NEW myelofibrosis treatment approved on the NHS in England

We are pleased to report that higher risk myelofibrosis patients affected by enlarged spleen and/or anaemia to have access to momelotinib thanks to a decision made by the National Institute for Health and Care Excellence's (NICE) today.

Page last updated on: 15th February 2024

What is the news?

Today, momelotinib (Ojjaara©) has been approved as a new treatment option on the NHS for patients with myelofibrosis in England. It has been specifically approved for: 

  • Patients whose myelofibrosis is rated as intermediate-2 or high risk AND 
  • Have an enlarged spleen AND/OR moderate to severe anaemia.  

Treatment for myelofibrosis is not usually curative. Some patients are fit enough to have a stem cell transplant, but this not suitable for all. Most patients intermediate and high risk currently receive ruxolitinib instead, but it does not work for everyone. Momelotinib is now an extra option for patients who have never had treatment before, as well as those who have previously had ruxolitinib, allowing patients and doctors to choose the right treatment for them. 

Today’s news follows joint work between MPN Voice and Leukaemia Care to emphasise the importance of new treatment options for myelofibrosis patients. We submitted plenty of evidence from both surveys and patient stories to highlight why a new option is needed so badly. 

Our Policy and Evidence Manager, Charlotte Crowley, said:

“Today’s decision will provide access to only the second targeted treatment option for myelofibrosis in England. The symptoms of myelofibrosis are debilitating and can prevent people from going about their everyday lives. The evidence that reducing the symptoms of myeloproliferative neoplasms (MPNs) improves survival of these patients, as well as improving quality of life, is increasing.

We were really pleased to work with MPN Voice on this appraisal to ensure the experience of those with myelofibrosis are at the forefront of the decision-making process.”

Momelotinib was approved for these patients using the results of the SIMPLIFY-1 and SIMPLIFY-2 clinical trials, among other sources of information. The SIMPLIFY-1 trial specifically looked at people who had never had ruxolitinib before. The aim of the trial was to compare the number of people who achieved at least 35% reduction in spleen size. The results showed that momelotinib is non-inferior to ruxolitinib. This means that the drugs reduce the spleen size by at least 35% in a similar number of patients to each other. 

The SIMPLIFY-2 trial also looked at how many patients achieved a reduction in their spleen size, but this time in people who had already been treated with ruxolitinib. The patients needed different treatment either because the treatment had stopped working or due to side effects. Teh results of this trial were less clear, but the on balance the committee decided that momelotinib was likely to be a useful and cost effective treatment option.  

How does this affect access to treatments elsewhere in the UK? 

Decisions by the National Institute of Health and Care Excellence (NICE), such as today’s decision, only apply to England and Wales. Treatments usually become available with 90 days of approval. Northern Ireland usually chooses to adopt these recommendations too, but can be slower to make the treatment available.  

Scotland has a separate body that reviews treatments for use in NHS Scotland, the Scottish Medicines Consortium (SMC). The manufacturer must submit separately, and a separate process followed before treatments are made available there. We will continue to work with the SMC and companies to ensure everyone across the UK has equal access to effective treatments. If approved in Scotland, we will update you with another news articles.  

How does momelotinib work? 

Momelotinib is a JAK1/2 and ACVR-1 inhibitor. JAK1, JAK2 and ACVR-1 are proteins within cells that work within a pathway of proteins. In normal cells, the protein pathways carry signals from outside the cell to the various parts of the inside of cells. The signals allows our cells to respond to the environment, but cancer cells have edited versions or too much of the proteins. The changes to the protein pathways make the cancer cells do things they shouldn’t, such as replicate too much, causing the cancer symptoms.    

What does intermediate or high risk mean?  

Myelofibrosis patients, like those of many other blood cancers, often have different outcomes. As we increasingly understand more about the disease, researchers have pinpointed various factors that can help to predict a person’s likelihood of survival (otherwise known as prognosis). These factors have been put together into a scoring system, known as Dynamic International Prognostic Scoring System (DIPSS). DIPSS has 4 levels of risk; low, intermediate-1, intermidate-2 and high risk. Momelotinib is only available to those in the top two risk levels, as described above. 

The things that are considered when deciding on a person’s risk level include their age, their white cell count and their blood haemaglobin level, among other things. Speak to your doctor if you are not sure what risk level you are.  

How can I find out if momelotinib is an option for me/someone I know? 

Your haematologist or clinical nurse specialist should explain to you when treatment will be needed and why they are recommending any treatment, including why other treatments are not suitable or available. They should also be clear that treatment is a choice for you to make and the expected consequences of your choices for your health.  

Do you need support?

If you want to know more about what treatments are available for you, how treatment decisions are made or have any other question related to treatment, please contact us via our helpline 08088 010 444,  or send your question to WhatsApp on 07500 068 065 (services available Monday to Friday 9am – 5pm). Alternatively you can email our team at

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