Scancell Holdings PLC. (SCNLF)

[Gift_Horse]

Moditope eradicates aggressive melanoma in transgenic mice

07 May 2014 | by mutatis mutandis

Moditope is a brand new immunotherapy. Scancell announcing its discovery in August 2012 explained that they had discovered a series of modified chemicals found only in cancer that stimulated the production of a very rare cancer killing immune cell called a killer CD4 T cell. Appearing infrequently and fleetingly in nature, Scancell was now able to utilize, and at the same time offer vaccine developers, a practical and convenient method to generate huge quantities of these rare cancer killing cells in cancer patients. Killer CD4 cells have a far greater potency than the killer CD8 cells that scientists currently stimulate in cancer patients with today's vaccines. Also because of their rarity cancer has been unable to evolve any means to protect itself against them.

Following their discovery the Scancell team followed a rigorous regime of testing to explore the efficacy of Moditope. First they tested to see if Moditope could generate an immune response in humans to show that its modified chemicals could cause the immune system to reject cancer. This was done by extracting blood cells from cancer patients and testing a Moditope vaccine on these cells which promptly produced large quantities of the human immune substances Gamma Interferon and Interleukin-17, showing a powerful immune response had taken place. The response was far more powerful than Scancell had seen before.

Then Scancell tested Moditope on humanized transgenic mice that had developed solid tumors. These mice were bred from the offspring of a female mouse that had received an implanted fertilized egg cell in her womb that incorporated a single human gene. This gene, called HLA-DR4, eliminated the possibility of differences in the way these mice presented Moditope to their immune systems. In other words vital elements of their immune systems were identical to those found in humans.

Scancell initiated tests by giving these 'humanized mice' a notoriously aggressive and difficult to treat form of melanoma called B16. Then after waiting 4, sometimes 7 and sometimes 10 days they selected those which had developed spreading tumors and immunized half with Moditope and left the remainder untreated. Astonishingly all tumors were eradicated completely in between 70 to 90 per cent of immunized mice. After 38 days all the untreated animals were dead but up to 85 per cent of those which had received the vaccine were still alive. The death of all the untreated mice is a testament of just how aggressive this particular tumor model is. In fact by day 14 the tumors of some of the untreated mice were so large the law required them to be culled for ethical reasons. So the up to 90 per cent eradication of all tumors in the immunized mice and an average of 85 percent overall survival was truly amazing, prompting Professor Durrant, Scancell's CEO, to comment: "I have never seen anything quite so profound as this in this aggressive tumor model."

As a special note, in a separate experiment which tested Moditope at the very limits of what is legally acceptable some of these mice only received the vaccine on day 14. Bearing in mind that a tumor response takes 7 days, that is it won't start working until day 21, 40 per cent of these late treated mice still saw a total eradication of their horrendously large tumors. Of course with human patients it would be very rare indeed to be treated at such an unacceptably late stage. Nevertheless this additional data is an important indication of the sheer power of Scancell's discovery.

The company maintains that Moditope can produce vaccines to treat all types of cancer. Indeed Scancell has recently employed more scientists with the intention of generating more Moditope vaccines. The object being to seek licensing partners and thereby generate revenue for the company going forward. Meanwhile Scancell is pressing ahead with their first in-house Moditope vaccine to treat triple-negative breast, cervical and womb cancer which is expected to enter human trials in early 2016.


Euro Investor