A Phase 1 Study of Ruxolitinib plus Abemaciclib to Treat Myelofibrosis


Full Title

A Phase I Study of Ruxolitinib Plus Abemaciclib for Patients with Primary or Post-polycythemia Vera/Essential Thrombocythemia Myelofibrosis


In this study, researchers want to find the highest dose of the drug abemaciclib that can be given safely with ruxolitinib in people with myelofibrosis that has developed on its own (primary myelofibrosis) or as a complication of the blood diseases polycythemia vera or essential thrombocythemia. In people with myelofibrosis, the bone marrow is not able to make enough blood cells. The spleen is bigger than normal, making the stomach feel very full. Patients may also have fever and night sweats.

Doctors think that giving ruxolitinib, a standard medication for myelofibrosis, in combination with abemaciclib (a breast cancer medication that is investigational in this study) may be a useful treatment. Both ruxolitinib and abemaciclib block specific proteins that play a role in cancer growth. By blocking these proteins, the drugs may cause myelofibrosis to stop growing.

Participants in this study will receive one of three doses of abemaciclib in combination with ruxolitinib. Both medications are taken orally (by mouth).

Who Can Join

To be eligible for this study, patients must meet several requirements, including:

  • Participants must have intermediate-risk or high-risk primary myelofibrosis or myelofibrosis associated with polycythemia vera or essential thrombocythemia.
  • Patients must have been taking ruxolitinib for at least 12 weeks and had an inadequate response, such as a persistently enlarged spleen or other symptoms.
  • Patients must be able to walk and do routine activities for more than half of their normal waking hours.
  • This study is for people age 18 and older.


For more information and to ask about eligibility for this study, please contact the office of Dr. Raajit Rampal at 646-608-3746.




Phase I (phase 1)

Disease Status

Newly Diagnosed & Relapsed/Refractory



ClinicalTrials.gov ID