The Phase II study, sponsored by American BioScience, included 106 patients with progressive metastatic breast cancer whose disease had progressed while being treated with TAXOL or Taxotere in the metastatic setting, or had a relapse within 12 months of adjuvant taxane therapy. The patients enrolled in this study had a very poor prognosis, with 91% having visceral (lung and liver) disease, 65% with more than three metastatic sites, and 88% demonstrating ongoing tumor growth while receiving TAXOL and/or Taxotere in the metastatic setting. Evidence of the activity of weekly doses of ABRAXANE in this highly refractory population is provided by the following findings:
- A 15% overall response rate (95% CI: 8%-22%) in the 106 patients studied with a 38% probability of survival at 12 months based on analysis of data to date;
- 40% of patients on treatment with ABRAXANETM were free of disease progression for as long as four months; and almost 30% for as long as six months;
- Of those patients who progressed while on Taxotere alone in the metastatic setting (n=33), a 24% response rate was noted after receiving weekly ABRAXANETM;
- Of those patients who progressed while on TAXOL alone in the metastatic setting (n= 31), a 16% response rate was noted after receiving weekly ABRAXANE.
"The demonstration that 15% of patients responded to ABRAXANETM treatment and that 30% had no disease progression after six months in this highly refractory breast cancer population that had progressed even while on TAXOL and/or Taxotere is an important finding. I think this drug has significant potential to benefit women with breast cancer," said Edith Perez, director of the breast cancer program at the Mayo Clinic in Jacksonville, FL.
The tolerability of this weekly regimen was demonstrated by the finding of <1% grade 4 febrile neutropenia and no grade 4 non-hematological toxicities. Grade 3 taxane associated toxicities were few, with <4% Gr3 sensory neuropathy, <3% Gr3 fatigue, <1% Gr3 edema, no Gr3 nail changes, no Gr3 myalgia and arthralgia, <1% Gr3 tearing, and no Gr3 hypersensitivity or flushing.
"I was very impressed not only by the activity of this drug but also by how well this weekly regimen of ABRAXANE
"This biologically interactive nanoparticle, through its novel albumin receptor-mediated mechanism of action, provides an opportunity to realize the full therapeutic potential of chemotherapeutic agents, while minimizing the drug's side effects, in the treatment of solid tumors. ABRAXANE, an albumin-bound nanoparticle form of paclitaxel, represents the first clinical proof of principle of this technology," said Patrick Soon-Shiong, M.D., Chairman, President and Chief Executive Officer of American Pharmaceutical Partners. "Our ultimate objective is to maximize the efficacy potential of chemotherapy including taxanes in cancer therapy – one of the most active anti-cancer agents discovered to date. However, due to the toxic solvents in current taxane preparations, the maximum dose that can be administered is limited. This may have significant implications on the course and ultimate outcome of treatment. If the active drug could be delivered to the tumor at the highest possible dose and for a long duration with the least amount of damage to normal tissue, the possibility exists that outcomes could be significantly improved.
"Recent studies have indicated that dose reduction during chemotherapy regimens may result in significant impairment of clinical outcome. The solvents used in currently approved taxanes contribute significantly to the toxicities of these drugs with resultant dose delays and reductions. By developing a nanoparticle form of a drug using a naturally–occurring human protein we have overcome the need for toxic solvents. The tolerability of this nanoparticle form was evident by the finding that 95% of cycles were given at the protocol specified dose of 100 mg/m², and that 91% of the patients were able to receive 100% of the planned dose of ABRAXANE at 100 mg/m2 administered weekly over 30 minutes with no dose reduction. Further, no grade 4 non-hematological toxicities and no severe hypersensitivity reactions, despite the absence of steroid pre-medication, occurred," said Soon-Shiong.
The company previously announced along with American BioScience Inc. that the New Drug Application (NDA) for ABRAXANE
About Breast Cancer
According to the American Cancer Society (ACS), while early detection efforts have decreased mortality rates, in 2004 an estimated 215,990 women are expected to be diagnosed with breast cancer that had already spread. Breast cancer is still the leading overall cause of cancer death in women between the ages of 20 and 59, with 40,110 deaths estimated in 2004. One of every three cancers diagnosed in the United States is breast cancer; excluding skin cancer, breast cancer is the most common cancer among women.
About the Companies
American BioScience, Inc. is a privately held biotechnology company focused on the discovery, development and delivery of next-generation therapeutic moieties including biologically active molecules already existing within the human biological system, for the treatment of life-threatening diseases. American Pharmaceutical Partners, Inc. is a majority owned subsidiary of American BioScience, Inc.
American Pharmaceutical Partners, Inc. is a specialty drug company that develops, manufactures and markets injectable pharmaceutical products, focusing on the oncology, anti-infective and critical care markets. APP has acquired the exclusive North American rights to manufacture and market ABRAXANE
Statements contained in this press release, which are not historical facts, are forward-looking statements, as the term is defined in the Private Securities Litigation Reform Act of 1995. Such forward-looking statements, whether expressed or implied, are subject to risks and uncertainties which can cause actual results to differ materially from those currently anticipated, due to a number of factors, which include, but are not limited to, the impact of pharmaceutical industry regulation, the difficulty in predicting the timing or outcome of product development efforts and FDA or other regulatory approvals or actions including the approval of ABRAXANETM, the impact of competitive products and pricing, the availability and pricing of ingredients used in the manufacture of pharmaceutical products, the ability to successfully manufacture products in a time-sensitive and cost effective manner, the acceptance and demand of new pharmaceutical products, the impact of patents and other proprietary rights held by competitors and other third parties, actual results achieved in further Phase II and III trials for ABRAXANETM may or may not be consistent with results achieved to date, the timing and completion of the ABRAXANETM filing, the fact that the FDA has not reviewed the Phase III data and may not grant approval on the basis of such data, and other risk factors discussed in the Company's Form 10-K and other documents filed by the Company with the Securities and Exchange Commission from time to time. These forward-looking statements represent the Company's judgment as of the date of this press release. The Company disclaims any intent or obligation to update these forward-looking statements.
TAXOL is a registered trademark of Bristol-Myers Squibb Company.
Taxotere is a registered trademark of Aventis.