The Breast Cancer International Research Group and French drugmaker Sanofi-Aventis have unveiled the first interim results a Phase III clinical trial, which shows that two Taxotere (docetaxel)-based chemotherapy regimens in combination with Genentech’s Herceptin (trastuzumab) significantly improved disease-free survival in patients with a form of early-stage breast cancer.

The study, dubbed BCIRG 006, enrolled more than 3,200 women who had undergone surgery to remove their tumour and who were given various combinations of the anthracyclines doxorubicin and cyclophosphamide, Taxotere and Herceptin. Results showed the risk of relapse was more than halved for the anthracyclines/Taxotere/Herceptin regimen (51%), with a 39% decrease in the non-anthracycline arm, in which patients received Taxotere/carboplatin and one year of Herceptin.

Commenting on the findings, Dennis Slamon, PhD, MD, co-chair of the BCIRG 006 study, noted that “in this poor prognosis population of women with HER2-positive breast cancer, the interim efficacy analysis of BCIRG 006 study conducted after 23 months of median follow up, demonstrates that the addition of Herceptin to two Taxotere-containing chemotherapy regimens, with or without anthracycline, significantly improved disease-free survival in the adjuvant setting.” He added: “in the first interim analysis, this novel regimen of Taxotere without anthracyclines appears to avoid the problem of increased cardiotoxicity that has been reported when Herceptin is used together with anthracyclines.”

According to the American Cancer Society, 211,240 women will be diagnosed with breast cancer and around 40,000 will die of the disease in the USA this year. In the European Union, over 191,000 new cases are diagnosed each year with more than 60,000 mortalities as a result. Between 20%-25% of women with breast cancer will have the HER2-positive form of the condition.

The news is likely to broaden the market yet further for the cancer drugs, which are already big selling agents. Sanofi-Aventis reeled in some 764 million euros, up 11%, for Taxotere during the first half of the year [[19/07/05c]], while Herceptin also scored well for European partner Roche, with first half sales of 851 million Swiss francs, up 27% [[20/07/05a]]. Genentech recorded second quarter sales for Herceptin of $152 million, a rise of 29% [[12/07/05a]].