“The approval means that women with metastatic breast cancer no longer need to endure the toxicities associated with solvents and will no longer need steroid premedication when they receive this albumin-bound form of paclitaxel,” said principal clinical study investigator William J. Gradishar, M.D., associate professor of medicine, division of hematology/oncology at Feinberg and co-director, Lynn Sage Breast Cancer Program at Northwestern Memorial Hospital.
Gradishar is also a breast cancer researcher at The Robert H. Lurie Comprehensive Cancer Center of Northwestern University.
“In our research, participants who no longer responded to some of the more common treatments showed improvement with Abraxane and experienced less-severe side effects that made treatment more tolerable,” Gradishar said.
Abraxane is engineered using a proprietary process (protein-bound nanoparticle technology) to create tiny particles (nanoparticles 100th the size of a red blood cell) in which the active chemotherapeutic drug, paclitaxel, is bound to a naturally occurring protein called albumin.
By using this nanotechnology, the active component (paclitaxel) can be delivered into the body at a 50 percent higher dose over 30 minutes.
This contrasts with Taxol, in which paclitaxel is dissolved in a toxic solvent, which requires pre-medication with steroids and antihistamines to avoid hypersensitivity reactions and must be given in infusions for up to three hours.
Because Abraxane is solvent-free, solvent-related toxicities are eliminated and premedication is not required.
In the clinical studies, the response rate for all participants treated with Abraxane was almost twice that of participants receiving the solvent-based paclitaxel injection. Without toxic solvents, Abraxane could be given at higher doses than Taxol, which may account, in part, for the increased anti-tumor activity.
In addition, albumin is a protein that normally transports nutrients to cells and has been shown to accumulate in rapidly growing tumors. Therefore, Abraxane’s increased effectiveness may also be due to preferential delivery of albumin-bound paclitaxel to cancer cells.
Abraxane was developed by American Bioscience and will be marketed by Abraxis Oncology, a division of American Pharmaceutical Partners.