Inovio Pharmaceuticals’ VGX-3100 therapeutic synthetic cancer vaccine has demonstrated that a DNA-based therapeutic vaccine can produce immune responses to kill target cells.

The clinical results indicate that its VGX-3100 therapeutic synthetic vaccine is capable of driving immune responses to antigens from high-risk types of human papilloma virus (HPV) infection and immune responses displayed a killing effect on cells changed by HPV into precancerous dysplasias.

Inovio president and CEO Dr. Joseph Kim said that the results indicate that a DNA-based immune therapy can generate potent and durable T-cell responses in people.

"Our ongoing phase II efficacy trial is designed to show that the immune responses seen in this study, in particular the generation of killer T-cell responses, may reverse cervical disease caused by chronic HPV infection," Dr. Kim added.

"The type of T-cell killing activity seen in this new data provides a growing foundation for efficacy trials focused on the treatment of HPV-associated cancers including cervical, head and neck, and anogenital cancers."

According to the phase I trial study data, 100% of patients (18 of 18) demonstrated antigen-specific antibody responses to Inovio’s vaccine, while 78% showed T-cell responses in the validated ELISpot assay.

T-cell immunity tests measured the ability of CD8+ T-cells from vaccinated patients to kill cells displaying HPV antigens on their surface, 91% of patients who developed T-cell responses showed the presence of CD8+ T-cells capable of this type of killing activity.

A current phase II trial is assessing the ability of its DNA-based VGX-3100 to treat cervical dysplasias caused by HPV infection.