I was successfully treated with Pegasus for ET. October 2025 the manufacturer didn’t have one component so I’ve been off for over a year now. My platelets are at 375, which my oncologist is very happy with!💕

This situation will come up now that Besremi is FDA approved for ET. I have been using Besremi for PV with thrombocytosis since 2022. I have been successful with Besremi due to using the low and slow approach. I gradually went up to 175mcg, which is my max tolerable dose. Fortunately, it is also an effective dose. HCT is staying under 45%. PLTs have dropped from the 500s-700s to under 200 at this dose. My JAK2 VAF has dropped from 38% to 12%,

It is from my view unfortunate that the label for ET calls for the HIDAT dosing strategy. The rapid titration from 250-350-500mcg would never have worked for me. Note that others are different in their needs and response to Besremi. While Besremi has been very effective for me, I strongly favor a more cautious approach to its use.

It is up to you in working with your hematologist to determine which dosing strategy you prefer. The questions I would ask are:
1. What is the appropriate target for platelets? Note that there is not a proven reduction in thrombosis risk targeting PLT<400 for most ET patients. Some docs use 600 when a number is used. Be sure to understand the rationale for the target you set. The actual goal is reduction in risk of thrombosis and hemorrhage.
2. Is there is a reason to be in a rush to meet the PLT target or can we be more patient?
3. What are acceptable parameters for the other blood cell values? You should expect a reduction in RBCs and WBCs, particularly at higher doses.
4. What are the acceptable parameters for liver and kidney function? This will be measured using a CMP.
5. How often will we be monitoring CBC and CMP during dose titration? The norm is every 2 weeks. How often will we monitor the molecular response to Besremi? My care team checks annually.
6. Be clear with your hematologist about your treatment goals, risk tolerance, and preferred treatment strategy. Note that quality of life goals are just as important as reducing the other risks of ET.

I have been very successful using Besremi. My MPN care team is committed to the Shared Decision Making Model, respecting my right to make care decisions. I am meeting treatment goals and my quality of life has improved using Besremi due to how we have managed its use.

Wishing you success moving forward.

Best wishes to all. We are all different. I have CALR ET. Couldn't tolerate Hydroxyurea side effects. Anagrelide controls my platelets with fewer side effects, except for mild diarrhea I've learned to control. I haven't tried anything else.
Specialists vary. My original hematologist thought platelets should be lowered to "normal range" (up to 450) and said there was no alternative to HU. My current hematologist (much preferred) wants to keep platelets "out of dangerous range," changed HU to Anagrelide, and made no med change when platelets were in 800's.
Surprisingly, my platelets suddenly dropped this year to high 400's, and have stayed there. This may be because overall inflammation was reduced by parathyroid gland surgery in May, which normalized my very high parathyroid hormone level. Surgery was by Dr. Masha Livhits at UCLA Endocrine Center. Nobody thought this would happen. People might want to ask their MPN doctors to have parathyroid hormone level checked during bloodwork. I don't know if other doctors will do that. I've felt much better since the May surgery. Another example of how people here deal with more than one health issue at a time.

Steve has some very good points. I agree with him on the low and slow approach. I was started on the standard start dose for Pegasys about 7 years ago. My body was "attacked" by week 8. I've spoke with others who experienced similar situations. Besremi has the same side effect profile as Pegasys. My MPN specialist has told me I'm not a candidate for either now. I would never subject my body to an interferon again. That being said, others do well on the treatment.

I just asked that question to my MPN specialist...Since I have been dealing with Microscoptic Colitis off and on for years, he does NOT recommend Besremi for me. One of the side effects is that it can cause Colitis along with a long of other issues.