This study is looking at how well a drug called Reparixin works for people with a type of blood cancer called myelofibrosis. In this study, 26 patients will take Reparixin pills three times a day for a 4-week cycle, for a total of 6 cycles (24 weeks). After that, if the cancer hasn't gotten worse, they can keep taking the medicine once a day. This study is for people who have tried other treatments that didn't work or can't take a medicine called JAK inhibitor anymore.

• The study will last for 24 weeks, with possible extension if the disease is stable.
• Participants need to visit the doctor regularly for check-ups.
• Patients will need to have a bone marrow biopsy, a test that looks at the inside of your bones.

To join the study, you must be at least 18 years old and willing to sign a consent form. You can't join if you have certain health problems, like recent heart issues or infections. It's important to talk to your doctor to see if this study is right for you.