A Coleraine company, Gendel, has developed a remarkable drug-delivery system that uses red blood cells and ordinary diagnostic ultrasound that can deliver pharmaceuticals to the specific organ or location where they are needed. The firm hopes to tap into the rapidly growing market for unique delivery systems that can make drugs more effective.

"The key issue here really is targeting," explained Mr Alan Patterson of Gendel. "Basically, the key advantage of the system over anything else is the system allows us to release the medicines at a target organ or a target site in the body."

The company is based at the Coleraine campus of the University of Ulster and will shortly be moving into the new Science Research Park there. It was founded late in 1998 by three people: Dr Tony McHale, senior lecturer in the university's Department of Biomedical Science who invented the technology; Dr Roger Craig who is a scientist and entrepreneur; and Northern businessman, Mr Patterson.

The company announced the involvement last March of venture capital company 3i. It has also received backing from the Industrial Research and Technology Unit of Northern Ireland and from private investors. First-year funding of £900,000 (#1.14 million) was raised and the company is currently involved in a second round of interim funding.

It has 12 full-time staff, many of them post doctoral researchers, but Mr Patterson said the firm was about to seek additional staff. He expects there to be 40 employees within two years.

Gendel, he said, hoped to benefit from the rapid growth of the drug-delivery sector rather than general biotechnology or drug development. Drug-delivery companies were growing at an average 15 per cent per annum, he said, compared to general pharmaceuticals which were growing by about 6 per cent per annum.

Putting drugs into red blood cells is not a new technology, Mr Patterson said and had been done for 20 years. "What nobody was able to do was how to get the medicine back out of the red cells."

Dr McHale's achievement was to find a way to sensitise red cells to low-energy ultrasound waves. "Ultrasound is a safe and effective treatment" that uses sound waves to image tissues and is regularly used to assess foetal development in the womb, Mr Patterson explained.

"A red blood cell is basically a big volume carrier." It has no nucleus and there is plenty of room to insert soluble pharmaceuticals. "We have been able, without chemicals, to take that blood cell and make it sensitive to ultrasound."

Either the patient's own cells or cells provided by donors can be used. Pharmaceuticals are transported inside the cell membrane and the cell is treated to make it respond to ultrasound. The treated cells are then injected into the patient and will disperse throughout the circulatory system.

The ultrasound is positioned to target a particular organ, tumour site or other location in the body. When treated cells reach this location the ultrasound causes them to burst open, releasing the drug right where it is wanted. The cells' large carrying capacity means that very few cells are needed, only a few millilitres, and the lost cells do not cause any inflammatory response. In any case, ageing cells die in the body all the time, Mr Patterson pointed out and caused no difficulty for the body's waste disposal processes.

The technique provided a high level of control over the release of the drug, he said, unlike conventional tablet or injection delivery which is based on having a drug present throughout the circulatory system. This can be an important consideration when using chemotherapy for example which employs highly toxic substances that can affect all tissues.

The technique is also particularly applicable to the new generation of protein and DNA-based medicines, pharmaceuticals with potential sales of $20 billion (#20.8 billion) worldwide, Mr Patterson said.

These drugs are made from quite large molecules, and suffer from being less bio-available when taken orally. They are easily transported inside the red blood cell, however, and can then be released where they are needed.

"We are targeting conditions such as oncology, coronary and vascular diseases," he said. The technique also holds promise to assist "angiogenisis", the process whereby the body grows new blood vessels.

No human trials are under way, but the technique has been fully tested using other models, he said. The additional staff will help the company move towards full clinical trials in humans, initially using a well defined group of drugs after clearance by the regulatory authorities.

The technique opens up potential for linkages with pharmaceutical and biotech companies, he suggested. "The company will be going into partnerships with other drug and biotech companies. We can solve problems for them and add value to their products."