Have you or a loved one been diagnosed with myelofibrosis and received treatment with an approved JAK inhibitor?

You could be eligible to participate in a clinical trial for patients with myelofibrosis.
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Myelofibrosis is a rare blood cancer that disrupts the normal production of blood cells in the human body. Myelofibrosis causes the formation of scar tissue or “fibrosis” in the bone marrow, impairing the bone marrow’s ability to produce healthy red blood cells and platelets. The loss of red blood cells and platelets can lead to anemia and thrombocytopenia, which may cause weakness, fatigue and life-threatening bleeding events.
As the bone marrow makes fewer and fewer healthy red blood cells, abnormal growth of blood-forming cancer cells may occur outside of the bone marrow in organs such as the spleen or liver causing them to become enlarged. An enlarged spleen is common in patients with myelofibrosis, and it may result in abdominal pain/discomfort, a feeling of early fullness and a decreased appetite.
Cancer cells also produce substances called “cytokines” that cause cancer-related inflammation. The abnormal release of these cytokines often results in disease related symptoms such as fatigue, night sweats, itching and fevers.
Patients with myelofibrosis typically need treatment. However, approved therapies only reduce the size of an enlarged spleen and relieve the symptoms associated with the cancer-related inflammation. Unfortunately, current treatments in myelofibrosis have been unsuccessful in restoring normal blood cell production or reversing the cancer driven bone marrow fibrosis.

Navtemadlin (KRT-232)

Navtemadlin (KRT-232) is an investigational therapy that targets a protein called MDM2, offering a potential new treatment for patients with myelofibrosis.
MDM2 is a protein that negatively regulates the activity of a tumor suppressor gene called p53, also known as the “Guardian of the Genome”.
Given the central role of p53 to control the natural lifecycle of cells within the human body, a delicate balance exists between MDM2 and p53. Unfortunately, in myelofibrosis, cancer cells abnormally increase MDM2 levels to shutdown p53 and its ability to fight cancer.
In patients with myelofibrosis, navtemadlin (KRT-232) treatment inhibits the high levels of MDM2 and restores the function of p53 and its ability to kill myelofibrosis cancer cells.


BOREAS is a global Phase 3 registration study for patients with myelofibrosis whose disease has progressed after treatment with a class of drugs called Janus kinase (JAK) inhibitors.
JAK inhibitors are used in the front line setting for patients with myelofibrosis and they are the only treatments options currently approved in the United States and Europe. There are no approved therapies in the second line setting for patients with myelofibrosis who are relapsed or refractory to a JAK inhibitor.
BOREAS will compare the efficacy and safety of navtemadlin (KRT-232) versus best available therapy in patients with myelofibrosis whose disease has progressed on or failed to respond to a JAK inhibitor.
Approximately 282 patients will participate in this study including 188 patients randomly assigned to navtemadlin (KRT-232) therapy and 94 patients assigned to best available therapy. For patients randomized to best available therapy, your treating physician will prescribe a therapy appropriate to you.
Before treatment starts, all patients will undergo complete clinical evaluations. Blood samples are collected to ensure the p53 protein is functional and not mutated. In addition, the spleen volume of all patients will be measured using MRI or CT scans and patients will fill out questionnaires to measure their constitutional symptoms. Blood work, imaging and the symptom questionnaire will occur prior to and throughout the study. For the first 24 weeks, patients remain on navtemadlin (KRT-232) or best available therapy unless they cannot tolerate treatment or their disease progresses.
After 24 weeks of treatment, efficacy will be analyzed comparing navtemadlin (KRT-232) to best available therapy using 2 assessments: (1) Spleen-volume reduction from study-start to 24 weeks by MRI or CT, and (2) Patients’ self-reported symptoms from study-start to 24 weeks.
As such, the two key measures of effectiveness for navtemadlin (KRT-232) compared to best available therapy are reduction in spleen-volume and improvement in symptoms after 24 weeks of treatment.

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Trial Locations

The BOREAS trial will be conducted in approximately 140 cancer centers across at least 20 countries. Please use the interactive map below to locate a cancer center near you where patients are being enrolled to this trial.

    Do You Qualify?

    • Are 18 years of age or older
    • Have received a diagnosis of myelofibrosis
    • Were previously treated with JAK inhibitors for myelofibrosis and were told that your disease has progressed

    Many other conditions must be met before you may participate in the trial. Please contact your nearest participating center. They will be able to give you more information about the requirements for the trial.

    If you would like to learn more about BOREAS Clinical Trial for Patients with Myelofibrosis, please fill out the form below.