PCV besremi and low platelets

[gjh8733]

dear all

Sharing my latest health adventure and appreciate any insights

I have PCV since 2020 and been on Besremi for just over a year. My biweekly dose has been 500 ug since January so the max. My last phlebotomy was in March (before was every 2-3 months) and since that my hematocrit has been in 40-44 range so controlled

Up to June my platelet count was pretty stable around 300 however since then it has consistently dropped at each monthly check. On Oct 20 it was 174 and on Nov 3 it was 86. Given the trend it’s hard to say it was spurious reading

My oncologist at MGH said to pause my Besremi for a few weeks and see if there is any recovery.

Additional factor worth mentioning is that from around June I have had daily bouts of mild headache, flushed face and sensitive skin which I feel is besremi associated. Any NSAID has generally worked well at the lowest dose e.g. 200 mgs ibuprofen So I am on a chronic but low dose NSAID course

Any thoughts much appreciated am v happy w the clinical benefits of besremi so don’t like stopping it but platelet drop is concerning

Gerry

[hunter5582]

The drop in PLT is almost certainly due to the high dose of Besremi. I am only taking 150mcg and my historic cycle of thrombocytosis between 500s and 700s has reduced to well under 400 on that dose.

Many of us do not need the max dose of Besremi to achieve the treatment benefit. Suggest discussing a reduced dose with your MPN care team moving forward. I would also note that on 150mcg I have seen a reduction in JAK2 allele burden from 38% to 9% in 18 months. I retest in December. I am hoping for a deeper molecular response that matches my significantly improved quality of life on 150mcg Besremi.

[gjh8733 in reply to hunter5582]

Thanks Hunter. I will update after a few weeks go by re platelets. A reduced dose would also hopefully remove the AEs I feel are associated with Besremi

[hunter5582 in reply to gjh8733]

You are correct that AEs are dose dependant. That is one of the reasons that many of us prefer the low and slow approach to dosing Besremi. Hopefully you will find a lower dose more suitable.

[artandcats in reply to hunter5582]

Please excuse my ignorance, I’m in the U.S. and I don’t know what AE’s are . Please tell my what the letters stand for? E might be effects? Thanks.

[hunter5582 in reply to artandcats]

Adverse Effects

[ainslie]

I am curious why your doc didn’t just lower dose instead of pausing, maybe he/she plans a dose reduction after the pause. I take it you have PV, as opposed to PCV.?

[gjh8733 in reply to ainslie]

I have polycythemia Vera. I am guessing the low count made my oncologist feel a break is needed to allow the quickest recovery ?

One question I have is whether a reduction of frequency (ie treatment every 3-4 weeks) would to be as effective as reduction in dose. There was a publication I thought I saw where a maintenance dose every month seemed to be working. and one did not have to waste the besremi with a reduced dose.

[ainslie in reply to gjh8733]

Unfortunately I dont know the answer to your question, in fact there may not a a definitive answer, I know with Peg some experts are fine with spacing out the injections but others prefer smaller dose more regular. I dont know so much about Bes though.

[GardNerd]

I’m having a similar experience. My doctor’s approach was to take me to the max dose of Besremi that I could tolerate, so I steadily moved to 500 Mcl. I tolerated it well from a side effect standpoint, but my platelets went steadily downward. He’s now gradually taking the dose downward to find the “sweet spot” of controlling things. I’m now down to 400 and will get a CBC next week to see if the platelets are stabilizing and then, hopefully, increasing. I’m also surprised that your doc paused the Besremi instead of reducing the dose. Like Ainslie said, maybe it’s a pause and then a reduction. Hang in there! I think it takes a while to find that dose that will control things properly.

[gjh8733 in reply to GardNerd]

Thanks. Glad to know I have company! Will be interested to hear how quickly the dose reduction results in platelet cell count rebound

[johoho]

Hi there all, please excuse my ignorance, is Besremi the same as Inteferon? I'm in the UK and haven't heard of it. Thank you 😊

[gjh8733 in reply to johoho]

Hi there. Besremi is a once weekly interferon formulation. It’s approved for MPN in the US and I think in the EU.

[johoho in reply to gjh8733]

Thank you, my consent is looking into it. She hasn't heard of it either, I'm wondering if it's just a different name for the same Inteferon? I suppose I may find out today.

[marlenablue]

This was my experience on Besremi - all my blood counts dropped after 6 months at 500 mcg but my platelets dropped well below the low range of normal. I was taken off Besremi and it took a few months for the platelet counts to return to normal. I never went back on it. After a BMB, I found out my PV turned into MF and Besremi is not indicated for MF. My doctor suspected that conversion to MF was possible because of my high white blood cells count (16 -19,000), enlarged spleen and SF3B3 mutation. And well, here I am. By the way, my counts have returned to the levels that they were before Besremi, so I just had my first phlebotomy in over a year. I hope you find the sweet spot!

[gjh8733 in reply to marlenablue]

Thanks Marlenblue for sharing your experience. The platelet count returned to normal levels for me after a month - so good news. I am now on a dose of 100 ug/2weeks and will monitor over the next few months to hopefully find a sweet spot