Deadly fish's poison promising painkiller

By RACHELLE YOUNGLAI

A tiny company wants to use poison from a fish - a substance more toxic than cyanide - to help cancer patients suppress pain or to wean heroin addicts off their habit.

International Wex Technologies, a Vancouver-based company listed on the small-cap Canadian Venture Exchange, says early trials show positive results from tetrodotoxin, although bigger and more extensive tests will be needed before the product reaches the marketing stage.

It says the new drug could be on the market within three years.

The drug is derived from a blowfish poison - a substance so dangerous that a mere trace can paralyse a person within minutes.

The blowfish is known to gourmets as the source of the sometimes deadly Japanese fugu delicacy, a dish that can be prepared only by trained and licensed chefs, because the slip of a knife can poison the food, causing the diner to drop to the ground convulsing and gasping for air.

It has been called the culinary version of Russian roulette.

However, the drug derived from the poison, tetrodotoxin, has already passed two phases of clinical tests, and doctors conducting early surveys say it eased pain in terminally ill cancer patients, where no other pain medication had worked.

"It quickly became apparent that some patients were having a dramatic response," said Dr Edward Sellers, a professor of pharmacology at the University of Toronto who helped Wex conduct its Phase 2 trials.

Professor Sellers said one patient in his mid-50s was in such agony that he could not even wear his clothes without surges of pain.

With shots of Tectin, Wex's patented name for tetrodotoxin, his pain subsided for over a week.

Researchers injected patients with several micrograms of Tectin - a quantity so small it cannot be seen with the naked eye - twice a day for four days, and found that nearly 70 per cent experienced a reduction in pain.

Pain relief began around the third day of treatment, and often lasted after the final injection. In some cases, the relief extended beyond 15 days, the study showed.

Tectin, a sodium channel blocker, stops nerves from sending pain signals to the brain.

The company says Tectin differs from other painkillers in that it does not have the same side-effects as morphine and its derivatives, doesn't interact with other medicines and is not addictive. It is up to 3200 times stronger than morphine.

The success of the early Tectin tests is a small coup for a company that has set its sights on the US$38 billion ($58.71 billion) North American painkiller market.

Wex says that each blowfish can provide about 600 doses of the drug from within its liver, kidneys and reproductive organs, so there is no shortage of the toxin.

It was not always about pain for Wex. The company's founder, Hay Kong Shum, a medical technician who was educated in Russia and China, originally hoped Tectin would help ease withdrawal symptoms.

However, preliminary studies found the poison had painkilling properties. The company put the heroin therapy on the back burner and turned to the painkiller industry.

"It was the easiest way for us to get to market," said Donna Shum, Hay Kong's daughter and Wex's chief operating officer.

Wex's test results have caused murmurings among healthcare workers who wonder about the potential of this painkiller.

However, researchers and analysts are not yet touting Tectin as a drug to rival morphine. Wex still has to take its drug through crucial phase 3 trials, where it ramps up its test numbers to at least 400 patients.

The drug also faces an image problem. "Because it's associated with death, it got a bad rap," said Professor Sellers.

Although the scientific community may acknowledge the properties and benefits of the compound, it is less accepting of a drug derived from nature.

"There is a resistance from the medical community to accept treatments from the natural world," said Rob Peets, of Golden Capital Securities.

What is tectin?

* Tectin is a sodium channel blocker; it stops nerves sending pain signals to brain.

* Differences from other painkillers: does not have same side-effects as morphine and derivatives, does not interact with other medicines; not addictive.

* Up to 3200 times stronger than morphine.

- REUTERS