A new phase 2 clinical trial testing the safety, efficacy, and tolerability of reparixin in myelofibrosis is now open. 

The open-label phase 2 study sponsored by Icahn School of Medicine at Mount Sinai aims to enroll 26 patients with myelofibrosis or post essential thrombocythemia or polycythemia vera related myelofibrosis in New York, New York. They are specifically targeting patients who are 18 years of age or older.

Read more about experimental therapies for myelofibrosis

Participants will receive 1200 mg of reparixin by mouth 3 times a day for 24 weeks. After this, they may continue receiving the treatment once a day for 4 weeks if they achieved stable disease or better, until loss of response, disease progression, unacceptable toxicity, patient or physician withdrawal, or termination of study by the sponsor.

The primary outcome measure will be the efficacy of the treatment as assessed by the International Working Group (IWG)/European Leukemia Net (ELN) criteria. Secondary outcome measures will be the response assessment of IWG/ELN, the bone marrow fibrosis grade, the number of adverse events, and any changes in spleen volume.

The study is not yet recruiting participants and is expected to start in May 2023. The estimated study completion date is March 2026. 

Reparixin is a CXC chemokine receptor type 1 (CXCR1) and 2 (CXCR2) inhibitor with potential antineoplastic activity. 

It binds to CXCR1 and prevents it from being activated by its ligand interleukin 8 (IL-8). CXCR1 is overexpressed on cancer stem cells playing a key role in their survival and ability to self-renew. By inhibiting the CXCR1/IL-8 interaction, reparixin may lead to cancer stem cell apoptosis and potentially inhibit tumor progression and metastasis. CXCR1 is also linked to tumor resistance to chemotherapy so reparixin may play a role in potentiating the cytotoxic effect of chemotherapy. 

By inhibiting the activation of CXCR2 reparixin may also reduce neutrophil recruitment and vascular permeability during inflammation or injury.


Reparixin in patients with myelofibrosis Myeloproliferative Neoplasms Research Consortium (MPN-RC 120). US National Library of Medicine. Updated April 28, 2023. Accessed April 30, 2023.

Reparixin. National Cancer Institute. Accessed April 30, 2023.