I have been told if you change/reduce your dose of IBrance due to consistently low neutrophil counts, the oncologist cannot prescribe the higher dose again.
I have a different situation. I have been on 125mg for 7 months. I have had most of the common side effects (sore mouth, mouth sores, fatigue) with the addition of neuropathy in my hands & toes. However my neutrophils have been in the 0.9-1.0 range. Fine according to my oncologist. My PET scan came back as NED last week.
So I asked my Oncologist if we could move to 100mg next month so I can attempt to reduce the side effects & have a higher quality of life. I said if the next PET scan shows a change from NED, I would go back on the 125mg.
My oncologist said normally you can’t go back up if you go down in dose. I said but that is only for low neutrophils, right? He said yes. So can we give this a try? He reluctantly said yes.
After all the posts & articles I’ve read on IBrance efficacy being the same no matter the dose I feel this was a reasonable request.
Has anybody ever been prescribed a lower dose of IBrance & moved up to a higher dose? Any problems? Any pushback from your oncologist?
Thank you,
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I was on 125 for three months and was dizzy and so moved to 100. I have not moved back up and have been on 100 now for 37 months. But for the dizziness, my side effects didn’t change when I went to 100. I’m not sure why you’d want to go back up. If you were to progress, you’d move to another med. And my doctor says that there’s evidence that 100 is as effective. (PS. My neutrophils tend to be .8 - 1.)
I was changed to 100 mg after one month on 125 mg due to low neutrophils
However my oncologist is now pleased with my blood count and actually mentioned recently about putting me back on the higher dose...even though I’ve had progression in my liver....makes no sense to me...I refused anyway as I can more or less manage the side effects of the 100 dose so why suggest it I’ve no idea
I have found the same thing here in Canada. They are way too busy and make mistakes. Also, I feel they don't address every issue at our appointments because they simply don't have time to cover them. So I try to have as many questions ready as I can. Having said that I think they are doing the best they can under the circumstances. I agree we have to stick up for ourselves. Be our own advocate, is a favourite expression these here.
I've read that if the Ibrance works for you, it works no matter what the dosage. I went from 125 to 100 to 75 due to side effects and still have positive, stable scans for about 20 months. I'm also on a 5/2 schedule instead of 21/7. I've posted the following on here elsewhere, but if you haven't seen it, you might find it interesting. It's from another support site, and I've transferred it to a word doc and cleaned it up. It's long, but worth reading:
"1. I just had an appointment with my oncologist yesterday-- she told me that a Pfizer
representative told her recently that post-marketing analysis of both the earlier clinical trials and actual
patient use (data to be released in the future) is showing that ANY dose is equally effective-- that if it
works, it works, regardless of the dose, and there doesn't seem to be any correlation with degree or
duration of response based on dose.There will be more sub-group analyses reported in the next year or so trying to determine if a particular sub-group of patients (lobular vs ductal, ER+only vs both ER and PR+, etc...) responds better than others....
So I wouldn't be concerned about lowering the dose- I am almost at the end of cycle 32--the last 28 of
them at 75 mg. So it hasn't affected the effectiveness for me...and I will continue at this dose at least until my next scans in January.
One other thing to consider is a recommendation from a research pharmacist I talked with when I was
having difficulty with the higher doses and low WBCs/ANC-- he said, based on his knowledge of cancer biology and where Ibrance works in the cell reproduction process, it is his recommendation to take a lower dose for more days in a row and also minimize the amount of time off the medication, than to take a higher dose for fewer days or having longer days-off intervals.
Hope that you find that you get less side effects from the lower dose. May you dance with NED for years to come! "
and
2. "My onc, who is a researcher and has a wonderful team of scientists-- including pharmacists-- to work with, typically has a threshold of 2 cycles in a row either needing dose interruption due to a day 14 or day one WBC less than 2.7 or an ANC less than 0.8-0.9, or "time off drug" prolongation longer than a week (barring extenuating circumstances like surgery or some such thing).
