After 3.5 years of no evidence of disease on Ibrance/letrozole, my bone mets (and one breast tumor) progressed due to my cancer acquiring the ESR1 mutation. My original diagnosis was stage IV denovo, bone only. Never had high tumor markers until this progression started 6 months ago.
The progression is still bone-only, but now it’s in every part of my spine, both shoulders, both femurs, my whole ribcage, and my sternum. Nothing in lymph nodes. I was denied surgery, so I still have my breasts, and one of the tumors is growing again. We biopsied that tumor, and I’m still ER-positive.
We did the liquid biopsy (ctDNA test), and I’ve acquired the ESR1 mutation, which means I’m moving on to Orserdu (elacestrant). It’s so new, I can’t find much about it, which feels scary. I wanted to try Faslodex and Verzenio (the devil you know), but my oncologist was adamant that Orserdu is necessary since I have the ESR1. I guess this mutation makes certain types of hormone therapies useless, specifically aromatase inhibitors, which is what I was on.
Orserdu is in the same class as Faslodex (they’re both SERDs), but the study didn’t show any benefit to patients who did not acquire the ESR1 mutation.
Is anyone on Orserdu? If so, how has your cancer responded? I can only find a median of 3.9 months of progression free survival from the trials, which is discouraging and not helpful.
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MJ_Michigan38
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Testing for ESR1 will be my next step once my current treatment fails. Dana Farber did a study comparing Fulvestrant (Faslodex) to Elacsestrant. Elacsestrant was better with more time until progression. Additionally Elacsestrant could be given alone resulting in less side effects than combination therapies. Patients who were on CDK4/6 Inhibitors the longest and also had the ESR1 mutation did best starting at 12 months. The presentation is on YouTube. Around nine minutes in the Doctor talks about Elacsestrant. The whole presentation is excellent with an overview of all the new drugs in the pipeline. Lots to look forward to.
Thank you! This video was great. I’m surprised she said side effects were so minimal though. Nearly everyone in an Orserdu (elacestrant) group I joined complained of terrible nausea and vomiting. It’s good to see that not everyone had that reaction. Also reassuring to hear that some patients were still on it more than a year later. I heard median PFS was 3.9 months, which I found to be pretty disappointing, but if it could get me years, I’d be happier.
Based on the data from the Dana Farber study the odds are in your favor. The drug was just FDA approved on 2/17/23. You will be one of the early pioneers to use this drug. Happy to see you have a great doctor who is leading breast cancer oncology practices; you are in good hands. Praying you will have a nice long run. There is much to be excited about.
I have been on Orserdu for 3 months and just had my first scan which showed stable with some improvement. I will take that! Side effects are almost nonexistent for me and I feel so much better than I did on Ibrance.
Omg, that’s amazing!!! So happy for you, and I’m glad to hear no side effects. Thank you for sharing—I haven’t heard many positive things from the Orserdu Facebook group, and I was worried. It occurred to me that we’re more likely to be vocal when we’re suffering than when we’re feeling good. Thanks again for sharing, and I hope you continue to feel good with improvement.
Wish you the best - try not to let the stats get you down. This stat like nearly every one we read about will be overcome by many, many people. That stat only applied to the people in that study and it gives hope for progression free survival and delay of time before someone tells you chemo is your only option. When l was diagnosed 6 years ago l should have died - but here l am feeling blessed with my family and able to complain if l want to! Mary 🌺
I’m also on the FB group. There are under 200 members remember. And people tend to post in general when they have side effects. Plus people are only just now having their first scans.
That’s true, and I’m relieved to see some reporting more positive outcomes here. I think it’s just human nature that when we’re miserable, we talk more about it, probably because it feels good to know we’re not alone. And when we’re doing well, we’re not spending our time on forums. But I’ve vowed to let people know if I have good outcomes on this drug, so others aren’t scared off from trying it.
During my 3.5 years of progression-free time on Ibrance and letrozole, I didn’t participate much on the Facebook groups. I felt so sad for those who weren’t seeing the same good results, and I also felt depressed and discouraged, reading every day about the loss and grief. There certainly needs to be balance with hopeful stories, but while letting those who are suffering have a place to talk and grieve without forcing toxic positivity on them.
A really good FB group that has been a source of support for me is called: Metastatic Breast Cancer~An Honest Discussion About Living and Dying any positivity in this group has never felt 'toxic' at all, everyone there is supportive and non-judgemental about other people's decisions and some of my greatest support and helpful information has come from people who were experiencing progression or were in hospice.
I did not heave success on this medication. The side effects were worse than the cancer: muscle weakness, nausea; no appetite I was excited bc of the mutation but it wasn’t meant to. Br. Best of luck. Ellen n
this is my next line of Treatment. I am on Piqray. Am off due to C Diff infection. Nasty. reaction to an antibiotic. In quarantine for 10, days. Then to this drug. A challenge to keep positive. Reenie
I’ve heard Piqray is so hard. I’m sure adding a C-Dif infection to it is just icing on the cake. I find that, for me, when I can’t stay positive, it really helps to just be negative. I cry and vent and tell everyone around me how much I’m struggling. I don’t hide the challenges. The people who love me let me do this, and somehow, afterwards, I feel better, maybe even positive. There is so much pressure on cancer patients to be brave and cheerful and “inspirational,” but especially for those of us who can’t be cured, that is an unrealistic expectation. I hope this difficult time passes soon and that Orserdu becomes a good drug for you. It sounds like you’ve been through a lot. ❤️
Hi...I started on Orserdu in June and was wary of the side effects posted about the drug. I didn't have the nausea others have had. So far I have had 2 issues: 1) inability to sleep which while not specifically called out for this drug is an issue for this class of drugs so I now take 10 mg of Melatonin; 2) high cholesterol - my LDL has gone up alot so I'm expecting my doctor to start me on a statin. My doctor says that my marker numbers look good. I'm not due for a scan until Sept/Oct.
Thanks for your response! I started June 16th and have scans September 7th. Like you, I haven’t had the nausea/vomiting, which is such a relief. My cholesterol went way up. My baseline was “optimal” and now it’s very high without eating differently. Sigh…oh well.
I am also starting Orserdu after 18 mos on Ibrance/Faslodex. Progression to spine. I also now have ESR1 mutation. So I have the same concerns as you…. Let’s stay in touch.
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Sad update about ErSO 
Starting Ibrance and Letrazole next week
Faslodex and next steps
Starting Afinitor soon.
