Myelofibrosis (MF) is a type of blood cancer in which the cells in the bone marrow responsible for producing blood are replaced by scar tissue. In 2024, just over 100 people were diagnosed with MF. These patients do not make enough red blood cells, white blood cells and/or platelets. That deficiency can cause fatigue, bruising, a higher risk of infections, and an enlarged spleen, among other symptoms. This has a major effect on the quality of life of people with MF.

Treatment of MF

Treatment of MF is currently limited to so-called JAK inhibitors. These work well initially but have side effects, including a reduction in red and white blood cells and platelets. In addition, the effectiveness of JAK inhibitors decreases over time. Other available drugs only provide symptom relief but do not affect the underlying disease in the bone marrow. Therefore, an effective treatment that targets the root cause of the disease with long-lasting benefits is urgently needed.

Normal numbers of blood cells

Rebekka Schneider, a researcher affiliated with Oncode Institute and Erasmus MC, discovered a drug that may also be effective for MF. This drug, Tasquinimod, inhibits blood vessel formation and stimulates the immune system. It was originally developed to treat prostate cancer but was found to influence the disease process of MF as well. Treatment with Tasquinimod in mice with MF resulted in normal numbers of white and red blood cells and platelets, and a reduction of scarring in the bone marrow. In addition, the size of the spleen normalised.

'Repurposing' of drugs

Tasquinimod has been extensively tested in previous clinical trials, and its safety profile is well characterised in humans. This investigational drug has already completed an important, but uncertain and time-consuming, process of drug development. Laboratory results suggest that this drug could be an effective treatment for MF. This process is called drug repurposing or “repurposing.” This may allow drugs such as Tasquinimod to be developed more quickly and more cost-efficiently for new patient groups.

Clinical study

Oncode Institute is making an effort to bring new cancer treatments to patients as quickly as possible. Drug repurposing is one way to do this. In that context, Schneider received a Clinical Proof-of-Concept (CPoC) grant and support from experts, enabling her to set up a collaboration for a clinical study to prove that Tasquinimod is effective in treating MF patients.

The CPoC programme is part of Oncode Institute's efforts to accelerate the translation of promising cancer treatments from the lab to the clinic.

Study details

Specifically, the goal of this study is to investigate the efficacy of Tasquinimod in MF patients who were being treated with JAK inhibitors but had to discontinue them due to side effects, or who were not eligible for JAK inhibitor treatment. The study is a collaboration between Oncode Institute, Erasmus MC, Active Biotech and HOVON (Dutch-Belgian Cooperative Trial Group for Haematology). Recently, the first patient was included, marking the start of the study.

Faster way to treat patients

Drug repurposing can help urgently needed treatments reach patients more quickly. There are many drugs already on the market that may also have potential efficacy for other disease states. Exploring that efficacy for other indications offers prospects for a cost-effective and time-efficient way to deal with costly drugs.