MVI is developing more vaccines for prostate cancer, in more stages of the disease, in combinations with more agents, in more clinical trials, involving more patients, with safety based on more doses administered, when compared to our nearest competitors.
MVI vaccines are designed to activate the body’s own immune system to kill prostate tumors, an outcome that may prevent or delay crippling bone metastases, and improve quality and duration of life.
Plasmid DNA vaccines have several advantages compared to protein or peptide vaccines: DNA can be rapidly and inexpensively purified, there are no problems with solubility, and DNA vaccines are relatively more stable in storage. MVI DNA vaccines induce exclusively antigen-specific CD4+/CD8+ T-cell responses; the type of immune response capable of destroying tumor cells.
MVI-816 (aka pTVG-HP) targets prostatic acid phosphatase (PAP), a well-defined and clinically validated prostate antigen suitable for prostate cancer therapeutic vaccines.
MVI-118 (aka pTVG-AR) is MVI's vaccine targeting the androgen receptor (AR) ligand binding domain. It is ideally suited for combination therapy with the new generation of androgen axis inhibitor drugs coming to the market to treat prostate cancers.
The critical assumptions underlying MVI technology are that immunization with plasmid DNA is a competent means to elicit Th1/CTL-biased immune responses in humans, and that vaccination will be most efficacious if used in the minimal residual disease setting, before overt metastases can be detected by standard imaging technologies. It is widely recognized that a productive immune response to a vaccine, or effective blockade of immune checkpoints, each may be insufficient modalities on their own to induce meaningful clinical responses. MVI's clinical trials are exploring combinations of these agents in various stages of prostate cancer.
The clinical rationale for MVI vaccines is that induction of a productive CTL response will result in significant delay in both progression to overt metastases and the initiation of castration therapies for men with non-metastatic prostate cancer, and prolonged duration of disease control in patients already receiving ADT and/or second generation AR inhibitors in the case of the AR vaccine. These preclinically validated combinations are now showing clinical activity in men with prostate cancer, and may significantly improve quality of life due to their strong safety and tolerability profiles.