Durability of Ruxolitinib for PV, Dr V in Targeted Oncology interview

[ainslie]

A few weeks ago there was some discussion on there was some discussion on her re the durability of Rux for PV. Below is a answer to that from Dr V in a interview with Targeted Oncolgy in Nov 2022

In polycythemia vera, ruxolitinib is valuable as a second-line choice when things don't go well with hydroxyurea. Patients then have much higher white blood cell counts, may have a big spleen, and of course, require phlebotomy. In that setting, it has been proven in 2 randomized studies that ruxolitinib provides a significant clinical benefit in normalizing blood cell count, improving quality of life, and decreasing spleen in those that have a big spleen. It appears after many years of follow-up that this is very durable, and possibly decreases the risk of early death from the complications of uncontrolled polycythemia vera. We use it often in the second-line setting, and it is a number 1 choice in PV.

[MCW22]

I was put on ruxolitinib after 2 years of hydroxy failed to bring my white count down. Initially it brought my whites down from 30 to 17 however after just over 2 years on it my whites are now mid to high 20s. All other counts are OK.

[ainslie in reply to MCW22]

what dose are you on and for how long, also what are your other counts in particular Hgb,Hct,platelets, are you venisecting

[MCW22 in reply to ainslie]

I take 2 x 5mg tablets in the morning and another 2 early evening. I expect to continue until told otherwise. My last results were

Wbc 29.2

Rbc 4.54

Hb 113

Hct 0.352

Mcv 78

Mch 25.0

Platelets 218

Neutrophils 22.19

Lymphocytes 1.46

Monocytes 1.75

Eosinophils 0.58

Basophils 2.34

Myelocytes 0.58

Blasts 0.29

Ferritin 45

Cholesterol 4.2

These are from 3 months ago as that is how often I've been having phone appointments. I had a blood test a couple of days ago but won't know the results until my next phone appointment in just over a week.

My consultants just seem to focus on hematocrit, platelets and Hb. They never commented on the white count, yet that is the one that worries me. I only ever had 4 venesections at diagnosis and before starting drugs. Hope this helps.

Carol

[ainslie in reply to MCW22]

how long have you been on Rux

[ainslie in reply to MCW22]

ah forgot, and what is your concern about whites

[MCW22]

To my knowledge high whites can contribute to blood clots. Also it makes me wonder if I am progressing from PV to MF

[ainslie in reply to MCW22]

I used to have high whites on venisection only, around 25 and when I looked in to it, it seemed a grey area as to how much of additional thrombotic risk high whites are and perhaps more relevant I think it was a talk by Dr Machinares at a recent conference said that although high whites maybe a increased risk, lowering them didnt reduce that risk for some reason. I was going to say when was your last BMB and when did you start Rux, I noticed on Rux some counts are slow in coming down but can come down further over time, looking at your Hct and HGB there isnt much room to increase the dose. What does your haem have to say about it.

[MCW22]

I've only had one BMB and it was after that they put me on ruxolitinib. I've been on the same dose since starting it and each appointment they say to continue on that dose. They seem happy with my numbers. I guess if they suggest a change in anything that would be the time to worry.