A Phase 1-2, XIAP Antisense AEG35156 With Weekly Paclitaxel in Patients With Advanced Breast Cancer

Breast cancer is the most common cancer in women in the United States, the second most common cause of cancer death, and the main cause of death in women ages 45 to 55. In 2006, 212,920 American women will be diagnosed with breast cancer, and 40,970 will die from this disease.\[1\]. Fewer than 10 percent of women present with metastatic disease at the time of diagnosis. However, the majority of women who relapse after initial definitive therapy for early stage or locally advanced disease will do so with disseminated metastatic disease rather than an isolated local recurrence. Treatment for metastatic disease is palliative in intent and will usually involve hormone therapy and/or chemotherapy with or without trastuzumab. Active chemotherapy agents include anthracyclines, taxanes, vinorelbine, alkylating agents and antimetabolites. Taxanes have become the cornerstone of first-line treatment for metastatic breast cancer. Weekly doses of paclitaxel can be administered continuously for several weeks with a remarkable lack of myelosuppression \[2\]. Weekly paclitaxel (80 mg/m2) was directly compared to every three-week therapy (175 mg/m2) in 585 women with metastatic breast cancer. Weekly therapy was associated with a significantly higher response rate (40 versus 28 percent) and longer TTP (nine versus five months), but similar overall survival and worse neurotoxicity \[3\]. Since patients with metastatic breast cancer are unlikely to be cured of their disease \[4\], they should be considered candidates for a clinical trial.