MPNAN NewsThis study is testing how well pacritinib works compared to other standard treatments in people with a type of blood cancer called myelofibrosis (MF) who also have very low platelet counts. MF can occur on its own (PMF) or after other MPN (PPV-MF or PET-MF).
Who Can Join
- People with moderate to high-risk MF based on a scoring system called DIPSS.
- People who have very low platelet counts (below 50,000 per microliter).
- People who have never used or used very little of a medicine called a JAK2 inhibitor.
How the Study Works
- Participants are randomly assigned to one of two groups:
- Pacritinib group:receives pacritinib 200 mg twice a day.
- Comparison group – Physician’s Choice therapy:
receives one standard medicine chosen before joining the study (options include corticosteroids, hydroxyurea, danazol, or low-dose ruxolitinib).
- For every 3 people who join, 2 will get pacritinib and 1 will get the comparison treatment.
- The treatment choice and previous JAK2 use are considered when assigning groups.
During the Study
- Treatment continues unless:
- The disease is getting worse.
- Side effects have become too difficult.
- The patient or doctor decides to stop.
- The patient starts another MF treatment.
- There is no changing allowed between study treatments.
- All participants will have regular checkups and tests for 24 weeks (about 6 months), even if they stop treatment early – unless they withdraw consent or have major medical changes.
After 24 Weeks
- Patients who are doing well can keep taking their assigned treatment.
- Everyone in the study will be followed for survival for about 2.5 years after joining.
Who Can Join the Study – Inclusion Criteria
You may be able to join if you have myelofibrosis (MF), which can be:
- Primary MF, MF after polycythemia vera (PT), or MF after essential thrombocythemia (ET).
- Platelet count less than 50,000 per microliter.
- Moderate to high risk MF based on a scoring system called DIPSS.
- Enlarged spleen that can be felt at least 5 cm below the ribs.
- MF symptoms that affect daily life (such as tiredness, abdominal pain, itching, bone pain, filling up quickly when you eat or night sweats).
- Age 18 or older.
Who Cannot Join the Study – Exclusion Criteria
You cannot join if any of these apply:
- Have had or plan to have a stem cell transplant.
- Have had your spleen removed or received radiation to the spleen in the past 6 months.
- Have already been treated with pacritinib.
- Have not stopped your MF treatment within 14 days before starting the study.
- Have used more than one JAK2 inhibitor or high doses or longtime use of ruxolitinib or use of other JAK2 inhibitors for more than 90 days.
- Have used experimental treatments recently (within 28 days).
Study Design
For more information on PACIFICA and a full list of clinical sites, please visit
PACIFICA Clinical Trial or ClinicalTrials.gov