71 year old female diagnosed 6 month ago with PV.

Sounds like the Hydroxyurea is working. A test for the JAK2 gene is just a blood test. If that's found then there is your cause.

Hi @jeanette1954 A diagnosis of Polycythemia Vera (PV) usually indicates that the person has an underlying blood condition, one from a group of blood cancers called MPNs (myeloproliferative neoplasms). These diseases generally cause an overproduction of one type of blood cell. In your case of PV, it’s too many red blood cells.
Quite frequently, the cause is from a mutation on a specific gene in the body. These mutations aren’t inherited but can develop over our lifetime. In the case of PV, often, as @maine mentioned in their comment, a mutation with the JAK2 gene is culprit. JAK2 regulates cell production. When there is specific mutation in that gene it bypasses the OFF switch allowing for continued production cells (red blood cells for PV)

Once this mutation occurs, there is no reversal. The only way that’s possible is to acquire an entirely new bone marrow chemistry (bone marrow transplant) and that’s not a first line treatment for PV. While there is no ‘cure’ for PV it is treatable by controlling the overproduction of cells with medications such as hydroxyurea, Besremi (interferon) or targeted Janus Kinase inhibitors, such as ruxolitinib.

The goal of treatment for PV is ongoing disease control. So while the hydroxyurea (HU), aspirin and phlebotomies are treating your symptoms, the HU is also helping to control the overproduction of cells.

A bone marrow biopsy isn’t required to diagnose PV but usually somewhere in the lab results there would be reference to having a genetic test run. Do you recall having seen reference to the JAK2 or other mutation?

I do have the Jak2V617F mutation. You explained alot to me and thank you. I'm happy to hear that the HU helps control production of overactive cells. Have you heard if Besremi helps shut the down the over active gene?

My hematologist said that besremi may have the potential to shut down the jak gene. I use all the qualifiers because this is very early research. I do know that my lab counts returned to normal one month after starting the drug. I am very sensitive to the drug and on a very low dose. There are some side effects but I am trying to tough it out. They do seem to be decreasing.

@jeanette1954 From information I’ve gleaned over time, from my understanding HU can help to control the over production of red blood cells in PV. But it doesn’t target the mutated JAK2 Gene. Whereas Besremi may help shut down the overactive gene and is considered a potential disease-modifying treatment.

Digging through my materials I found this article. I’m not sure how credible a source it is but the information correlates with other articles I’ve read. This one from Linked-in actually compares 3 medications other than Hydroxurea. If for nothing else it will give you an overview of other treatments.
https://www.linkedin.com/pulse/exploring-future-polycythemia-vera-treatments-besremi-himanshu-mason-14p3e
We also have other members in Connect who have had questions about switching to Besremi. @eferret posted this discussion a couple of years ago.

~After 3 months on hydroxyurea, I am going to ask to switch to Besremi
https://connect.mayoclinic.org/discussion/after-3-months-on-hydroxyurea-i-am-going-to-ask-to-switch-to-besremi/
You might want to read through the conversations and tag members there.

Have you discussed the possibility of changing meds with your doctor?

I can offer my experience/journey with PV so far… I’m female, 58 and was diagnosed in 2021. GP noticed levels started to elevate after looking at my yearly bloodwork. She recommended I see a hematologist. I tested positive for the JAK2 mutation. Hematologist ordered a battery of tests which included full body scans (to check if clots) etc., and a bone marrow biopsy. After these tests she immediately ordered phlebotomy treatments every so often, plus daily baby aspirin for platelet viscosity. After years of phlebs, veins can no longer handle it (veins collapsed), so we discussed other ways to keep numbers in check. She pushed for oral chemo such as Hydroxyurea but I declined and suggested Besremi (ropeginterferon) instead. I’ve been on it for almost 3 years. I’m low risk (never had heart attack/stroke) and no family history/personal history of depression or anxiety, and am otherwise healthy, so I was given clearance to take it. It has worked great so far - a positive hematologic response - all levels (WBC, RBC, plates) are normal after about two years of self-injecting every two weeks at a 150mcg dose. I have not needed a phlebotomy since June 2025. But it does have some side effects like a bad and daily case of raynaurds - apparently, Besremi can worsen any underlying auto-immune condition. But overall, I’m satisfied with the results - it’s stopping disease progression!

I'm considered high risk based on age only, as I have no history of thrombosis. Will definitely ask about Besremi at my upcoming MD appt. Your story is so encouraging and I wish you well.

Thank you for sharing this information. Definitely bringing up Besremi at next MD appt.

@holbrop Could you share what the side effects are?

I’m a 72 year old male and I was diagnosed with PV five years ago. Started out with frequent phlebotomies and various doses of hydroxyurea.
Once the appropriate dosage was determined I was able to quit the phlebotomies. I’m currently taking 500mg 4/week. My numbers are now very stable. I’ve had no negative reactions to the hydroxyurea since I started it.