July 30, 2020 -- Inovio released results of a nonhuman primate study for its COVID-19 DNA vaccine, INO-4800. The vaccine protected the animals 13 weeks after vaccinations and mediated T- and B-cell immune responses, according to the firm.
The results, published on bioRxiv, demonstrated that INO-4800 reduced viral load in the lungs and nasal passages of macaques that received two doses of INO-4800 (one mg) four weeks apart followed by live virus challenge 13 weeks after the second dose.
The vaccinated macaques demonstrated seroconversion after a single dose, with neutralizing antibodies and T cells found in their blood more than four months after the initial dose. Moreover, the levels of antibodies were similar to or greater than those who have recovered from COVID-19. The study showed that the vaccine induced acute and memory T- and B-cell responses, including neutralizing antibodies against the early virus strain as well as the now dominant G614 variant.
The company anticipates beginning phase II/III efficacy trials this summer. A separate nonhuman primate study evaluating the durability of INO-4800 at 12 months postvaccination is currently underway and is supported by the federal government's Operation Warp Speed to accelerate development of a vaccine for SARS-CoV-2.