All too often, patients who are diagnosed with MBC or whose cancer progresses are unaware of the treatment options available to them. Below is the list of FDA-approved treatments for HR+, HER2- postmenopausal women in the US. I finalized this list of treatments with a Medical Oncologist at Columbia Presbyterian Hospital in NY, and it is available (along with information about cutting edge MBC research, symptom and side effect mitigation, clinical trials, and more) in my book, "The Insider's Guide to Metastatic Breast Cancer" which is available as a paperback and eBook, and also a complimentary .pdf. For more information, you are welcome to visit: insidersguidembc.com/about
In the next week or two, I'll be posting treatment information regarding other MBC sub-types. I hope you find this helpful!
The sequence of providing hormonal (endocrine) therapy for postmenopausal, HR+ HER2- patients will vary, since much of it depends upon what - if any - hormonal therapy drugs the patient has previously taken and how recently they were takden.*
As per NCCN 2019 guidelines for patients in the US, there is a choice of taking single drugs or a combination of drugs, with combination drugs generally causing more side effects but potentially being more effective. Patients will want to discuss these options with their medical teams and check insurance coverage, since it’s possible that some of the combination drug regimens listed below may not be covered by the patient’s insurance, or they may be expensive.
First Line Hormonal and Targeted Treatment Options for Postmenopausal Patients in the US:
•An Aromatase Inhibitor (Letrozole [Femara], Arimidex [Anastrozole], or Aromasin [Exemestane]), either alone or in combination with a CDK4/6 inhibitor (Ibrance [Palbociclib], Kisqali [Ribociclib], or Verzenio [Abemaciclib])
•Faslodex (Fulvestrant) either alone or with a CDK4/6 inhibitor (Ibrance, Kisqali, or Verzenio)
•Faslodex with Arimidex A recent study (NCT00075764) reported that postmenopausal patients taking Faslodex and Arimidex as initial endocrine therapy had a median Overall Survival (OS) of 49.8 months compared with 42 months in the Arimidex-only arm, which is the longest ever reported for this type of patient. Therefore, this combination may be worth discussing with one’s doctor.
•Tamoxifen (Nolvadex) or Fareston (Toremifene) alone (rarely used as a first-line therapy).
Second Line Hormonal and Targeted Treatment Options for Postmenopausal Patients in the US depend upon what endocrine therapy had previously been taken:
•Possibly any of the above therapies.
•Afinitor (Everolimus) with either an Aromatase Inhibitor, Faslodex, or Tamoxifen.
•Verzenio alone (after disease progression on endocrine therapy and prior chemotherapy for MBC).
•Piqray (Alpelisib) in combination with Faslodex if the cancer has a PI3K mutation (more about this below).
Third and Fourth Line Hormonal and Targeted Treatment Options for Postmenopausal Patients in the US depend upon what endocrine therapy had been previously taken:
•Possibly any of the above therapies (although not all options are widely used in a third or later line setting).
•Either Ethinyl Estradiol, Megace (Megestrol Acetate), or Halotestin (Fluoxymesterone).
Chemotherapy is usually prescribed after endocrine therapies have stopped working, or a clinical trial may also be a consideration. Once the cancer has regressed or stabilized, it may be possible to go back on endocrine therapy if sufficient time has elapsed and if the initial response to endocrine therapy had been favorable.
DID YOU KNOW?
Patients with bone metastases should receive a bone-directed therapy such as Xgeva (Denosumab) or Zometa (Zoledronic acid) in addition to their other therapy.
If the patient’s cancer has progressed on first-line hormonal therapy and there is a PI3K mutation, then Piqray (Alpelisib) tablets along with Faslodex are an FDA-approved option. Piqray is a PI3K inhibitor that has shown a clinically meaningful benefit in treating patients with this type of breast cancer. A diagnostic test called “Therascreen PI3KCA RGQ PCR Kit” has been FDA-approved to detect the mutation in a tissue and/or a liquid biopsy. More information about Piqray is available in the chapter entitled, “Approved Therapies Based Upon Tumor Characteristics.”
Patients with inherited (“germline”) BRCA mutations may want to speak with their medical teams about taking a PARP inhibitor such as Talazoparib (Talzenna) or Olaparib (Lynparza), which are FDA-approved for HER2 negative MBC patients with BRCA mutations. Additional information is available in the chapter entitled, “Approved Therapies for Patients with BRCA Mutations.”
If a US patient’s cancer has microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) characteristics (which are very rare), and if the patient has progressed on prior therapy and has no satisfactory treatment options, Keytruda (a PD-1 inhibitor also known as Pembrolizumab), is an FDA-approved option. More information about Keytruda is provided in the chapter entitled, “Approved Therapies Based Upon Tumor Characteristics.”
If a US patient’s cancer has a Neurotrophic Receptor Tyrosine Kinase (NTRK) gene fusion without a known acquired resistance mutation, and if there has been progression on prior therapy with no satisfactory treatment options, Larotrectinib (Vitrakvi) - an oral tyrosine kinase inhibitor that acts as an "on" or "off" switch in many cellular functions – is an FDA-approved option. NTRK fusions are extremely rare, occurring in only about 0.5–1% of common cancers. Additional information is contained in the chapter, “Approved Therapies Based Upon Tumor Characteristics.”
*The above hormonal treatment options are recommended for patients who are not experiencing “visceral crisis” (severe organ dysfunction and rapid progression of disease). For patients who have visceral crisis, chemotherapy may be used straightaway to control the disease, after which hormonal therapy may be a viable option.