Fw: Snail venom/chronic pain/6/28/00

[Guest guest]

Thanks!!! All that information helps.

I sure hope something useful comes of it, and SOON!

I'm ready to be a guinea pig.

Kat

[Guest guest]

Snail venom/chronic pain

Introduction

A novel painkiller isolated from the venom of an

oceanic

snail may soon be approved for marketing to help the

hundreds of thousands of people with chronic pain

that does

not respond to conventional treatments. Called

ziconotide

(SNX-111), the drug is manufactured by Elan

Corporation,

plc, which received an approvable letter from the FDA

on

June 28, 2000.

Ziconotide is a manmade version of a substance

isolated

from the venom of cone snails -- carnivorous oceanic

snails

that sting their prey with a cocktail of

nerve-damaging

chemicals injected through a harpoon-like tube.

Ziconotide is

100 to 1,000 times more potent than morphine; indeed,

the

cone snail venom (conotoxin) is potent enough to

completely

paralyze a fish within a matter of seconds.

Scientists have

harnessed this creation of nature to produce a new

highly

targeted painkiller that blocks critical openings in

nerve cells,

interrupting pain signals on their journey through

the spinal

cord to the brain. Ziconotide is administered through

a small

tube directly into the spinal cord.

How Does It Work?

Pain signals depend on the transport of calcium

within cells.

Ziconotide blocks the pain-associated channels

through

which calcium ions travel without interfering with

channels

that convey normal sensations. As a result, pain is

relieved

without causing numbness.

Clinical Study Results

Elan reported that the basis of the FDA approvable

letter

were positive results from unpublished phase III

clinical trial

data on the use of ziconotide in more than 700

patients with

untreatable pain. The patients studied had either

failed

therapy with narcotics or could no longer tolerate

therapy

because of side effects. Significant pain relief was

achieved in

57% of these patients. (ref. 2)

Brose and colleagues (ref. 3) described the use of

ziconotide

in a 43-year-old man who had suffered from chronic

pain for

23 years after damage to the brachial plexus -- a

network of

nerves in the neck and shoulder. The patient reported

complete relief of his pain.

Adverse Events

Adverse side effects reported by patients receiving

ziconotide included dizziness, blurred vision, and

jittery eye

movement -- effects that could be resolved by

reducing the

dosage. Some patients experienced a slight reduction

in

blood pressure. Patients did not show signs of

tolerance or

addiction, even after many months of treatment.