The Breast Cancer International Research Group (BCIRG) and the Sanofi-Aventis group announced the results from the first interim efficacy and updated safety analyses from the BCIRG 006 phase III breast cancer study, which show that trastuzumab(Drug information on trastuzumab) (Herceptin) combined with docetaxel(Drug information on docetaxel) (Taxotere)-based regimens significantly improved disease-free survival for women with early HER2-positive breast cancer. These data were presented at the 28th annual San Antonio Breast Cancer Symposium (SABCS) in San Antonio, Texas.
Survival Benefit Confirmed
Cardiac and global safety data together with the interim efficacy analysis based on 322 events were reviewed by an independent data monitoring committee. The relative reduction in the risk of relapse was 51% (95% confidence interval [CI] = 35%-63%, P < .001), and 39% (95% CI = 21%-53%, P < .001) for the doxorubicin(Drug information on doxorubicin)/cyclophosphamide followed by docetaxel/trastuzumab (AC-TH) and docetaxel/carboplatin/trastuzumab (TCH) arms, respectively, when compared to the control arm of doxorubicin/cyclophosphamide followed by docetaxel (AC-T). There was no statistically significant difference between the two trastuzumab-containing experimental arms. Overall survival data are not yet mature.
"These results confirm, that in this trial, a disease-free survival benefit was seen in the adjuvant setting with the addition of Herceptin to either of two Taxotere-containing chemotherapy regimens, with or without doxorubicin, in this poor-prognosis population of women with HER2-positive breast cancer," said Dennis Slamon, PHD, MD, cochair of the BCIRG 006 study and director of clinical and translational research at UCLA's Jonsson Comprehensive Cancer Center. "Moreover, additional molecular studies in patients from the BCIRG 006 study identified a subgroup (approximately 35%) of HER2-positive patients receiving Herceptin which may have a superior response to doxorubicin-based vs non-doxorubicin-based therapies."