Researchers at Dalhousie University in Halifax, Nova Scotia, founded Immunovaccine about 10 years ago. The Canadian government asked them to create a contraceptive vaccine to humanely control seal populations. The resulting vaccine technology was successful not only in seals but also worked on other wild animals including monkeys in Hong Kong.
The scientific challenge for inoculating wild animals was to design a vaccine that needs only a single injection and lasts a decade. "The delivery system was the secret," says Immunovaccine’s president and CEO, Randal Chase, Ph.D.
Now researchers at Immunovaccine in Halifax are applying the same delivery system to human vaccines aimed at cancer and infectious diseases. "There are no human vaccines where a single injection lasts 10 years," notes Dr. Chase.
The company’s DepoVax™ platform consists of vaccine antigens and adjuvants wrapped in liposomes within an oil depot. Liposomes allow more antigen and adjuvant to be injected compared to oil alone, and they hold the antigen and adjuvant together, resulting in a powerful and long-lasting immune response.
When injected, the combination forms a "depot vaccine" that remains active for weeks to months. A single dose generates strong cellular and humoral immune responses. "The delivery system is basically the same for therapeutic and preventive vaccines," Dr. Chase says.
The DepoVax platform reduces the standard two to three injections of a vaccine needed for optimal immunity to just one, and it gives an earlier onset of protection, according to Immunovaccine. The firm says that in preclinical models, a single dose prevented the growth of tumors and up to 100% of cancer cells were destroyed. DepoVax works with a variety of antigens including peptides, proteins, nucleic acids, and synthetic antigens. The dry formulation can be stored and reconstituted for clinical use.
Immunovaccine says its patent protection is broad and covers combinations of any antigen, any adjuvant, and any liposome mixed with any oil. "We have a rocket booster system that enhances the immune response," says Dr. Chase, and "we can boost the immune response of any vaccine."
To prove the advantages of their platform, researchers at Immunovaccine invite other vaccine companies to take the "DepoVax challenge". Companies send their vaccines to Immunovaccine, where they are reformulated free of charge with the liposome/oil delivery system and then returned to undergo head-to-head testing.
"We believe that we can deliver other people’s products better than they can," Dr. Chase says. He notes that for many vaccines, fewer doses are required, because the DepoVax system induces a much stronger immune response. He also adds that the DepoVax challenge has led to licensing agreements on a broad range of applications.