TBCRC 007: A Phase II comparison and effectiveness study of medroxyprogesterone acetate (MPA) alone or in combination with low-dose chemotherapy in postmenopausal women with hormone receptor negative (HR-), metastatic breast cancer (MBC)

Back to Summary of Results

 

Purpose of the Study: 

Medroxyprogesterone acetate (MPA) was used for many years in women whose cancer was fueled by estrogen production.  This type of breast cancer is referred to as hormone receptor positive (HR +). Recent laboratory studies suggested MPA may be effective in treating patients who are hormone receptor negative (HR-) meaning estrogen does not make their breast cancer grow. This phase II trial was conducted to evaluate the activity of MPA alone or in combination with low-dose chemotherapy in patients with metastatic, hormone receptor negative (HR-) breast cancer.

Sponsor: 

Translational Breast Cancer Research Consortium (TBCRC)

Participating Sites: 
  • Dana-Farber/ Harvard Cancer Center
  • Duke University Medical Cancer Center
  • Indiana University Simon Cancer Center
  • University of Alabama, Birmingham
  • University of California, San Francisco
  • University of North Carolina, Chapel Hill
Start Date & Stop Date: 

Date First Site Activated: September, 2006

Date Trial Closed to Enrollment: July, 2010

Key Eligibility Requirements: 
  • Hormone Receptor negative (HR-)
  • Post-menopausal
  • No more than three prior chemotherapy regimens for metastatic disease
  • ECOG Performance status < 2
  • Adequate organ function
  • No blood clot within the last 12 months
  • No extensive fluid in the chest or abdomen
Study Design: 
  • Eligible women were assigned as follows:
    • Group 1 - MPA alone group
    • Group 2 - MPA with low-dose chemotherapy group
  • Each group would initially enroll 15 patients.
  • If less than two of the 15 patients had clinical benefit, that group would close.
  • If 2 or more patients had clinical benefit, an additional 10 patients would be enrolled to that group.
  • Blood samples and skin biopsies were collected to measure MPA concentration and the effect of MPA on markers of metastasis and blood vessel growth
Results: 
  • 30 patients were enrolled.
    • 14 were treated with MPA alone
    • 16 were treated with MPA in combination with low-dose chemotherapy.
  • There were no measurable responses in either group.
  • Five patients had stable disease but disease control was maintained for > 6 months in only 2 patients.
  • The MPA concentration achieved in our study was much less than anticipated and in most patients was less than the levels needed for activity based on the laboratory studies.
  • The markers of metastasis and new blood vessel formation didn’t change consistently.
Next Steps: 
  • MPA monotherapy had little clinical or biologic activity in patients with advanced HR-negative (HR-) metastatic breast cancer in this study.
  • Despite real-time assessment of MPA through concentration and mid-cycle dose increase, few patients reached concentrations in the potentially therapeutic range.
  • Though MPA will not continue in clinical trials, lessons from this trial will impact the design of future studies.
Scientific Publications Available for this Clinical Trial: 

Vaughn,L.G., Li, L., Nabell, L., Rugo, H.S., Carey, L.A., Kimmick, G.G., Steeg, P.S., Miller, K. A phase II study of medroxyprogesterone acetate (MPA) in patients (pts) with hormone receptor-negative (HR-) metastatic breast cancer (MBC): Translational Breast Cancer Research Consortium trial 007. 2010 ASCO, Poster, Abstract #1074.

Miller,K.D., Althouse,S.K., Nabell, L., Rugo, H., Carey, L., Kimmick,G., Jones, D.R., Merino, M.J., Steeg, P.S. A Phase II Study of Medroxyprogesterone Acetate in Patients with Hormone Receptor Negative Metastatic Breast Cancer: Translational Breast Cancer Research Consortium Trial 007. Breast Cancer Res Treat 148 (1): 2014.

*This summary was reviewed by: Kathy Miller, M.D.  This summary was also reviewed and approved by the members of the TBCRC Patient Advocate Working Group.