Phase II Study of SAR302503 in Subjects Previously Treated with Ruxolitinib and with a diagnosis of Intermediate-2 or High-Risk PM, Post-PV Myelofibrosis, or Post-ET Myelofibrosis

Study Status

Open to Enrollment

Study Description

This is a clinical trial for men and women with intermediate-2 or high-risk Primary Myelofibrosis (PMF), Post-Polycythemia Vera Myelofibrosis (Post-PV MF) or Post-Essential Thrombocythemia Myelofibrosis ((Post-ET MF).

The purpose of this research study is to determine if a once daily dose of SAR302503 is effective in treating men and women with myelofibrosis who were previously treated with ruxolitinib.

SAR302503 is an experimental compound being developed as an orally available treatment for myelofibrosis. SAR302503 acts on a substance in blood cells; the substance is related to the genetic marker called JAK2, which is found in many patients with myelofibrosis.

All study participants will receive SAR302503; there is no placebo.  There is a 6-month, 6-cycle treatment period.  Participants will take the study drug by mouth once daily in consecutive 28-day cycles.

Participants who continue to benefit clinically will be allowed to remain on SAR302503 beyond the 6-month treatment period as long as they tolerate the medication. 


Sanofi Aventis

Key Eligibility

  • Men and women age 18 and older
  • Diagnosis of High-Risk Primary Myelofibrosis (PMF), Post-Polycythemia Vera Myelofibrosis (Post-PV MF), or Post-Essential Thrombocythemia Myelofibrosis (Post-ET MF)
  • Myelofibrosis is classified as high-risk or intermediate-risk level 2
  • Have previously received ruxolitinib treatment
  • 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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