Sanofi-aventis and its wholly-owned subsidiary, BiPar Sciences, have announced that the clinical development program in metastatic triple-negative breast cancer (mTNBC) for the investigational PARP1 inhibitor, BSI-201, progresses as planned with the Phase 3 study meeting expectations on patient accrual and trial site coverage in the US. Study investigators have enrolled 214 of the target number of 420 patients.
BSI-201 entered a Phase 3 clinical trial in the US in July 2009 and is being evaluated in combination with chemotherapy in patients with mTNBC, a condition defined by tumors lacking expression of estrogen, progesterone receptors and without overexpression of HER2. BSI-201 is a investigational targeted therapy that inhibits poly (ADP-ribose) polymerase (PARP1).
The decision to commence with the Phase 3 study in July was based on the Phase 2 study results presented at ASCO on May 31, 2009. In the Phase 2 clinical trial, women with mTNBC who were randomly assigned to receive gemcitabine and carboplatin (GC) in combination with the investigational agent BSI-201 or GC alone. Updated Phase 2 data, including overall survival, were presented at a poster session at the 32nd Annual San Antonio Breast Cancer Symposium (SABCS).
The addition of BSI-201 to GC improved median overall survival from 7.7 months to 12.2 months. (HR=0.5, p=0.005). BSI-201 did not add to the frequency or severity of adverse events associated with chemotherapy. This is not a final analysis of the Phase 2 data, but rather an updated analysis of
overall survival. Median survival has not yet been reached in the BSI-201 arm, therefore the data cut-off period for the Phase 2 trial from September to November.
Marc Cluzel, executive vice president of R&D at Sanofi-aventis, said: “The updated analysis from the Phase 2 program, including data on overall survival, are consistent with the positive results presented earlier this year at ASCO. We are very encouraged by the fast recruitment of patients in Phase 3 trial. We hope the findings will lead to emerging strategy that may help women with metastatic triple negative breast cancer.”
The FDA granted Fast Track designation to BSI-201 for mTNBC.