I tried to post 3 months ago in April about recent transformation of Myelodysplastic syndrome ('MDS') to Myelofibrosis. I have grade 3 fibrosis of the bone marrow, enlarged spleen 20cm,JAK2 & SF3B1 mutations.
It took 6 weeks to come up with a treatment plan. I have been on 15mg of Ruxolitinib daily for 3 months. Today my ultrasound scan revealed my spleen hadn’t shrunk. Has anyone else experienced the drug not working ?
Hi @simwilkes and welcome to the forum.
You’ll find a really supportive group of people on the forum.
I was on Ruxolitinib for about 14 months after a Myelofibrosis diagnosis.
Spleen at time of diagnosis was 29cm. It did eventually reduce the spleen size but it took a while. Dipps plus score was 3 which equated to Intermediate 2. I know different scoring is used by different Haematology Teams
When treatment started I was on Azacitidine injections as well as the Ruxolitinib.
Few months after diagnosis progressed to Acute myeloid leukaemia ('AML') so had intensive chemotherapy Flag-ida.
When that didn’t deliver response hoped for had Venetoclax and Azacitidine as well as Ruxolitinib.
Eventually got blasts to a level where a Bone Marrow Transplant was offered. Had that in April 2025 thanks to an anonymous donor.
Hope that helps.
Hi @DuncanB , thank you for your reply, hope you are doing ok after your stem cell transplant 
. Do you know how long it took for your spleen to start shrinking whilst on the Ruxolitinib ? I am very aware that all blood cancer patients are very individual but would be good to know your case ?
I had to have my first blood transfusion 4 weeks ago as Hg dropped to 7.4, after holding up around 10ish for 12 years on EPO injections. Most other counts are just outside normal range.
I don’t know where I don’t ache some days, but keep plodding on .
Take care
Hello there @simwilkes, welcome back to the forum. I’m really glad you posted and may I just say how sorry I am about your diagnosis with Myelofibrosis (‘MF’) and its transformation from Myelodysplastic syndrome ('MDS').
I don’t imagine the enlarged spleen is much fun either—I remember mine being rather tender when I was diagnosed with Polycythaemia vera ('PV'). It took a month or so for the tenderness to fade after I started treatment with hydroxyurea, although it wasn’t classed as enlarged.
I see dear @DuncanB has shared his invaluable insights about taking ruxolitinib. This great information from Macmillan about MF treatments like ruxolitinib states; “You may be given a JAK inhibitor to help with your symptoms. If you have intermediate-risk or high-risk MF, these drugs can reduce an enlarged spleen.”
I wonder how long your doctors say it is meant to take for the ruxolitinib to shrink your spleen? I’d be tempted to ask them more about what to expect from treatment for MF. For reference, here is the Blood Cancer UK information about MF: Myelofibrosis (MF) | Blood Cancer UK
For what it’s worth, it took my hydroxyurea about 3 months to stop bringing up new side effects and seem to start bringing down my blood cell numbers and spleen tenderness. Maybe it’ll be similar with the ruxolitinib for you?
If you’d like to find others around the forum with experiences of ruxolitinib just use the search box at the top. I know of others who live with Polycythaemia vera ('PV') who have mentioned taking ruxolitinib, so if you wanted to reach out to anyone just add an @ before their username so they receive a notification.
You can also talk about medical queries with the lovely specialist nurses at Blood Cancer UK on 0808 2080 888.
Hope that helps get you started @simwilkes and that you receive further helpful responses. Do please keep us posted about how you get on.
Hi @simwilkes
Just checked wife’s extensive notes.
It took about 9 months for my spleen to return to something approaching normal.
After 3 months no noticeable change in spleen size.
As you say we are all different.
Hope that helps and take care