A Phase II Randomized Study of Paclitaxel Versus Paclitaxel + PSC833 for Advanced Breast Cancer (Recurring Less Than 6 Months Since Adjuvant or as Second Line for Advanced Disease
OBJECTIVES: I. Evaluate the response rate and time to treatment failure of paclitaxel with
and without the P-glycoprotein (Pgp) antagonist PSC 833 in advanced breast cancer. II. For
each treatment arm, relate paclitaxel AUC (area under curve), and/or time above .05 um/L, to
myelosuppression and/or response. III. To obtain preliminary estimates of MDR in this group
of patients by measuring MDR1-Pgp immunostaining in pretreatment biopsies in 20 patients and
biopsies taken at the time of progression.
OUTLINE: This is a randomized study. Patients are stratified according to three criteria: 1)
treatment within 2 years of adjuvant chemotherapy vs. progression on chemotherapy for
advanced disease 2) measurable vs. evaluable disease 3) institution. Patients receive
paclitaxel alone or paclitaxel plus PSC 833. In the first arm, paclitaxel alone is
administered by continuous infusion over 3 hours once every 3 weeks. In the second arm, PSC
833 is administered PO four times a day for 3 days; paclitaxel is administered by continuous
infusion over 3 hours on day 2. Courses repeat every 3 weeks.
PROJECTED ACCRUAL: Approximately 70 patients will be accrued per year in this study.
Allocation: Randomized, Primary Purpose: Treatment
James H. Doroshow, MD
Beckman Research Institute
United States: Federal Government
|USC/Norris Comprehensive Cancer Center||Los Angeles, California 90033-0800|
|Beckman Research Institute, City of Hope||Los Angeles, California 91010|
|University of California Davis Cancer Center||Sacramento, California 95817|