Some interesting and innovative technology for cancer treatments comes from San Diego-based Inovio Biomedical Corporation. The company is working on bringing products based on its proprietary electroporation therapy to the market.
Inovio reports on how the therapy is thought to work in concert with bleomycin chemo:
Two decades ago researchers discovered that briefly applying an electric field to a living cell causes a transient permeability in the cell’s outer membrane. This permeation is manifest by the appearance of pores across the membrane. After the field is discontinued, the pores close within minutes without significant damage to the exposed cells and with the therapeutic molecules trapped inside the target cells. The phenomenon is known as electroporation from the words electric and pore. Electroporation Therapy has significant potential for the delivery of large molecules into cells…
Bleomycin is a well-established anti-cancer drug which is approved for use in humans in most countries of the world. When administered conventionally by injection or infusion it is not particularly effective in the treatment of malignant tumors. However, when a patient is treated with Bleomycin (intratumorally or systemically) and the tumor is exposed to electroporation, the efficacy of the drug is increased significantly. In vitro, electroporation has been shown to enhance tumor cell killing up to 5,000-fold. This increase in efficacy is based on the ability of electroporation to form temporary “pores” in the cell membrane, which allows Bleomycin to efficiently enter the cell. When the pores close again within seconds or minutes, the drug is trapped inside the cell and acts catalytically to destroy the cancer cell’s nucleic acids. Inovio has shown that tumors injected with bleomycin retain the drug in their cells much longer when electroporated, compared with non-electroporated tumors.
The goal of chemotherapy is to kill cancer cells with high efficiency, while keeping toxic side effects as low as possible. The enhancement of Bleomycin efficacy by electroporation allows to use relatively low doses of the drug locally, thus reducing the side effects to the point of no concern. Inovio’s standard treatment dose is 1 unit of Bleomycin per cm3 of tumor. For most tumors this dose will be well below the dose which would be given during conventional treatment, and well below the recommended maximal lifetime dose of 400 units.
Bleomycin has proven to be the most effective drug in combination with electroporation. Among over 20 chemotherapeutic drugs tested in a broad variety of tumors, with and without electroporation, the combination of Bleomycin and electroporation was consistently more effective than any other drug or drug-electroporation combination.
Inovio believes that its electroporation technology one day might also be used for a wide variety of other uses such as DNA delivery for gene therapy or DNA vaccinations, for ex vivo applications, for transdermal delivery for cosmetics, dermatology, and many other uses.
More at Inovio…
