Purpose of this Study
We are doing this study to find out if an experimental drug called lasofoxifene (the study drug) is a safe and effective option for breast cancer. We want to see if the study drug combined with another drug called abemaciclib has better results than treatment with abemaciclib plus fulvestrant.
Who Can Participate?
Eligibility
Adults ages 18+ who:<ul>
<li>Are diagnosed with estrogen receptor-positive (ER+) and human epidermal growth factor receptor 2-negative (HER2-) breast cancer</li>
<li>Have a documented ESR1 gene mutation</li>
<li>Have not received more than 1 line of chemotherapy in the past, and not more than 2 lines of treatment altogether</li></ul>
For more information about who can join this study, please contact the study team at breastcl@dm.duke.edu.
<li>Are diagnosed with estrogen receptor-positive (ER+) and human epidermal growth factor receptor 2-negative (HER2-) breast cancer</li>
<li>Have a documented ESR1 gene mutation</li>
<li>Have not received more than 1 line of chemotherapy in the past, and not more than 2 lines of treatment altogether</li></ul>
For more information about who can join this study, please contact the study team at breastcl@dm.duke.edu.
Age Range
18-89
Sex/Genders
Male (cisgender)
Female (cisgender)
Non-binary or gender fluid
Transgender male
Transgender female
Looking for Healthy Participants
No
What is Involved?
If you choose to join this study, you will get a random assignment (like a coin flip) to 1 of 2 groups:<ul>
<li>One group will get the study drug plus abemaciclib</li>
<li>The other group will receive fulvestrant plus abemaciclib</li></ul>
All study participants will:<ul>
<li>Have blood draws</li>
<li>Have heart scans (EKGs)</li>
<li>Have imaging scans</li>
<li>Answer questionnaires</li>
<li>Complete drug dosing diaries</li>
<li>Give us permission to store your tissue samples</li></ul>
After completing the study regimen, we will call you every 6 months to see how you are doing.
<li>One group will get the study drug plus abemaciclib</li>
<li>The other group will receive fulvestrant plus abemaciclib</li></ul>
All study participants will:<ul>
<li>Have blood draws</li>
<li>Have heart scans (EKGs)</li>
<li>Have imaging scans</li>
<li>Answer questionnaires</li>
<li>Complete drug dosing diaries</li>
<li>Give us permission to store your tissue samples</li></ul>
After completing the study regimen, we will call you every 6 months to see how you are doing.
Locations
Duke University Hospital
Duke Raleigh Hospital
Visit Timing
Weekdays
Compensation
Yes
Spanish Materials Available
No
Study Details
Full Title
An Open Label, Randomized, Multicenter Study Comparing the Efficacy and Safety of the Combination of Lasofoxifene and Abemaciclib to the Combination of Fulvestrant and Abemaciclib for the Treatment of Pre-and Postmenopausal Women and Men with Locally Advanced or Metastatic ER+/HER2- Breast Cancer with an ESR1 Mutation
Principal Investigator
Carey
Anders
Protocol Number
PRO00112602
NCT ID
NCT05696626
Phase
III
Enrollment Status
Open to Enrollment