ImmunoVaccine Technologies DepoVax Shows Positive Results for Cancer and Infectious Diseases

06-Oct-2008 - Canada

ImmunoVaccine Technologies (IVT) patented depot vaccine formulation, DepoVax(TM) is showing positive pre-clinical results, with single-dose efficacy achieved in therapeutic cancer and several infectious disease vaccine models. The results of this research will be presented at the Ehrlich II conference in Germany. Collaborators from the University of Miami will also be reporting on the capabilities of IVT's depot formulations for delivery of DNA and SiRNA in vivo.

DepoVax(TM) provides a unique single-dose capability, and is based on a novel approach to the use of liposomes, which encapsulate a target antigen and adjuvant. The vaccine formulation also relies on a hydrophobic oil carrier. The result is a depot effect that significantly enhances vaccine induced cell-mediated and humoral immunity.

The efficacy of a single dose of a DepoVax(TM) formulation was shown using a Human Papilloma Virus (HPV) associated cervical cancer model. In the therapeutic C3 tumor challenge model, DepoVax(TM) eliminated 100% of established cancerous tumors after a single dose. In contrast, tumors remained intact when treated with a placebo vaccine. The effect of the vaccine is linked to the activation of a potent and specific cellular immune response.

"We have developed depot vaccine formulations that can induce a more effective immune response than other vaccination strategies used in the clinic today," said Dr.Marc Mansour, vice president of R&D at IVT. "We look forward to testing our therapeutic cancer formulations in the clinic this coming year."

For the humoral response, a recombinant H5 antigen was used. IVT immunized models once with the DepoVax(TM) vaccine formulation, and once or twice with a control alum-based vaccine for avian influenza. At all time points tested, as early as 18 days and for at least 20 weeks, antibody titers induced by the depot vaccine were 10-15 times higher than a single dose of the control alum vaccine. The vaccine induced quick and strong specific immunity against the avian influenza antigen. In the longer term, the antibody responses generated were superior or equal to the two-dose alum vaccine.

"Typically, vaccines need booster shots to be effective, which is not an option in a pandemic situation," said Mansour. "Our depot vaccine formulation makes a single-dose pandemic flu vaccine a strong possibility."

IVT's strategy is multi-targeted; the company is exploring pandemic and seasonal influenza, as well as Hepatitis B. In addition, IVT is designing HLA-A2 peptide-based therapeutic depot vaccines for breast, ovarian and prostate cancers. By using tumor-specific peptides, IVT's depot vaccines induce a potent cellular response that destroys 100% of the tumors, indicating a promising immunotherapy for cancer.

https://www.bionity.com/en/news/87767/immunovaccine-technologies-depovax-shows-positive-results-for-cancer-and-infectious-diseases.html