She and her pharmacist feel that due to the average 29-hour half-life, prolonging the time off beyond 7
days is not as optimal as keeping on a consistent dose, even if it is a lower dose....however, they also
believe that once you have titrated down to 75 mg, if you are still getting a good clinical response but also still having those low blood counts, then shifting the dosing schedule around is definitely worth trying. Her pharmacist colleague (Sam, a lovely man!) says "There is no magic in the number 7", so you don't necessarily have to move to taking an entire second week o?, nor do you need to keep on a 21-day "on" cycle....he is a strong advocate for being creative, so long as you keep a few principles in mind:
Based on where Ibrance works in the cell reproduction cycle (and likely this holds true for
ribociclib/Kisquli, since it shares very similar CDK4 and CDK6 activity--abemaciclib has a slight different action profile and we never discussed it since it was long before it came to marker that we had our discussions)
* the time "on" Ibrance should always be longer than the time "off" the drug, and the longer "on" interval with the shortest "off" interval is the better choice (so, for example, 14 days on and 4 days off is better than 17 days on and 7 days off)
* due to the onset, duration of action and half-life of the drug, he suggests at least 10 days "on"is best to get meaningful benefit
* 2 days on and 1 day off for 21 days (or the 30 days you would have medication for on that regimen, then take some days off if needed based on your labs) is a very sound approach; he would not suggest ever going beyond every-other-day dosing; and he would prefer someone try every 36 hour dosing before they tried every-other-day. Other schedules could include 3 days on and one off or 4 on and 1 off
Also, please also keep in mind that there is NO data that suggests that people on a higher dose get a
better (regression vs stable disease) or longer response than people at a lower dose, so I would not be too reluctant to lower the dose based on undesirable side effects (low blood counts as well as fatigue, nausea, GI upset, mouth sores, etc). I know that I was very reluctant and unhappy when I had to go to
lower doses, but I certainly felt better and also was finally able to complete full cycles and start the next one on time, which ultimately is the best thing for suppressing the cancer cells. And now that I am more than 30 months (32 cycles) on it, I know that it is true that lower doses can be equally effective.
In fact, my onc believes that the lower doses may be more beneficial in the long run due to the lighter effects on the bone marrow, liver, kidneys and thus will allow my body to be in the best shape possible to deal with the cancer and the cancer medications for a long time. She says that it is well known that about 1/3 of cancer related deaths are due to the ultimate effects of the medications and not to the extent or action of the cancer at the time of death...so she almost always shifts doses around when possible to find the minimal effective dose for each patient in order to minimize the collateral damage to the body and it's organs.
Bonus is that many of her patients seem to have fewer or less serious side effects that is seen at the
So what is the point to give patient high dose and damage their organs. If the low dose work exactly has high dose they should start with the low dose first and then go up. However I find horrible that they are trying to force u to the high dose without trying the lower and then compromise our health. I try 125 mg but I felt like crap, so I request the lower dose. I felt tired but not like 125 mg was horrible and I took my supplements that help me alot and now I barely have side effects beside mild pain where I have my cancer lesion in my back.
I told my onc that fatigue was an issue , I have now been on ibrance for 8 Cycles. Last month she lowered my dose from 125mg to 100 because of the fatigue. She told me if the fatigue does not go down, we can go back up to the 125 milligrams. I am also on steroids for adrenal insufficiency, so she wanted to see if there is a difference, it's hard to tell if it's from the ibrance or the steroids. But yes she recommended that I go back up if the fatigue Remains the Same.
I started on 125 and head infection. This was 2015 when Drug was really new. Recent suspicion of possible progression prompted me to ask if I could go on 125 mg, which I did. Waiting for follow-up scans in December. Feeling great.
Well if MD Anderson does it, that is the best in the US, it’s good enough for me! Good to know. Glad you are feeling great! Wishing you good scan results. Thank you! ❤️🙏❤️
Why is the efficacy, in the different dosage, the same? Why put more/stronger drugs in our bodies, if the lower dose does the same??I started with the stronger 125 , August 2019, now on 75… due to low blood counts.
Then it sounds like my Anastrozole is doing the work… I hope Ibrance is more than just a “ Big Ticket Item “ Pfizer makes plenty of $$!
Dear Dflur: My understanding is that all the clinical trials on Ibrance were only done at the 125mg dose (typical for most clinical trials). The lower doses were created to help patients who had significant side effects from the drugs. Now that Ibrance has been prescribed for a good number of years, there is more evidence of patients still doing well on the lower doses.
There are many oncologists who are only comfortable prescribing what was tested in the clinical trial and that is why they are hesitant to lower the dose unless a patient exhibits the side effects specifically outlined by Pfizer on the Ibrance packaging.
Since all of our bodies are different, we react differently to the meds.
There is a big push to start testing multiple doses in clinical trials. Historically, it has been difficult to get enough qualified candidates participating in a clinical trial to test a multiple dose levels.
Whatever the dose, I’m glad Ibrance has been working so long for many of us.
Can't help on the actual question, but I have found some remedies for the side effects that might help. For the mouth sores, I dab a good quality tea tree oil directly into the sore (I use DoTerra Metaluca) and they are gone the next day. It tastes terrible, but it works. Also, I got my medical marijuana card, and take a 2:1 CBD/THC gummy and it really helps with the neuropathy.
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