial) — studies new tests, treatments, drugs, surgical procedures or devices.
    • Medical records research — uses historical information collected from medical records of large groups of people to study how diseases progress and which treatments and surgeries work best.
  • During the early phases (phases 1 and 2), researchers assess safety, side effects, optimal dosages and risks/benefits. In the later phase (phase 3), researchers study whether the treatment works better than the current standard therapy. They also compare the safety of the new treatment with that of current treatments. Phase 3 trials include large numbers of people to make sure that the result is valid. There are also less common very early (phase 0) and later (phase 4) phases. Phase 0 trials are small trials that help researchers decide if a new agent should be tested in a phase 1 trial. Phase 4 trials look at long-term safety and effectiveness, after a new treatment has been approved and is on the market.

  • Site IRB
    • Scottsdale/Phoenix, Arizona: 14-000756
    NCT ID: NCT01998828
    Sponsor Protocol Number: GS-US-354-0101

About this study

This open-label study is to determine the safety and efficacy of momelotinib in participants with either polycythemia vera (PV) or essential thrombocythemia (ET) who have not yet received treatment with a Janus kinase (JAK) inhibitor.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. If you need assistance understanding the eligibility criteria, please contact the study team.

See eligibility criteria

Inclusion Criteria:

  • Diagnosis of either PV or ET as defined by the 2008 World Health Organization (WHO) Diagnostic Criteria
  • Requires treatment for PV or ET, in the opinion of the study investigator
  • Intolerant of, resistant to, or refuses current or available treatment for PV or ET
  • Direct bilirubin ≤ 2.0 x upper limit of the normal range (ULN)
  • Aspartate transaminase (AST) and alanine transaminase (ALT) ≤ 3 x ULN
  • Calculated creatinine clearance (CrCl) of ≥ 45 mL/min
  • Life expectancy > 24 weeks
  • Male subjects and female subjects of childbearing potential who engage in heterosexual intercourse must agree to use protocol specified method(s) of contraception
  • Females who are nursing must agree to discontinue nursing before the first dose of study drug
  • Able to comprehend and willing to sign informed consent form

Exclusion Criteria:

  • Prior splenectomy
  • Uncontrolled intercurrent illness, per protocol
  • Known positive status for human immunodeficiency virus (HIV)
  • Chronic active or acute viral hepatitis A, B, or C infection, or hepatitis B or C carrier
  • Myeloproliferative neoplasm-directed therapy, other than aspirin, hydroxyurea, anagrelide, and/or phlebotomy, within 21 days prior to the first dose of study drug
  • Anagrelide within 7 days prior to the first dose of study drug
  • Presence of peripheral neuropathy ≥ Grade 2
  • Unwilling or unable to take oral medication
  • Prior use of a JAK1 or JAK2 inhibitor
  • Use of strong CYP3A4 inhibitors or strong inducers CYP3A4 within 1 week prior to the first dose of study drug
  • QTc interval > 450 msec, unless attributed to bundle branch block

Participating Mayo Clinic locations

Study statuses change often. Please contact us for help.

Mayo Clinic Location Status Contact

Scottsdale/Phoenix, Ariz.

Mayo Clinic principal investigator

Ruben Mesa, M.D.

Closed for enrollment

Contact information:

Research Information Center



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