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Ceramic coat makes AIDS drug more efficient

Ceramic coat makes AIDS drug more efficient AN INDIAN-born biologist, Prafulla K Bajpai, and his colleagues at the University of Dayton, Ohio, have developed a novel drug delivery system that will bypass the harmful side-effects of AZT -- the primary drug used in AIDS treatment.

AZT, which is usually taken orally as pills, causes swollen tongues, bleeding gums, mouth ulcers, several gastrointestinal problems and suppressed production of bone marrow leading to anaemia. In Bajpai's method, ceramic capsules containing AZT will be planted under the patient's skin to deliver the drug in a sustained and in vivo (inside a living organism) environment.

Ceramic delivery will not only require lower AZT dosage, but could also prevent the usual side-effects because it eliminates the large fluctuations in drug concentration in the bloodstream and tissues. "With the ceramic capsules, you are always within the therapeutic range and there is no wastage of the drug," says Bajpai. This could prove a boon to AIDS patients for AZT treatment currently costs about US $3,000 annually. If Bajpai's system proves effective in human beings, the dosage could be cut by 5 to 10 per cent to achieve the same therapeutic level.

The ceramic capsules will be implanted in spots such as the fleshy underside of an arm. The porousness of the ceramic can be adjusted according to the dosage required, says Bajpai. The capsules can also be completely absorbed by the body without any side-effects. And, it can deliver two or three drugs at the same time at different rates.

Bajpai has so far used his method only in experiments on rats. He found the rodents did not develop any of the usual AZT side-effects, even when constant levels of the drug were maintained in their blood for 60 days. He now plans to launch large animal testing of the system before starting human trials.