14 March 2013 -- Scancell Holdings Plc, (AIM:SCLP), the developer of therapeutic cancer vaccines, would like to alert
shareholders to the recent article “IgG4 subclass antibodies impair antitumor immunity in melanoma” in the
peer reviewed cancer journal: The Journal of Clinical Investigation, published on 1 March 2013.
The new study published in The Journal of Clinical Investigation supports earlier studies by King’s College
London that indicate that patients with the cancer, malignant melanoma, appear to elicit a weak antibody
response to the tumour cells which appears to be relatively ineffective in combating the cancer and which
may in effect switch off the immune system.
This study indicates that patients with malignant melanoma initiate a B cell immune response to produce an
antibody called IgG4. IgG4 is considered a “weak” subclass of antibody and is thought to inhibit the
production of other stronger antibodies such as IgG1, actually protecting the tumour cells from a more
effective and aggressive attack from the patients’ immune system.
Scancell’s melanoma cancer vaccine SCIB1, which is currently in Part 2 of a Phase I/II clinical trial, works by
activating the immune system through T cells rather than B cells. The Board believes that T cell activation is
a more effective approach to treating patients with an immune system compromised in the manner found in
those with malignant melanoma.
Dr Richard Goodfellow, joint Chief Executive Officer of Scancell, comments: “We believe that The Journal of
Clinical Investigation paper supports Scancell’s approach to fighting cancers, such as malignant melanoma,
where T cell activation appears to be the more effective route of combating this often fatal disease. Results
from our Phase I/II clinical trial are expected at the end of this year.”
For Further Information:
Dr Richard Goodfellow, Joint CEO
Professor Lindy Durrant, Joint CEO
Simon Conway/Mo Noonan
Annie Cheng, CFA
Camilla Hume/Stephen Keys
Scancell Holdings Plc + 44 (0) 74 2323 0497
FTI Consulting +44 (0) 20 7831 3113
Visible Value LLP + 44 (0) 74 2323 0497
Cenkos Securities plc + 44 (0) 20 7397 8900
Scancell is developing therapeutic vaccines for the treatment of cancer and infectious diseases based on its
ImmunoBody® and Moditope™ technology platforms. Scancell’s first cancer vaccine SCIB1 is being
developed for the treatment of melanoma and is in Phase 1/2 clinical trials. Preliminary evidence from Part 1
of the study showing that SCIB1 produced an immune response which might be associated with clinical
benefit in patients with malignant melanoma was released in December 2012.
Treating cancer by vaccination allows small non-toxic doses of a vaccine to be administered to a patient,
stimulating an immune response. Effective cancer vaccines need to target dendritic cells to stimulate both
parts of the cellular immune system; the helper cell system where inflammation is stimulated at the tumour
site; and the cytotoxic T-lymphocyte or CTL response where immune system cells are primed to recognise
and kill specific cells.
A limitation of many cancer vaccines currently in development is that they cannot specifically target dendritic
cells in vivo. Several groups have demonstrated successful vaccination by growing dendritic cells ex vivo,
pulsing them with tumour antigens and re-infusing them. However, this procedure is patient specific, time
consuming and expensive. Scancell has developed its breakthrough patent protected ImmunoBody®
technology to overcome these limitations.
Scancell has also identified and patented a series of modified epitopes that stimulate the production of killer
CD4 that destroy tumours without toxicity. The Directors believe that the Moditope™ platform could have a
profound effect on the way that cancer vaccines are developed.