Meditech pursues psoriasis therapy

By Graeme O'Neill
Wednesday, 08 December, 2004

Melbourne biotech Meditech Research (ASX:MTR) has signed a collaborative research agreement with Griffith University's Institute for Glycomics to develop novel carbohydrate-based topical drugs for inflammatory skin diseases, including psoriasis.

Meditech and Glycomics Institute researchers are employing fragments of a ubiquitous molecule in the body, hyaluronic acid (HA), to ferry drug molecules through the skin, to defuse inflammatory reactions in situ.

Meditech Research director, Dr Tracey Brown, said the main focus of the project, which is supported by an AUD$240,000 Australian Research Council Linkage Grant is to develop new, more effective drugs for psoriasis, but new treatments eczema and other skin disorders may also be explored.

Brown said current psoriasis therapies, which include monoclonal antibodies, and potent immunosuppressants like methotrexate and cyclosporine, are administered systemically, and can cause long-term damage to the liver and kidneys.

In psoriasis, inflammatory immune-system cells and keratinocytes, over-express CD44 receptors, one of the major ligands for hyaluronic acid (HA), a complex polysaccharide found throughout the human body.

Dr Jennifer Wilson's research team at the Glycomics Institute has developed carbohydrate-based "scaffold" molecules that can link fragments of HA to commonly used psoriasis drugs.

The HA fragments will target the drugs directly to cells over-expressing CD44 receptors at the site of the lesion.

Brown said HA readily penetrates the skin, and she has already done experiments that show that direct, transdermal delivery drastically reduces the high, potentially toxic dosages required when the same drugs are delivered systemically.

If the project is successful, only tiny therapeutic doses will be required, minimising side effects and damage to non-target organs.

Wilson said the approach had not been attempted previously, and could result in significantly improvement treatment and a better quality of life for patients with the debilitating disease.