GRN163L vs BAT in MF (Myelofibrosis)

What is the Purpose of this Study?

We are doing this study is to find out if an investigational drug called imetelstat (the study drug) can lead to better outcomes in people who have myelofibrosis (MF) when it is compared to other available therapies.

What is the Condition Being Studied?

Myelofibrosis (MF)

Who Can Participate in the Study?

Adults ages 18+ who are diagnosed with myelofibrosis (MF).

For more information about who can join this study, please contact the study team at or 919-684-9220.

Age Group

What is Involved?

This study is divided into 3 periods: the screening period, the study regimen period, and the follow-up period.

If you choose to join the study, during the screening period you will:

  • Have a physical exam
  • Have blood draws
  • Have a scan of your abdomen
  • Have a bone marrow sample taken

If you are found to be eligible during the screening period, you will continue on to the study regimen period. During this period, you will:

  • Visit our clinic for regular check-ups
  • Have blood draws
  • Answer questionnaires
  • Keep a diary of your symptoms on an electronic device
  • Be randomly assigned (like a coin flip) to 1 of 2 groups
    • If you are assigned to study regimen A, you will get the study drug
    • If you are assigned to study regimen B, you will get the best available therapy

Your study doctor will discuss the best available therapy options to treat you if you are assigned to regimen B. If your disease does not improve while you receive regimen B, you might be eligible to switch to regimen A and get the study drug.

The study regimen period will last for as long as you continue to receive a positive benefit from either regimen.

The follow-up period will begin when you or your study doctor decides to stop the study regimen. We will call you every 12 weeks during this period to see how you are doing and ask some questions.

Study Details

Full Title
A Randomized Open-Label, Phase 3 Study to Evaluate Imetelstat (GRN163L) Versus Best Available Therapy (BAT) in Patients with Intermediate-2 or High-risk Myelofibrosis (MF) Relapsed / Refractory (R/R) to Janus Kinase (JAK) Inhibitor
Principal Investigator
Associate Professor of Medicine
Protocol Number
IRB: PRO00109191
NCT: NCT04576156
Phase III
Enrollment Status