Abraxane, first in a new class of albumin-bound nanotechnology for the treatment of metastatic breast cancer

Thirty-eight US Oncology, Inc. affiliated medical centers nationwide continue to play a significant role in the clinical research of Abraxane that was approved today by the U.S. Food and Drug Administration (FDA). Abraxane (paclitaxel protein-bound particles for injectable suspension), a next generation taxane, and the first in a new class of albumin-bound nanotechnology, was approved for the treatment of metastatic breast cancer.

US Oncology conducted a phase 2 clinical trial of Abraxane in patients with metastatic breast cancer who were resistant to taxane drugs and continue to participate in the ongoing clinical development of the drug. Clinical trials of Abraxane have shown that the new drug is superior to solvent-based paclitaxel (commonly marketed as Taxol) in response rate and time to tumor progression.

"Abraxane is a significant advance in how paclitaxel is delivered and provides a much-needed new option for breast cancer patients," said Joyce A. O'Shaughnessy, M.D., co-director, US Oncology Breast Cancer Research, and director, Breast Cancer Prevention, at Baylor-Charles A. Sammons Cancer Center in Dallas, Texas. "With this human protein nanoparticle form of paclitaxel, patients no longer require steroid premedication to avoid the sometimes life- threatening allergic reactions which occur with current solvent-based paclitaxel therapy." "In our trials with weekly Abraxane, we saw fewer side effects than observed with solvent-based paclitaxel, and, even more encouraging, we saw a significant response to Abraxane in some women whose cancer had progressed through treatment with taxanes. Women taking Abraxane also spent less time in the clinic receiving their chemotherapies," said Joanne Blum M.D. who was the principal investigator of the US Oncology clinical trial of Abraxane.

To date, the formulation of insoluble tumor-fighting agents, such as paclitaxel, has required the use of solvents which, in addition to other side effects, cause severe allergic reactions called hypersensitivity reactions. For instance, in Taxol, paclitaxel must be dissolved in the solvent Cremophor- EL so that it can be administered to patients. To reduce the risk of allergic toxicities when receiving Taxol, patients must undergo premedication using steroids and anti-histamines and be given the drug using slow infusions.