Preset drugs provide maximum benefits

Chemists at Aberdeen University have joined forces with a bioscience company to develop a new way of delivering drugs and vaccines which could cut down on injections and improve healthcare in the third world.

Quadrant, a research and development company in Cambridge, has devised a system whereby drugs with a short shelf life become stable at room temperature, and can be preserved indefinitely. Aberdeen is using its expertise in solid state chemistry and drug encapsulation to design a means of allowing the release of controlled doses at preset times.

Don Fox, director of Auris Research, the university's technology transfer company, said: "The important thing about these technologies is that they are not specific to any drug or condition. They can adapt to almost any circumstances, and different ways of delivery, such as by mouth or injection."

The drug could be steadily released over a period of days or weeks, Dr Fox said, and the Aberdeen scientists believed they could also develop a pulse release, operating, for example, at weekly intervals.

"It can increase the effectiveness of existing drugs, since with most, you just take them, and the rate at which they are absorbed depends on normal bodily processes," he said. "This can be modified to spread out the time over which the drug is released into the body."

The technology could lead to the elimination of booster jabs, and be used to vaccinate infants against common childhood diseases with a single injection of a dry, stable cocktail of vaccines.

The technology could be particularly useful in combating tropical diseases, Dr Fox said. Health workers might only visit certain areas sporadically, and could not depend on having refrigerators to keep unstable vaccines at a low temperature. But the new system would mean vaccines could be preserved without refrigeration, and patients could get the maximum protection from a single inoculation.

Clinical trials are likely to begin in around two years. "But we know enough about the chemistry and biology to be fairly confident that the components we're using are non-toxic and biodegradable, leaving no trace in the body," Dr Fox said.

The Aberdeen system could also have environmental implications, since it could potentially be used to control the release of pesticides, reducing the total amount used, and ensuring higher concentrations where and when these were needed, he said.

Auris and Quadrant say there are exciting commercial prospects in this area, with various estimates placing the size of the market for alternative drug delivery systems at between $7 billion and $10 billion. This figure is expected to increase threefold by the end of the century.