LICR Targeted Therapies
Cancer Vaccines
Several cancer vaccines are in late stage clinical
development, but very few have thus far been approved for marketing worldwide.
The currently approved vaccines are comprised of tumor cell-derived components
that contain uncharacterized mixtures of potentially immunogenic and immunosuppressive
components.
Approach
The LICR believes that future efforts to improve upon the partial clinical
success of the commercially available vaccines may be compromised by a
limited understanding of the critical components that may activate an
immune response against cancer. LICR has therefore chosen to pursue a
comprehensive strategy for the development of cancer vaccines, based upon
the identification of the antigens most effective for inducing immunity
against cancer.
To develop cancer vaccines, LICR and the Cancer Research Institute (CRI)
in New York, USA have established the Cancer
Vaccine Collaborative, an innovative partnership between two not-for-profit
groups that are committed to taking responsibility for translating their
laboratory discoveries into effective cancer therapies.
Cancer vaccines are developed through several steps:
- Identification
of Cancer Antigens: The use of methods pioneered by LICR
investigators to identify cancer antigens based upon their inherent
immunogenicity; i.e. interaction with humoral (antibody) and cellular
(T cell) components of the immune system (see Cancer
Antigen Discovery Program).
- Characterization
of Antigens: Exhaustive mRNA and immunohistochemical characterization
in vitro are undertaken to determine cancer restricted
expression and definition of the fine specificity of serological
and T cell reactivity (see Cancer
Antigen Discovery Program).
- Comparison of
Vaccine Reagents and Adjuvants: A meaningful evaluation
of four broad antigen compositions - protein, peptide, live vectors,
and plasmid DNA - is only possible in a human setting. Thus, antigenic
compositions are being tested in multiple parallel trials at several
clinical sites, each testing a single variable to evaluate safety
and induction of specific immunity. Due to heterogeneity of antigen
expression and the possibility of immune evasion or escape by tumors,
LICR continues to evaluate additional components for use in combination
with defined vaccines and multiple-antigen vaccines (see Cancer
Vaccine Program).
- Evaluation of
Immune Response: The measurement of humoral and cellular
immune responses using standardized monitoring methodologies, enables
data from different clinical trials to be compared meaningfully.
Additionally, the meticulous immunological monitoring of immunized
patients in early-phase clinical trials is a key element for developing
successful vaccines (see Cancer
Vaccine Program).