Anavex Life Sciences Corp (AVXL)

[falconer66a]

It's the sigma-1 activation work-around.

I don’t understand how agonising S1R along with modulating M1/M4 can counter cell dysfunction ever present curtesy of a gene mutation. It may not be well understood at present, just intrigued to find out what might be going on.

Very, very good question. If there is some genetic anomaly that causes a disease (as in the case of Rett syndrome) how can the activation of the sigma-1 receptor protein actually fix things. Certainly, blarcamesine does not play with or correct actual genes. It does no genetic engineering. If a pathogenic (disease-causing) gene is present, it can operate, causing the disease.

But I'll use the case of my genetic condition, a mild form of hereditary spastic paraplegia (HSP). With this, as I've aged, my body produces ever smaller amounts of gamma-aminobutyric acid (GABA) in some of my nerves (mostly in my legs). Normal levels of GABA, in nerves, restrains their over activity, allowing normal brain control of muscles (among other things). I'm in my 70s, and for a dozen years the nerves controlling the adductor muscles in my legs have been hyperactive. Hence, my legs are stiff; I have to ambulate with a walker; can't negotiate staircases (fortunately can, however, safely control the brake pedal and throttle on my car — with an automatic transmission).

I took great delight in seeing the results of the first, tiny trial of blarcamesine in girls with Rett. Wonderfully, the drug markedly increased the girls' GABA levels. Previously, I saw (but unfortunately lost when I got a new computer) an obscure paper, as I recall, from France, where one of the Anavex sigma-1 receptor agonists (probably blarcamesine, with an earlier name designation) did the same thing in transgenic rats, with the genes for one of the forms of HSP. Like myself, these rats had poor control of their rear legs. The nerves controlling their adductor muscles were hyperactive, keeping the legs continually stiff. The rats got around by shuffling, dragging their rear legs. (Rats can't use a walker.)

Then, a sigma-1 receptor agonist (probably blarcamesine) was put in their drinking water. In a few days the HSP rats were gamboling around their cages normally, as though they had no HSP genes or symptoms.

Well, just as the case with the girls with Rett, the rats continued to have pathogenic genes; which when operating restricted normal production of GABA. Simply, blarcamesine allowed the neurons to make it. It's (one of many) homeostatic processes. The body needs some chemical to function properly. Cells detect this need (in the manner of a thermostat and room temperature) and "turn up" the production of the needed chemical. When there is a GABA deficiency, as in both Rett and HSP, the body detects this, but bad genes prevent the making of the essential chemical.

But, here's where blarcamesine does its work. It allows the homeostatic process to proceed, even in the presence of the bad gene. The bad gene restricts GABA production. But the cell, internally, signals a need for GABA. Blarcamesine does a biochemical work-around. It simply allows the cell to make the called-for GABA. Essentially, a) the bad gene is silenced, and b) normal production of GABA is otherwise facilitated.

It will be the same way with Alzheimer's, whether of geriatric or genetic origin. Alzheimer's sets in when neurons and nerves fail to chemically clear away normal waste proteins. With blarcamesine activation of sigma-1 receptors, the cell can once again make its called-for waste-clearing enzymes. They were lacking because they were being mis-folded; literally were bent of shape, so couldn't catalyze any targeted reactions. Blarcamesine facilitates proper protein folding; enzymes then work properly. Protein wastes in the neuron and nerves are then cleared. The nerves are still either aged or have pathogenic Alzheimer's genetics. But, by sigma-1 activation, blarcamesine has done an effective chemical work-around.