Strong Immune Response Rates Seen in Inovio's HIV Vaccine

New preliminary results suggest promise for a potent vaccine against HIV.

Inovio Pharmaceuticals announced its HIV vaccine candidate PENNVAX-GP produced the highest overall levels of immune response rates ever seen in a human study for this type of treatment.

The trial is supported by the HIV Vaccines Trial Network (HVTN) and the National Institute of Allergy and Infectious Diseases (NIAID).

The study’s goal was to evaluate a four-dose regimen of PENNVAX-GP DNA vaccine in conjunction with an immune activator called IL-12. Investigators delivered the treatment via intradermal or intramuscular administration to 85 patients. Nine patients received a placebo as a control.

Essentially, the treatment regimen elicited a T-cell immune response in 93 percent of vaccinated subjects whereas 94 percent of subjects produced an antibody response.

By contrast, none of the patients demonstrated a cellular or antibody response in the placebo group.

Another interesting finding is that similar immune responses and response rates were achieved through both administrations of the vaccine, but subjects who received the intradermal method got one-fifth the dose of the vaccine compared to the intramuscular administration.

“These results are among the highest ever responses we’ve seen with an HIV vaccine, and they are remarkably consistent with our recent data reported from our Ebola, Zika and MERS clinical trials in terms of demonstrating nearly 100% vaccine response rates with very favorable safety profile. Furthermore, our newer and more tolerable intradermal vaccine delivery device showed that we can elicit very high immune responses at a much lower dose,” said Inovio’s President and CEO Dr. J. Joseph Kim, in a statement.

PENNVAX-GP is comprised of four HIV antigens engineered to cover multiple global HIV strains in order to generate an antibody and T-cell immune response to simultaneously prevent and treat the pathogen.

Next, investigators will continue to assess the vaccine’s safety and efficacy profile. The company is also exploring a potential combination with Pennvax-GP and checkpoint inhibitor, reported FierceBiotech.

The project with Inovio has been funded through a $25 million contract previously awarded in Inovio and its partners in 2009.

Stephen De Rosa, the protocol co-chair of the study, presented these early-stage results at the 2017 HVTN Spring Full Group Meeting.