Snail venom painkiller launched

Snail venom painkiller launched

A drug that harnesses the power of deadly sea snail venom has been launched in Britain.

Prialt is a strong painkiller designed for patients suffering from chronic pain who cannot tolerate treatments like morphine. It is based on a toxin produced by a the magician's cone snail. Cone snails "harpoon" passing prey

The snail uses venom to paralyze passing fish, but scientists found chemicals in the poison could also block pain signals in the human brain. Conus magus, or the magician's cone snail, is one of about 500 species of cone snail. It is found in tropical waters such as the Great Barrier Reef and in the South Pacific.

These snails are nature's pharmaceutical drug designers Dr Jon-Paul Bingham

It hunts by harpooning its prey and injecting it with venom before swallowing now-immobile fish whole.

About 25 years ago, scientists at the University of Utah, in the US, managed to isolate a molecule from the venom that also had painkilling properties in humans. The molecule works by preventing nerve cells from sending pain signals to the brain.

Now researchers have created a synthetic version of the compound with similar pain-killing effects, and it forms the basis of this new drug, Prialt. Prialt is injected directly into the fluid surrounding the spinal cord through a small pump worn by the patient. It is to be used for those suffering extreme chronic pain - such as cancer patients - for whom morphine is ineffective or unsuitable. Many scientists think cone snails may yield more medicines - and teams are looking at the venoms in different species to see if they can isolate compounds to treat diseases including Alzheimer's disease, Parkinson's disease and epilepsy.

Prialt molecule blocks calcium channels in specific nerve cells, preventing certain pain signals from reaching the brain. It targets a particular subgroup known as N-type calcium channels, which play a role in some kinds of pain. Prialt requires that a pump be implanted or used externally to send the drug by catheter into the spinal fluid, a technology often reserved to deliver morphine to critically ill AIDS cancer patients. Prialt is designed to ease persistent pains in people who suffer from various types of cancer and other very serious diseases. It is a very powerful drug, as it was created to lessen chronic pains in individuals that no longer responded to morphine therapy.

http://www.physorg.com/news82662614.html
http://news.bbc.co.uk/2/hi/health/5165124.stm
http://query.nytimes.com/gst/fullpage.html?res=990DE2DE1F3FF935A3575BC0A960958260&sec=health&spon=&pagewanted=all