New Methods of drug deliverance
- Isolated infusion methods
In some cases of melanoma, an isolated limb perfusion may be carried out. Sometimes chemotherapy is delivered as an isolated perfusion into the liver or the lung. The main aim of this mode of treatment is to deliver a very high dose of chemotherapy to the tumors without seriously affecting the normal cells in the body. This treatment is not effective in treating metastasized cancers.
- Targeted delivery mechanisms Specially targeted delivery vehicles aim to increase effective levels of chemotherapy for tumour cells while reducing effective levels for other cells. This should result in an increased tumour kill and/or reduced toxicity.
Specially targeted delivery vehicles have an increased affinity for tumour cells and interact with tumour-specific antigens. This method aims towards delivering the maximum effective dose to the tumor cells while reducing the toxic effect on the normal cells.
Nanoparticles are used as vehicles in delivering drugs that are not easily soluble, like paclitaxel. One such nanoparticle, Abraxane, won the approval of the FDA in January 2005 for treating refractory breast cancer.
A new method makes use of the bacterially - derived minicells that helps to selectively deliver a wide range of chemotherapy drugs to specific tumour cells, using bispecific antibodies. Cancer cells absorb the drugs through the process of endocytosis. This method is at the trial stage in humans.
Minicells are made up of a firm and stable biological membrane and therefore, do not carry the risk of getting destroyed. This minimises toxicity to the barest minimum.
Chemotherapy - References:
- MacDiarmid J.A. et al. (2007)
- "Bacterially Derived 400 nm Particles for Encapsulation and Cancer Cell Targeting of Chemotherapeutics" Cancer Cell 11, 431-445, May 2007