Cell to cell communication is a cornerstone of maintaining
homeostatic health in any multicellular system. There are libraries of
research on the exchange of information amongst human cells, such as
peptides, chemokines, growth factors and lipids, just to name a few.
Comparatively speaking, it has only been in recent years that there is a
growing body of evidence regarding the importance of exosomes,
specialized nanometer-sized vesicles, in the cellular matrix of the
human body. Although they can be derived from different types of cells,
promising research is emerging that validates exosomes to be important
new therapeutic targets in cancer care.
At present, small molecule therapies are the most widely used
approach in cancer treatments. In many cases they are rendered
ineffective due to resistance or to debilitating side effects, leaving
the oncology landscape extremely challenged to develop new, innovative
approaches. Immunotherapy, which uses the body's immune system to fight
tumors, has delivered some very promising advanced data in the last
decade, with Dendreon Corporation (DNDN) becoming the first
immunotherapy to garner FDA approval in April 2010 as a new treatment
for certain men with advanced prostate cancer.
The attractiveness of immunological cancer drugs was exemplified on August 26 when AstraZeneca (AZN) agreed to pay
up to $500 million to acquire privately-held Amplimmune, to get its
hands on several early-stage novel therapeutics focused on
immune-mediated cancer therapies. The deal entails AstraZeneca paying
$225 million upfront with promises of up to $275 million more should
certain developmental milestones be met.
Perhaps what best demonstrates the value of a potential new
immunological cancer therapy is the fact that Amplimmune's most advanced
drug candidate, AMP-514, is still only in the pre-clinical stage with
intentions to file an Investigational New Drug application with the FDA
by the end of 2013.
The growing efforts of big pharma to find ways to allow the immune
system to combat tumors should lend optimism to the millions of cancer
sufferers globally and inspire investors to take notice of a burgeoning
field in cancer research. How big is the market becoming? According to
Research and Markets recent update, there are now 571 companies and partners developing 1,007 immunotherapy candidates across 2,500 different cancer projects.
The fact remains that cancer is a resilient creature that is capable
of mutating and developing harsh resistance to cancer therapies.
Exosomes have recently been discovered to play multiple roles in muting
the effect of cancer therapies, including the programmed cell death of
cancer fighting immune cells and the facilitation of drug resistance,
which could prove a challenge for any or all of those 1,007
immunotherapy candidates. Further evidence shows that exosome creation
can be accelerated in hypoxic conditions, a condition that is supportive
of tumor progression, metastasis and angiogenesis.
The point is that the benefit of cancer immunotherapies designed to
stimulate the immune response may very well require a synergistic
adjunct mechanism to eliminate exosome immune-suppression.
Few companies are targeting the eradication of exosomes like Aethlon
Medical Inc. (AEMD). Aethlon's primary asset is its ADAP(TM) System that
functions as a pillar for a new class of medical devices that deliver
rapid removal of infectious viruses, toxins and disease promoting
particles, including exosomes, from the circulatory system. The
company's Hemopurifier® has been validated in overseas clinical trials
to substantially reduce viral loads in diseases such as hepatitis C. In October of 2012, the company was granted a U.S. patent
that provides Aethlon Medical the exclusive right to remove immune
suppressive microvesicular particles, which include but are not limited
to exosomes, from the circulation of treated patients. Aethlon recently
received an FDA Investigational Device Exemption that allows the company
to conduct Hemopurifier clinical trials in the U.S. in end stage renal
disease patients with hepatitis C. While that alone should be a
catalytic moment for the company, researchers have also discovered that
the same Hemopurifier being advanced into hepatitis C studies can
capture the exosomes underlying several forms of cancer.
The company has garnered awareness of its technology as related to
hepatitis C and its U.S. military contract for the treatment of sepsis,
with shares more than doubling in value in 2013, but there seems to be a
strong underlying value that has not yet been realized relating to
cancer. With this disease, Aethlon's goal is to improve drug treatment
outcomes through an adjunct strategy that can remove cancer-released
exosomes without added drug toxicity normally required to expand a
cancer treatment regimen.
As mentioned, exosomes are immunosuppressive by nature, meaning that
the efficacy could be elevated in the droves of immunology cancer drugs
and drug candidates in development. This positions the Hemopurifier as a
true adjunct, which might also be attractive to developers of drug
candidates that are not demonstrating sufficient efficacy to warrant
market approval. Extracorporeal treatment could be the solution. Of
course, a combination therapy with traditional chemotherapies is a
possibility as well.
As the first device of its kind and a microcosm of the total oncology
ecosystem, the Hemopurifier and Aethlon are fighting through headwinds
for acceptance. However, the government has taken notice, investors are
taking notice and domestic clinical trials for such a prominent disease
as hepatitis C should continue to build awareness of the potential of
products that emanate from the Aethlon ADAPT pipeline. With some more
research quantifying the benefits of removing circulating exosomes, the
technology could experience market acceptance in cancer and other
indications where exosomes have been discovered to enable disease
progression through suppression of the immune system.