An Australian biotechnology firm said yesterday it had developed a means of delivering anti-cancer drugs directly to cancer cells, which aims to avoid the debilitating toxicity associated with chemotherapy.

The method uses nanotechnology, which involves micro-machines far smaller than a human cell.

Direct targeting of chemotherapy drugs would allow dosages thousands of times lower than that in conventional chemotherapy and be more easily tolerated by patients, said the firm.

Writing in the May issue of US-based Cancer Cell magazine, the biotech firm EnGeneIC said it had developed nano-cells containing chemotherapy drugs.

Via antibodies on their surface, these nano-cells target and latch on to cancer cells. Once attached, the nano-cell is engulfed and the drug is released directly inside the cancer cell.

The firm said the bacterially derived nano-cell, called EnGeneIC delivery vehicles, had proven safe in primate trials and resulted in significant cancer regression.

It hoped to carry out human trials later in 2007 if it gained approval from Australian, US, European and Japanese regulatory authorities.

"For the first time there is a real possibility that this technology could lead to the use of multi-drug combinations and eventual custom-made therapies in cancer patients," research scientist Jennifer MacDiarmid said in a statement.

"In terms of tumor therapy, most late-stage cancer patients carry tumor cells that exhibit various forms of drug resistance. Our technology may provide the first in-vivo (inside an organism) solution to this serious hurdle."

Gulf in cancer treatment

The use of modern cancer drugs can vary by a factor of 10 between different developed countries, while millions in Africa lack access even to basic pain relief, experts said yesterday.

Swedish researchers said there were "stark inequalities" in access to cancer medicine around the world, contributing to significant differences in patient survival rates.

The United States, France, Switzerland and Austria are the leaders in using new cancer drugs, while Britain, New Zealand, Poland, the Czech Republic and South Africa are laggards, according to an analysis of 67 medicines across 25 countries.

The biggest differences were seen in four new colorectal and lung cancer drugs Avastin, or bevacizumab; Erbitux, or cetuximab; Tarceva, or erlotinib; and Alimta, or pemetrexed.

The uptake of Avastin for colorectal cancer in the United States, for example, was 10 times the European average, as was the use of Tarceva in lung cancer.

These drugs belong to a new class of targeted therapies that are helping patients live longer, with fewer side effects.

Dr Bengt Jonsson, director of the Centre for Health Economics at the Stockholm School of Economics, said better access to such medicines was one reason why rates of survival from cancer were higher in France and Spain than in Britain.

Source: China Daily/Agencies