| In late April, ViRexx Medical, for which
| |
| | immunological agents designed to induce
|
| Dr. Tyrrell serves as the Chief
| |
| | the production of antibodies. "We haven't
|
| Executive, received authorization from
| |
| | used the platform with an adjuvant to get
|
| Health Canada, the country's regulatory
| |
| | an even stronger response," explained
|
| arm which is similar in nature to the
| |
| | Tyrrell. For example, nucleotidesis, the
|
| U.S. Food and Drug Administration, to
| |
| | short nucleotide sequences which are rich
|
| undertake a Phase I clinical trial for
| |
| | in CpG, or growth factors, such as
|
| its lead Chimigen⢠platform vaccine
| |
| | cytokines, can enhance the immune
|
| candidate, HepaVaxx B. Dr. Tyrrell hopes
| |
| | response.
|
| it might become a potential treatment for
| |
| | DEVELOPING A CLASS OF FLEXIBLE VACCINES?
|
| chronic carriers of the hepatitis B
| |
| | Ever the optimist, Tyrrell outlined his
|
| virus. Tyrrell told StockInterview, "The
| |
| | strategy, "Our plan is to go with one or
|
| platform is designed to try to get both a
| |
| | two antigens first and see that we get
|
| T and B cell response. Most conventional
| |
| | the appropriate immune response. If we
|
| vaccines induce just a B cell response."
| |
| | do, then we will be looking at other
|
| STIMULATING BOTH ARMS OF THE IMMUNE
| |
| | antigens, not only from viruses, but we
|
| SYSTEM
| |
| | can be looking at cancer antigens in this
|
| It is the dendritic cells, which
| |
| | platform." Dr. George echoed Tyrrell's
|
| stimulate the B-Lymphocytes and produce
| |
| | sentiment, "We should be able to use this
|
| antibodies. For example, the mumps
| |
| | platform for cancer therapy, depending
|
| vaccine was designed to give a B cell
| |
| | upon the cancer antigen we use. We can
|
| response, providing someone with good
| |
| | plug in a specific cancer antigen into
|
| protection for a number of years. As Dr.
| |
| | this platform, and the vaccine targeted
|
| Rajan George had told us, "The B-Cells
| |
| | to dendritic cells." The company has also
|
| produce antibodies against the virus
| |
| | been evaluating some bioterrorist viruses
|
| antigen, which we have put in the
| |
| | in conjunction with an arm of Canada's
|
| Chimigen⢠vaccine. The antibodies
| |
| | Defense Department. Dr. George also
|
| are specific to the antigen and bind to
| |
| | pointed out, "Our chimigen technology is
|
| the viruses because they have the
| |
| | not found anywhere outside of our
|
| antigen. The system removes the virus by
| |
| | laboratories. This approach has not been
|
| binding with the antibody." The platform
| |
| | tried before for chronic HBV or HCV
|
| is also expected to remove the infected
| |
| | infections." Because the scientists
|
| cells using cytotoxic T-lymphocytes.
| |
| | believe the Chimigen⢠platform is
|
| The big breakthrough in treating many
| |
| | one which may be flexible and adaptable
|
| infectious, and other, diseases would
| |
| | for the treatment of both infectious
|
| come with the vaccine platform capable of
| |
| | viruses and cancers, a new class of
|
| stimulating both a T and B cell response.
| |
| | vaccines may be developed over the coming
|
| "It would be a major step forward,"
| |
| | decade.
|
| Tyrrell noted, "if we could find a way to
| |
| | While awaiting the results of the initial
|
| increase the efficiency of some of these
| |
| | human clinical trials, Dr. Tyrrell did
|
| therapeutic vaccines." ViRexx Medical's
| |
| | reach a very definite conclusion about
|
| infectious disease department conducted a
| |
| | the mission in his journey, "Unless you
|
| number of ex vivo laboratory experiments
| |
| | have both arms of the immune system, you
|
| to evaluate the immune responses the
| |
| | may not have lifelong immunity."
|
| Chimigen⢠platform might produce.
| |
| | Tyrrell's down-to-earth thinking may have
|
| "We showed what we had predicted in
| |
| | come from being born on a farm in rural
|
| theory has been true," Dr. George told
| |
| | Alberta, west of Edmonton, the big city
|
| us. "We have also done some animal
| |
| | where his college alma mater can be
|
| experiments, where the vaccine showed
| |
| | found. At one time, he had considered
|
| similar effects, again, as predicted. For
| |
| | becoming a rural family physician or a
|
| HepaVaxx B, the animal results are also
| |
| | veterinarian. His erstwhile aspiration to
|
| showing great progress and promise."
| |
| | work with animals is ironic, because his
|
| Tyrrell is more reserved in his
| |
| | research has involved virally infected
|
| expectations, "Let's see how the platform
| |
| | duck models, chimps who love the taste of
|
| works when tested in humans. If this can
| |
| | TangÂ(R), and mouse antibodies. But
|
| be used to stimulate both a T and B cell
| |
| | Tyrrell's curiosity to solve complex
|
| response, then it would be a significant
| |
| | scientific riddles has taken him beyond
|
| breakthrough."
| |
| | those once-simple goals.
|
| There could be stumbling blocks ahead. A
| |
| | His competitive drive for milestones was
|
| chronic hepatitis B carrier is exposed to
| |
| | first evidenced by winning a gold medal
|
| a number of antigens in his or her body.
| |
| | in science, while an undergraduate
|
| Tyrrell has further concerns which may
| |
| | majoring in chemistry at the University
|
| arise. Perhaps the antigen might not
| |
| | of Alberta. An then, with an award of a
|
| trigger a strong enough response. Or
| |
| | New York Life insurance scholarship,
|
| something may be discovered during the
| |
| | during his second year in medical school,
|
| Phase I trials, such as "Are there
| |
| | for a combined MD/PhD. Only twenty-two
|
| regulatory T cells, or cells that are
| |
| | medical students in North American won
|
| being paralyzed and not being allowed to
| |
| | such a scholarship that year. Or perhaps
|
| stimulate a strong immune response in
| |
| | he hoped where his journey might someday
|
| these patients? That is why one tests in
| |
| | take him, when he won an MRC Centennial
|
| humans after successful animal tests, to
| |
| | fellowship to study virology, for two
|
| address those points of interest. As Dr.
| |
| | years, at the Karolinska Institute in
|
| George reminded us, "Until then, our
| |
| | Stockholm. For those unfamiliar with this
|
| optimism is based on laboratory results."
| |
| | Swedish institute, it is the home of the
|
| Tyrrell has already begun thinking a few
| |
| | Nobel Prize. Is this where Dr. Lorne
|
| steps into the future, "I really believe
| |
| | Tyrrell's journey might one day reach its
|
| we've found a way of directing the right
| |
| | final destination? The answer to this
|
| immune response chimigens, but we may
| |
| | question may come from the results of the
|
| have to use adjuvants to get a strong
| |
| | clinical trials for his Chimigenâ¢
|
| immune response." Adjuvants are
| |
| | platform.
|
