Phase: Phase II
ClinicalTrials.gov ID number: NCT03781063
Sponsor of the trial: Sermonix Pharmaceuticals LLC
Who is the trial for?
The ELAINE trial is for postmenopausal women diagnosed with locally advanced or metastatic estrogen-receptor-positive, HER2-negative breast cancer with an ESR1 mutation who have had the cancer grow while being treated with an aromatase inhibitor in combination with a CDK4/6 inhibitor.
The aromatase inhibitors used to treat breast cancer are:
- Arimidex (chemical name: anastrozole)
- Aromasin (chemical name: exemestane)
- Femara (chemical name: letrozole)
The CDK4/6 inhibitors used to treat breast cancer are:
- Ibrance (chemical name: palbociclib)
- Kisqali (chemical name: ribociclib)
- Verzenio (chemical name: abemaciclib)
Locally advanced breast cancer is breast cancer that has spread to tissue near the breast, but not to parts of the body away from the breast. Metastatic breast cancer is cancer that has spread to parts of the body away from the breast, such as the bones or liver.
The trial is looking to see if the medicine lasofoxifene will offer more benefits than Faslodex (chemical name: fulvestrant), a selective estrogen receptor degrader (SERD).
Why the trial is being done
Lasofoxifene is selective estrogen receptor modulator (SERM). Tamoxifen, Evista (chemical name: raloxifene), and Fareston (chemical name: toremifene) are other SERMs. The ESR1 gene is an estrogen receptor gene. When this gene mutates, it can make breast cancer resistant to hormonal therapies, including aromatase inhibitors. Earlier studies on animals have shown that lasofoxifene may be able to help treat metastatic breast cancers with an ESR1 mutation. Research suggests that 30% of metastatic breast cancers may have an ESR1 mutation.
The ELAINE trial is being done to see if lasofoxifene will improve progression-free survival more than Faslodex in postmenopausal women diagnosed with locally advanced or metastatic estrogen-receptor-positive, HER2-negative breast cancer with an ESR1 mutation.
Progression-free survival is how long a person lives without the cancer growing.
Lasofoxifene is a pill taken by mouth once per day. Faslodex is given once a month as two injections into a muscle.
Specific eligibility requirements
People are eligible for the ELAINE trial if they:
- are postmenopausal women
- have been diagnosed with locally advanced or metastatic estrogen-receptor-positive, HER2-negative breast cancer with an ESR1 mutation who have had the cancer grow while being treated with an aromatase inhibitor in combination with a CDK4/6 inhibitor
People are not eligible for the ELAINE trial if they have:
- had the cancer grow while being treated with Afinitor (chemical name: everolimus), or Piqray (chemical name: alpelisib)
- brain metastases
- been treated with radiation therapy within the last 30 days, except for women treated with radiation therapy to ease pain or for bone metastases that put them at risk for breaking a bone; the radiation must be completed 7 days before joining the study and women must have recovered from any radiation side effects before joining the study
- a history of a heart rhythm condition called long QT syndrome
- had a blood clot within the last 6 months; women who are taking blood thinning medicine and are stable are eligible for the study as long as any blood clot happened more than 6 months before they join the study
- uncontrolled high blood pressure
Potential side effects of the treatment being studied
In earlier studies, side effects of lasofoxifene were:
- blood clots
- hot flashes
- leg cramps
- thickening of the lining of the uterus
The ELAINE trial is being conducted at multiple sites around the United States. For a complete list of sites, visit the ELAINE ClinicalTrials.gov site.